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Surgical resection of nonmelanoma skin cancer (NMSC) may be performed via Mohs micrographic surgery (MMS) or standard surgical excision with complete margin analysis. Whereas MMS may necessitate delayed reconstruction surgery, intraoperative frozen section analysis (IFSA) may be used to ensure clear surgical margins before proceeding with reconstruction. To achieve curative resection while optimizing aesthetic outcomes, surgeons may use surgical excision guided by IFSA to forego extensive or delayed reconstruction. Patients undergoing wide local excision for NMSC using IFSA from October 2008 to November 2016 were evaluated. Analysis included IFSA versus permanent section outcomes, the number of required excisions, and the recurrence rate. Our analysis contained 145 patients involving 162 lesions. IFSA demonstrated that 73.4 per cent of margins were negative after one excision and 26.5 per cent were re-excised until achieving negative margins. Analysis revealed one false-positive case (0.62%) and four false-negative cases (2.47%). Nine patients had local recurrence (5.56%). Frozen section sensitivity was 88.99 per cent and specificity 99.20 per cent. The positive predictive value was 96.97 per cent, and negative predictive value was 96.90 per cent. Mean follow-up time was 39 months. Both resection and recurrence data of excised NMSC lesions at our institution suggest that surgical excision using IFSA is a safe and effective alternative to MMS.

Background: In basic research, especially animal experiments, tissue histology with preserved organ morphology is essential, and the reliability of experiments depends on the quality of tissue sections. Frozen sections adequately maintain the antigenicity of tissues and are suitable for immunohistochemistry. However, thin frozen sections are often difficult to prepare from specimens. Therefore, a simple and fast method with a high success rate of specimen preparation is desired., New Method: In this study, we propose the "Sticker method," for preparing frozen sections using adhesive film, which is easy and maintains the whole organ morphology even in frozen section., Results: This method requires a simple adhesive film, and other components of general tissue fixation method with embedding medium. The present sticker method showed a higher success rate than the conventional method in preparing frozen sections., Comparison With Existing Method: Fragile frozen sections can be prepared with intact whole organ morphology without wrinkles. The advantage of the present method is that tissues can be embedded using only a common embedding medium and besides the adhesive film, no other special equipment is required. Furthermore, this method can be easily used by virtually every lab performing cryosections., Conclusions: The sticker method using adhesive films is characterized by a shortened preparation time and increased success rate of frozen section compared with conventional method., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Cryo-focused ion beam (FIB)-milling of biological samples can be used to generate thin electron-transparent slices from cells grown or deposited on EM grids. These so called cryo-lamellae allow high-resolution structural studies of the natural cellular environment by in situ cryo-electron tomography. However, the cryo-lamella workflow is a low-throughput technique and can easily be hindered by technical issues like the bending of the lamellae during the final cryo-FIB-milling steps. The severity of lamella bending seems to correlate with crinkling of the EM grid support film at cryogenic temperatures, which could generate tensions that may be transferred onto the thin lamella, leading to its bending and breakage. To protect the lamellae from such forces, we milled "micro-expansion joints" alongside the lamellae, creating gaps in the support that can act as physical buffers to safely absorb material motion. We demonstrate that the presence of micro-expansion joints drastically decreases bending of lamellae milled from eukaryotic cells grown and frozen on EM grids. Furthermore, we show that this adaptation does not create additional instabilities that could impede subsequent parts of the cryo-lamella workflow, as we obtained high-quality Volta phase plate tomograms revealing macromolecules in their natural structural context. The minimal additional effort required to implement micro-expansion joints in the cryo-FIB-milling workflow makes them a straightforward solution against cryo-lamella bending to increase the throughput of in situ structural biology studies., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The aim of this study was to assess the agreement rate between intraoperative evaluation (IOE) and final diagnosis (FD) in a series of surgically resected endometrial carcinoma (EC), with a preoperative ambiguous or inconclusive diagnosis by endometrial biopsies and imaging., Methods: A retrospective study was performed selecting patients who underwent surgery with IOE for suspected EC at our institution from 2012 to 2018. A K coefficient was determined with respect to the histotype, tumor grade, myometrial infiltration and cervical involvement., Results: Data analysis has been performed on 202 women. The IOE evaluation was distributed as Endometrioid (n = 180) and Non-Endometrioid (n = 22). The comparison between the frozen section (FS) and the definitive histological subtype showed an overall agreement rate of 93,07% (k = 0.612) and an agreement of 97.2% for Endometrioid vs 59% for Non-Endometrioid tumors. The FIGO system grading was the same in 91,1% of patients, none was upgraded and in 8,9% downgraded. Observed agreements were 89,11% and 95,54% for myometrial and cervical involvement, respectively., Conclusions: The good agreement between intraoperative grading, myometrial invasion and their histological definition on permanent sections highlights that FS is a good predictor for surgical outcome, in particular in presence of a preoperative ambiguous or inconclusive diagnostic evaluation.

Objective: To determine the accuracy of frozen section diagnosis and factors associated with final pathological diagnosis upgrade in patients with mucinous ovarian tumors., Methods: This study included 1,032 patients with mucinous ovarian tumors who underwent frozen section diagnosis during surgery. Sensitivity, specificity, and diagnostic accuracy of frozen section diagnosis was calculated. Univariate and multivariate regression analyses were performed to determine factors associated with diagnosis upgrade in the final pathology report., Results: The sensitivity and specificity of frozen section diagnosis were 99.1% (95% confidence interval [CI]=98%-99.6%) and 82.2% (95% CI=77.9%-85.7%), respectively, for benign mucinous tumors; 74.6% (95% CI=69.1%-79.4%) and 96.7% (95% CI=95.2%-97.8%), respectively, for mucinous borderline ovarian tumors; and 72.5% (95% CI=62.9%-80.3%) and 98.8% (95% CI=97.9%-99.3%), respectively, for invasive mucinous carcinomas. The multivariate analysis revealed that mixed tumor histology (odds ratio [OR]=2.8; 95% CI=1.3-6.3; p=0.012), tumor size >12 cm (OR=2.5; 95% CI=1.5-4.3; p=0.001), multilocular tumor (OR=2.9; 95% CI=1.4-6.0; p=0.006), and presence of a solid component in the tumor (OR=3.1; 95% CI=1.8-5.1; p<0.001) were independent risk factors for final pathological diagnosis upgrade., Conclusions: Mixed tumor histology, tumor size >12 cm, multilocular tumor, and presence of a solid component in the tumor were independent risk factors for final pathological diagnosis upgrade based on frozen section diagnosis., Competing Interests: No potential conflict of interest relevant to this article was reported., (Copyright © 2019. Asian Society of Gynecologic Oncology, Korean Society of Gynecologic Oncology.)

RNA yield and integrity are decisive for RNA analysis. However, it is often technically challenging to maintain RNA integrity throughout the entire laser capture microdissection (LCM) procedure. Since LCM studies work with low amounts of material, concerns about limited RNA yields are also important. Therefore, an LCM protocol was developed to obtain sufficient quantity of high-quality RNA for gene expression analysis in bone cells. The effect of staining protocol, thickness of cryosections, microdissected tissue quantity, RNA extraction kit, and LCM system used on RNA yield and integrity obtained from microdissected bone cells was evaluated. Eight-µm-thick frozen bone sections were made using an adhesive film and stained using a rapid protocol for a commercial LCM stain. The sample was sandwiched between a polyethylene terephthalate (PET) membrane and the adhesive film. An LCM system that uses gravity for sample collection and a column-based RNA extraction method were used to obtain high quality RNAs of sufficient yield. The current study focusses on mouse femur sections. However, the LCM protocol reported here can be used to study in situ gene expression in cells of any hard tissue in both physiological conditions and disease processes.

Objective: Histologic types and grades are critical in the diagnosis and treatment of spinal tumors. Intraoperative frozen section is a fast and easy method in confirming pathologic diagnosis during the operation. This study was undertaken to reveal the accuracy of intraoperative frozen section biopsy in order to make proper treatment plans., Methods: This retrospective study concerned patients who underwent spinal tumor surgeries from 1 January, 2012 to 31 December, 2016. Frozen section biopsy and permanent biopsy were compared, and cases that had differences were counted., Results: Thirty-seven cases out of 324 patients had discrepancies (11.4%). In discrepant cases 11 cases were ependymoma (29.7%) and 6 cases were schwannoma (16.2%). Among 34 patients who were finally diagnosed with an ependymoma, 11 cases had discrepancies, which was the highest mismatch rate among tumor final pathologic types. By frozen biopsy, astrocytoma (n = 5) and ependymoma (n = 5) turned out to be the most discrepant pathologic types and 16 frozen section biopsy cases were "null." Frozen biopsy astrocytoma (n = 5) mostly turned out to be ependymoma in 4 cases., Conclusions: Pathologic findings from frozen biopsy for spinal cord tumors could not be corresponded to final diagnosis, especially when the results of frozen biopsy were ependymoma or astrocytoma. Therefore careful decision making for treatment plans is required., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Context.—: In vivo microscopy (IVM) allows direct, real-time visualization of tissue histology in living patients without the need for tissue removal, processing, or staining. The IVM technologies in clinical use include confocal microscopy and optical coherence tomography. These technologies also show promise for use with pathology specimens (ex vivo microscopy [EVM]). However, few systems designed for EVM are commercially available, at least in part because of the lack of defined minimal functional requirements (FRs)., Objective.—: To develop minimal FRs for likely high-volume pathology applications of EVM., Design.—: The IVM Committee of the College of American Pathologists identified potential EVM pathology applications based on the published literature. A subcommittee of IVM and EVM early adopters and experts then defined FRs for the most likely EVM applications., Results.—: Potential EVM applications include assessment of margins, adequacy of needle biopsies and aspirates for diagnosis, and transplant tissues; selection of tissue for molecular studies or biorepository; and guidance in block selection from gross specimens. The first 3 applications were selected for development of FRs. The FRs were identified based on existing laboratory practices and guidelines and input from experts in the field and included device footprint and portability, specimen preparation, imaging time, field of view or resolution, morphologic diagnostic capability, yield, accuracy, ease of use, safety, and cost., Conclusions.—: Consensus was achieved on FRs that would accommodate the selected EVM applications. Publication and dissemination of those FRs will provide guidance to engineers, researchers, and vendors on how to optimally adapt IVM technologies for EVM for widespread adoption by pathologists.

Objectives: Piecemeal resection provides an innovative conceptual tool for margins surveillance because it entails the intraoperative evaluation of the whole resection margins and not just sample points, which should result in a better control of deep margins compared to en bloc resection. Although it is recognized that the intraoperative use of narrow band imaging (NBI) results in a better control of superficial margins, in this exploratory study we investigated whether NBI and piecemeal resection could be used in combination to improve margin control at both superficial and deep levels. Because piecemeal resection is based on frozen section analysis, we wanted to verify its reliability compared to definitive histological examination., Methods: The status of resection margins in a group of patients with oral and oropharyngeal cancers treated with NBI and laser CO2 piecemeal resection (group 1) was compared with that of an historical group of patients (group 2) treated with NBI and conventional en bloc resection. In group 1, sensitivity, specificity, and positive and negative predictive values were used to verify the rate of concordance between frozen section and definitive histology., Results: The difference between deep positive margins in the two groups was statistically significant (P = 0.042). The high sensitivity and specificity (94.6% and 94.7%, respectively) of frozen section analysis also demonstrated its reliability in the examination of larger samples corresponding to the whole margin., Conclusion: Even if our findings are limited by the small number of patients, we are confident that the combined use of NBI and piecemeal resection could represent an attractive surgical strategy to improve margin control., Level of Evidence: 2b Laryngoscope, 129:1810-1815, 2019., (© 2018 The American Laryngological, Rhinological and Otological Society, Inc.)

Frozen section examination (FSE) reshaped surgical pathology and is characterized by a high accuracy. Nonetheless pathologists can experience artefacts that can compromise or defer the diagnosis. We compared a commercial system, composed by a cryoembedder and a processor/stainer, to our FSE protocol. Feasibility of diagnosis as well as overall architecture, cytology, and staining, were scored under the following conditions: Traditional (liquid nitrogen freezing and manual staining), Only-Presto (liquid nitrogen freezing and commercial processor/stainer), Only-PrestoCHILL (cryoembedder and manual staining), and PrestoSystem (cryoembedder and processor/stainer). Scores were compared across the different experimental conditions. PrestoSystem had significantly higher scores than Traditional, Only-Presto or Only-PrestoCHILL in all categories (Wilcoxon test; all P-value <.001); similarly, also Only-Presto and Only-PrestoChill had significantly higher scores than Traditional in all categories. Only-PrestoCHILL had significantly higher scores than Only-Presto in Cytology and Architecture. In conclusion the control of pre-analytical variables provided reproducible results, of a higher quality., (Copyright © 2019 Elsevier GmbH. All rights reserved.)

Purpose: The aim of this study was to estimate the accuracy of intra-operative frozen section (FS) diagnosis during hysterectomy for early-stage endometrial cancer (EC)., Methods: At the Department of Obstetrics and Gynecology, University of Luebeck, between 2009 and 2014, the intra-operative FS pathology of 164 patients with pre-operative endometrial curettage, showing G1 or G2 endometrioid EC at an early clinical stage (FIGO I-II), was compared retrospectively with the final paraffin section reports. The accuracy of myometrial invasion (MI) in all patients and separately in stage FIGO I patients was calculated and the under- or overtreatment of the patients was analyzed. A subgroup analysis was performed focusing on the percentage of inadequate staging by FS with clinical consequences., Results: Concordance of FS and final pathology results in terms of FIGO stage was 85.2%, with an under-diagnosis rate of 14% and an over-diagnosis rate of 0.8%. The subgroup analysis rate of patients who were inappropriately operated using FS was 6.6%, while 3.3% underwent a secondary operation. The overall accuracy of FS in predicting MI was 93.3% and in patients with stage FIGO I, 92.7%. Sensitivity, specificity, PPV and NPV were 98.25%, 89.06%, 88.89% and 98.28%, respectively, and in stage FIGO I, 98.25%, 84.62%, 90.32% and 97.06%, respectively., Conclusion: The authors consider that intra-operative FS is a reliable diagnostic method to identify the clinical stage of EC and especially MI, to determine the necessity of lymphadenectomy. Further development of diagnostic techniques is essential to maximize diagnostic accuracy.

Background: Pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) with paraaortic lymph nodes metastases (PALN +) is associated with poor survival. Still, there are no current guidelines advocating systematic detection of PALN+., Methods: All consecutive patients who underwent surgical exploration/resection with concurrent paraaortic (group 16) lymphadenectomy for PDAC between 2009 and 2016 were considered for inclusion. Resection was systematically aborted in case of intraoperative PALN + detection. Diagnostic performance of preoperative imaging upon blind review and intraoperative PALN dissection with frozen section (FS) for PALN detection were evaluated. Additionally, the prognostic significance of PALN + on overall survival (OS) was analyzed., Results: Over the study period, among 129 patients undergoing surgery for PDAC, 113 had intraoperative PALN dissection with FS analysis. Median number of resected PALN was 3 (range, 1-15). Overall, PALN+ was found in 19 patients (16.8%). Upon blind review, preoperative imaging performed poorly for PALN + detection with a low agreement between imaging and final pathology (Kappa-Cohen index<0.2). In contrast, PALN FS showed high detection performances and strong agreement with final pathology (Kappa-Cohen index = 0.783, 95%CI 0.779-0.867, p < 0.001). Regarding survival outcomes, there was no difference between patients with PALN+ and patients not resected in the setting of liver metastases or locally unresectable disease found at exploration (p = 0.708)., Conclusions: Before PD for PDAC, intraoperative PALN dissection and FS analysis yields accurate PALN assessment and allows appropriate patient selection. This should be routinely performed and aborting resection should be strongly considered in case of PALN+., (Copyright © 2019 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

Purpose: The optimal timing of reimplantation of two-stage exchange arthroplasty for periprosthetic joint infection remains unknown. The purpose of the study was to (1) evaluate performance of combination of serum erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and frozen section in predicting persistent infection at the time of second-stage hip reimplantation and (2) compare accuracies of 5 and 10 polymorphonuclear neutrophils (PMNs) per high power field (HPF) as the threshold of frozen section., Methods: We retrospectively reviewed 97 two-stage exchange hip arthroplasties from 2012-2016. Persistent infection at time of reimplantation was diagnosed using the Musculoskeletal Infection Society (MSIS) criteria. Two diagnostic models were developed. Model 1 utilized ESR, CRP, and > 5 PMNs/HPF on frozen section. Model 2 utilized ESR, CRP, and > 10 PMNs/HPF. Receiver operating characteristic (ROC) curves of the two models were generated, and areas under the curves (AUCs) were compared. A set of sensitivity analysis, using the Delphi-based consensus criteria for treatment success, was conducted to verify the accuracy of our models., Results: The overall rate of infection at reimplantation was 14.4%. AUCs for models 1 and 2 were 0.709 (95% confidence interval [CI], 0.557-0.852) and 0.697 (95% CI, 0.529-0.847), respectively. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 57.1%, 88.0%, 44.4%, and 92.4%, respectively, in model 1 and 42.9%, 96.4%, 66.7%, and 90.9%, respectively, in model 2. Models 1 and 2 had no significant difference in predictive values (p = 0.821). Results remained robust in the sensitivity analysis., Conclusions: This study reveals that the combination of serum ESR, CRP, and frozen section has limited diagnostic value in predicting persistent infection at reimplantation. Additionally, no significant difference in accuracies between 5 and 10 PMNs/HPF as the threshold of frozen section were found. There is a need for timely biomarkers with higher accuracy in diagnosing infection before reimplantation.

Background: Evaluation of core needle biopsies (CNB) is a standard procedure for the diagnosis of breast cancer. However, tissue processing and image preparation is a time- consuming procedure and instant on-site availability of high-quality images could substantially improve the efficacy of the diagnostic procedure. Conventional microscopic methods, such as frozen section analysis (FSA) for detection of malignant cells still have clear disadvantages. In the present study, we tested a confocal microscopy scanner on fresh tissue from CNB with intention to develop an alternative device to FSA in clinical practice., Patients and Methods: In 24 patients with suspicious breast lesions standard of care image-guided biopsies were performed. Confocal images have been obtained using the Histolog™ Scanner and evaluated by two independent pathologists. Hematoxylin-Eosin (H&E) histological sections of the biopsies were routinely processed in a blinded fashion with respect to the confocal images., Results: In total 42 confocal images were generated from 24 biopsy specimens, and available for analysis within a few minutes of taking the biopsy. This resulted in 2 × 42 = 84 pathologic evaluations. In four cases, a pathologic diagnosis was not possible with confocal microscopy. An exact correlation based on the B-classification was reached in 41 out of 80 examinations and in another 35 cases in a broader sense of correspondence definition (i.e. malignant vs. benign)., Conclusions: As a reliable on-site method, the Histolog™ Scanner provides a visualization of cellular details equivalent to the H&E standards, permitting rapid and accurate diagnosis of malignant and benign breast lesions. Furthermore, this device offers great potential for immediate margin analysis of specimen in breast conserving therapy.

Background and Objectives: Recent studies show that whole specimen intraoperative frozen section analysis (WIFSA) is a reliable method for margin analysis in basal cell carcinoma (BCC) and has low recurrence rates after five-years follow-up. There are no studies with longer follow-up. Our aim is to present long-term recurrence rates after WIFSA., Materials and Methods: All patients with a facial BCC receiving excision with WIFSA between 1992 and 2007 were evaluated. Recurrence rates were examined for primary BCC (pBCC), recurrent BCCs (rBCC), and the different histological subtypes. The accuracy of WIFSA was assessed by comparing with formalin-fixed paraffin-embedded section analysis., Results: A total of 1140 patients with 1265 BCCs underwent excision with WIFSA, with a median and maximum follow-up of 10 and 25.3 years, respectively. Of all tumors, 90.0% were primary. Excisions were radical after an average of 1.4 excision rounds;5, 10, and 15-year recurrence rates for pBCCs are 3.3%, 5.1%, and 7.3%, respectively. An aggressive growth pattern and rBCCs are associated with more recurrences. The accuracy of WIFSA is 98.4%., Conclusions: WIFSA provides a highly accurate analysis and has a low recurrence rate for primary BCCs. The increasing recurrence rates over time imply 5 years of follow-up may be insufficient., (© 2019 Wiley Periodicals, Inc.)

Background: Intraoperative frozen examination is clinically important for negative margin confirmation in cancer surgery. We investigated the diagnostic accuracy of frozen-section assessment and risk factors for positive resection margins by studying gastric cancer specimens from 1115 patients treated at our hospital., Methods: The results of gastric cancer patients who had undergone intraoperative margin assessment, employing frozen examination, with curative intent in our unit between 2000 and 2017 were retrospectively analyzed. Frozen section assessments were compared with the corresponding permanent section assessments to evaluate the accuracy, sensitivity, and specificity of the former. The causes of discordances between two assessments were examined. In addition, risk factors associated with positive margins were identified., Results: In total, 1241 specimens were obtained from the 1115 patients. The accuracy, sensitivity, and specificity of frozen-section assessments were 99.4%, 99.5%, and 97.8%, respectively. There were eight discordant cases. Two false-negative cases required another gastrectomy after final pathological diagnosis because of missed neoplastic cells. Six false-positive cases underwent unnecessary additional resection due to false positive results. In our frozen series, 89 cases had a positive margin on permanent section. Multivariate regression analysis of patients with positive surgical margins revealed large diameter (≥ 50 mm) and T4 tumor to be independent risk factors., Conclusions: Intraoperative frozen examination is a highly accurate method that is useful for achieving negative margins. This procedure is especially recommended for patients with a tumor larger than 50 mm in maximum diameter or serosal invasion to confirm a negative margin.

Background: Open biopsy of bone is the diagnostic benchmark for the diagnosis of skeletal lesions. Intraoperative pathology consultation with frozen section analysis is commonly performed to confirm adequacy of lesional tissue and guide intraoperative decision making. The purpose of this study was to determine the accuracy and clinical utility of intraoperative frozen section during open bone biopsy., Methods: A retrospective review of 485 open biopsies of osseous lesions from 474 patients between 1997 and 2014 was performed. Pathology reports, operative notes, and prebiopsy imaging were assessed to determine the accuracy rates of frozen section analysis compared with final pathology. Pearson chi-squared and Fisher exact tests were performed to compare the accuracy and clinical utility rates based on soft-tissue extension, previous biopsy, lesional consistency, disease, and location., Results: Overall diagnostic yield of open bone biopsy was 95.3%. Frozen section analysis was accurate in 54.2%, equivocal positive in 21.2%, equivocal negative in 21.0%, and incorrect in 3.5% of cases. Previous nondiagnostic biopsy and the type of disease were found to have statistically significant effects on the accuracy of frozen section analysis., Conclusion: Frozen section analysis was diagnostic in approximately one half of open biopsy cases. Additional information in equivocal positive results suggests that frozen section analysis is helpful for intraoperative decision making (clinical utility) in 75.4% of cases., Level of Evidence: Retrospective review level IV.

Objective: Intra-operative frozen section (IFS) can provide an instinct guide for treatment of ovarian tumors intra-operatively, though limitations exist. This study intended to evaluate the diagnostic performance of IFS and possible clinicopathological factors influencing the diagnostic accuracy of IFS., Methods: A retrospective review of IFS of ovarian lesions from 2006 to 2016 was done. The diagnostic performance of benign, borderline, and malignant IFS diagnosis was evaluated. Logistic regression analysis was used to assess the influence of clinicopathological parameters on the likelihood of underdiagnosis., Results: There were 1143 consecutive cases during the study period. The overall accuracy was 93.7%. For benign diagnoses, the IFS diagnostic accuracy, sensitivity, and specificity were 97.20%, 100%, and 92.51%, respectively. If borderline and malignant diagnoses were considered as a single group, the IFS diagnostic accuracy was 97.20%, with 92.51% sensitivity and 100% specificity. At univariate regression analysis, intact capsules at time of delivery (OR unadj = 1.9), stage I lesions (OR unadj = 3.76) and ultrasound (USG) score 0 (OR unadj = 2.52) were positively associated with underdiagnosis. Further multivariate analysis showed that only stage I lesions (OR = 3.62) and USG score 0 (OR = 2.32) were positively associated with underdiagnosis. For the cases with underdiagnosed IFS, 54% (34/63) received incomplete primary staging surgery., Conclusions: The study demonstrated that IFS provided excellent specificity to differentiate borderline or malignant tumors from benign lesions. IFS in early-stage ovarian cancers needs to be interpreted with caution, though IFS is most important for this group of lesions. A reliable IFS diagnosis often requires efficient communication between surgeons and pathologists., Competing Interests: Competing interests: None declared., (© IGCS and ESGO 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Aims: Telepathology uses digitised image transfer to allow off-site reporting of histopathology slides. This technology could facilitate the centralisation of pathology services, which may improve their quality and cost-effectiveness. The benefits may be most apparent in frozen section reporting, in which turnaround times (TATs) are vital. We moved from on-site to off-site telepathology reporting of thoracic surgery frozen section specimens in 2016. The aim of this study was to compare TATs before and after this service change., Methods and Results: All thoracic frozen section specimens analysed 4 months prior and 4 months following the service change were included. Demographics, operation, sample type, time taken from theatre, time received by laboratory, time reported by laboratory, TAT, frozen section diagnosis, final histopathological diagnosis and final TNM staging were recorded. The results were analysed with spss statistical software version 24. In total, there were 65 samples from 59 patients; 34 before the change and 31 after the change. Specimens included 51 lung, six lymph node, three bronchial, three chest wall and two pleural biopsies. Before the change, the median TAT was 25 min [interquartile range (IQR) 20-33 min]. No diagnoses were deferred. No diagnoses were changed on subsequent paraffin analysis. After the change, with the use of digital pathology, the median TAT was 27.5 min (IQR 21.75-38.5 min). This difference was not significant (P = 0.581). Diagnosis was deferred in one case (3.23%). There was one (3.23%) mid-case technical failure resulting in the sample having to be transported by courier, resulting in a TAT of 106 min. No diagnoses were changed on subsequent paraffin analysis., Conclusions: There was no significant difference in reporting times between digital technology and an on-site service, although one sample was affected by a technical failure requiring physical transportation of the specimen for analysis. Our study was underpowered to detect differences in accuracy., (© 2018 John Wiley & Sons Ltd.)

Background and purpose - For decision-making (aseptic vs. septic), surgeons rely on intraoperatively available tests when a periprosthetic joint infection (PJI) cannot be confirmed or excluded preoperatively. We compared and evaluated the intraoperative performances of the frozen section and the alpha defensin lateral flow test in the diagnosis of PJI. Patients and methods - In this prospective study, consecutive patients with indicated revision surgery after arthroplasty were included. Patients were classified as having PJI using the MusculoSkeletal Infection criteria. The presence of alpha defensin was determined using the lateral flow test intraoperatively. During revision surgery, tissue samples were harvested for frozen and permanent section. Analysis of diagnostic accuracy was based on receiver-operating characteristics. Results - 101 patients (53 hips, 48 knees) were eligible for inclusion. Postoperatively, 29/101 patients were diagnosed with PJI, of which 8/29 cases were definitely classified as septic preoperatively. Of the remainder 21 septic cases, the intraoperative alpha defensin test and frozen section were positive in 13 and 17 patients, respectively. Sensitivities of the alpha defensin test and frozen section were 69% and 86%, respectively. The area under the curves of both tests showed a statistically significant difference (p = 0.006). Interpretation - The frozen section showed a significantly higher performance compared with the alpha defensin test and a near perfect concordance with the definitive histology, and therefore remains an appropriate intraoperative screening test in diagnosing PJI. Although the sensitivity of the alpha defensin test was lower compared with that of frozen section, this test is highly specific for confirming the diagnosis of PJI.

Introduction: Patients diagnosed with lung cancer may require immediate evaluation of mediastinal lymph nodes to determine treatment plan. Typically, frozen section (FS) analysis has been used, but this analysis can be time-consuming and uses more tissue than touch preparation (TP) cytologic analysis. TP accuracy has been studied in other organs, but no prospective studies comparing TP to FS have been performed on mediastinal lymph nodes in lung cancer. Our goal was to compare the accuracy of TP to FS in these cases., Materials and Methods: After obtaining institutional review board approval, all patients undergoing mediastinal lymph node evaluation for a diagnosis of lung cancer were asked to participate. If consent was given, TP and FS analyses were performed on all mediastinal lymph node stations in all patients and compared to permanent hematoxylin and eosin analysis. Data were collected prospectively., Results: Twenty patients were enrolled. Mean age was 67.7 years. Fifty-five percent (11 of 20) of patients were men. The mean number of lymph node stations sampled in each patient was 3.4. In predicting the stage of the patient, TP had a sensitivity and specificity of 95% and 100%, respectively. FS had a lower sensitivity, 85%, and a specificity of 100%. On permanent analysis, metastatic foci ranged in size from 0.15 mm to 1.5 mm., Conclusions: TP was more sensitive than FS in detecting mediastinal lymph node metastases. The technical difficulty of obtaining full-thickness sections without creating significant artifact may contribute to the lower sensitivity of FS in detecting micrometastases., (Copyright © 2018 American Society of Cytopathology. Published by Elsevier Inc. All rights reserved.)

We wanted to discuss our experiences in the approach to borderline ovarian tumors, which constitute a group different from epithelial ovarian tumors with respect to their biological structure in line with retrospective information gathered from our cases. A total of 25 patients operated on for the indication of adnexal masses diagnosed as borderline ovarian tumors based on frozen section results were included in our study. Patient age, tumor diameter, tumor markers and surgeries performed were discussed in the light of the literature. Statistical analyses were performed using the SPSS software. The patient mean age was 43.84±11.34 years. The mass was localized in the right (n=13), left (n=11) or both (n=1) adnexal regions. The mean tumor diameter was 12.9±5.84 cm. Histopathologic examination established the diagnosis of serous borderline (n=14 patients) and mucinous borderline (n=11) ovarian tumors. Although the results of our study are consistent with current literature data, a greater number of current studies should be performed on borderline ovarian tumors, which are defined as a class of tumors different from epithelial ovarian tumors.

Immunohistochemistry (IHC) specifically localizes proteins in cells and tissues, but methodologies vary widely. Therefore, we performed a methodological IHC optimization and validation study. First, we compared advantages and disadvantages of cryostat sections versus paraffin sections. Second, we compared and optimized antigen retrieval in paraffin sections using citrate buffer and Tris/EDTA buffer. Third, aminoethyl carbazole (AEC) and 3,3'-diaminobenzidine (DAB) were tested as horseradish peroxidase (HRP) substrates to obtain a water-insoluble coloured end product to visualize antigens. Fourth, secondary antibodies conjugated with either mono-HRP or poly-HRP were compared. The study was performed using serial sections of human tonsil. IHC was performed with primary antibodies against endothelial cell marker CD31, smooth muscle actin (SMA), chemokine stromal-derived factor-1α (SDF-1α) and its receptor C-X-C receptor type 4 (CXCR4), macrophage marker CD68 and proliferation marker Ki67. DAB rather than AEC, and cryostat sections rather than paraffin sections gave optimum staining at highest primary antibody dilutions, whereas tissue morphology in paraffin sections was superior. Loss of antigenicity in paraffin sections by formaldehyde fixation, heat and/or masking of epitopes was counteracted by antigen retrieval but not for all antigens. Two out of six antigens (CD31 and CD68) could not be retrieved irrespective time and type of retrieval. Tris-EDTA was superior to citrate buffer for antigen retrieval. The use of mono-HRP or poly-HRP depended on the affinity of the primary antibody for its antigen. We conclude that IHC methodology optimization and validation are crucial steps for each antibody and each research question., (Copyright © 2018 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Background: Frozen section (FS) is often performed when histopathological evaluations are urgently required for implementation of therapeutic measures. In dermatology, this method is most commonly used to evaluate excision margins of tumors. FS are also routinely employed to differentiate toxic epidermal necrolysis from staphylococcal scalded skin syndrome. However, little is currently known about the performance of FS in the diagnosis of inflammatory dermatoses., Objectives: To compare histopathological diagnoses in a series of patients with a clinical diagnosis of an inflammatory dermatosis for which FS and paraffin-section (PS) specimens were obtained on the same day., Methods: We conducted a single-center retrospective analysis of 43 cases. All histological slides were reviewed by a single dermato-pathologist. Concordance was calculated between FS and PS., Results: Patients were divided into three groups according to diagnosis: papulosquamous diseases (group I), drug eruptions (group II), and a heterogeneous group (group III) that included cases of bullous vasculitis and Sweet syndrome. Among the three groups, the results of FS and of PS were discordant only in five cases (5/43, 11.6%). Compared to PS, FS had a sensitivity of 92.9% [95% confidence interval (95%CI) 64.17-99.63%] and a specificity of 100% in group I, sensitivity of 90.9% (95%CI 57.12-99.52%) and specificity of 100% in group II, and sensitivity of 83.33% (95%CI 60.78-94.16%) and specificity of 100% in group III. The degree of agreement between the results of the FS and of the PS was almost perfect (kappa = 0.95, 0.93 and 0.85 respectively)., Conclusions: This study suggests that FS is a valid approach for the rapid diagnosis of inflammatory dermatoses. This method is as specific as PS, although it is less sensitive.

Background: Routine use of frozen section (FS) is a costly procedure and sparsely available in resource poor countries. A proper cost benefit analysis may help to reduce its routine use and would empower surgeons to perform oral cancer surgeries without having FS facility. FS is performed to identify microscopic spread beyond gross disease that cannot be assessed clinically., Objective: Our primary aim was to determine the cost benefit analysis of FS in the assessment of margins in oral cavity squamous cell carcinoma (OSCC)., Materials and Methods: Retrospective study of prospectively collected data of 1311 consecutive patients who were operated between January 2012 and October 2013. The gross and microscopic margin status of each patient was extracted from the patient's chart. The cost estimates were performed to calculate the financial burden of FS as well as expenses incurred on adjuvant treatment resulting from inadequate margins., Result: Microscopic spread changed the gross margin status in 5.2% (65/1237) patients. Of this entire cohort of 1237 patients, FS helped 29 (2.3%) patients to achieve tumor free margin, and it changed the adjuvant treatment plan in 9 (0.7%) patients. The cost of FS for each patient was INR 11052. The cost-benefit ratio of FS was 12:1. Gross examination alone could have identified majority of the inadequate margins., Conclusion: Frozen section for assessment of margin status bears poor cost-benefit ratio. Meticulous gross examination of the entire surgical specimen is sufficient to identify majority of inadequate margins., Competing Interests: There are no conflicts of interest.

Many cancers harbor a large fraction of nonmalignant stromal cells intermixed with neoplastic tumor cells. While single-cell transcriptional profiling methods have begun to address the need to distinguish biological programs in different cell types, such methods do not enable the analysis of spatial information available through histopathological examination. Laser capture microdissection offers a means to separate cellular samples based on morphological criteria. We present here an optimized method to retrieve intact RNA from laser capture microdissected tissue samples, using pancreatic ductal adenocarcinoma as an example, in order to separately profile tumor epithelial and stromal compartments. This method may also be applied to nonmalignant tissues to isolate cellular samples from any morphologically identifiable structure.

Immunohistochemistry (IHC) is a routinely used technique in clinical diagnosis of pathological conditions and in basic and translational research. It combines anatomical, immunological, and biochemical methods and relies on the specific binding of an antibody to an antigen. Using the technique with mineralized tissues is more challenging than with soft tissues. Demineralizing the samples allows for embedding in paraffin wax, and also facilitates cryosectioning. This chapter describes methods for IHC on formaldehyde-fixed, demineralized, paraffin-embedded, or frozen sections to detect antigens in skeletal tissues.

Cutting frozen sections is a technique that allows for the rapid diagnosis of unfixed frozen tissue. A thin slice of tissue is cut from a frozen biospecimen and then stained typically with hematoxylin and eosin. The applications of this technique range from clinical diagnosis to quality assurance in the procurement or the use of biobanking specimens. It is important that the quality of the frozen section is of the highest possible caliber in order to optimize the pathologist's interpretation, whether the result is used for surgical management or to validate the tissue being collected for research. Herein, we describe a step-by-step method to cut frozen sections.

Rationale: Adenoid cystic carcinomas (ACCs) are malignant tumors and occur in the major and the minor salivary glands. ACCs are rare in the larynx., Patient Concerns: A 55-year-old female patient who presented with a 12 months history of paraesthesia pharynges and hoarseness for 4 months. Laryngoscopy showed an endophytic lesion in the right supglottic area with no laryngeal stenosis. And magnetic resonance imaging (MRI) confirmed the presence of a submucosal mass in the supglottic area. Supporting laryngoscope was performed under general anesthesia and a lesion biopsy obtained., Diagnoses: The lesion was sent for frozen-section biopsy, which shows the lesion was the epithelial-derived tumors of salivary gland, but it was impossible to identify the relationship between the tumor and the surrounding normal tissue, and to judge the nature of the tumor further. So, the lesion was sent for the second frozen-section biopsy, an ACC of the larynx was confirmed and margins were negative., Interventions: The patient underwent partial laryngectomy., Outcomes: The patient was doing well except hoarseness during the follow-up period with no evidence of disease recurrence or metastasis for 17 months post-operatively., Lessons: Laryngeal ACC is a rare entity. When the nature of lesion cannot be confirmed, multiple biopsies may be required for confirm the diagnosis of pathology. It not only reduces patient's waiting time for surgery, but also define the diagnosis and surgical removal of lesion through a single anesthesia.

Oil Red O is a useful tool to assess donor liver steatosis on frozen sections during transplantation. Steatosis is a frequent finding in liver evaluation during transplantation, accounting for 9% to 26% of biopsied donor liver. The degree of macrovesicular steatosis is classified as mild, moderate, and severe; the latter is considered an absolute contraindication to liver transplantation because it is associated with poor allograft outcome. Because of the scarcity of organs, there is a debate whether livers with less severe macrovesicular steatosis are still suitable for transplant. Consequently, tools or methods that allow a more accurate intraoperative assessment of steatosis on frozen sections are mandatory. The aim of this study is to improve intraoperative evaluation of steatosis during transplantation using Oil Red O stain on liver biopsies., Methods: Twenty consecutive liver biopsies of donors were collected during transplantation procedures from September 2017 to February 2018 at the Institute of Pathology of the University and Hospital Trust of Verona, Italy. Each liver biopsy was cut at a different thickness (3, 5, and 8 μm) and stained with both Oil Red O and conventional hematoxylin and eosin for intraoperative consultation. The degree (percentage of hepatocytes involved) of fatty changes was recorded. The results obtained during the intraoperative consultation were finally compared with the formalin-fixed and paraffin-embedded permanent section., Results: Assessment of steatosis on hematoxylin and eosin frozen sections was reported as mild in 17 cases (85%), moderate in 2 cases (10%) and severe in 1 case (5%). Oil Red O frozen sections reported the following results: mild steatosis in 16 cases (80%), moderate in 2 cases (10%), and severe in 2 cases (10%). The percentage of liver steatosis obtained with Oil Red O was consistent in all cases with that of the permanent sections. The staining procedure for Oil Red O required approximately 18 minutes., Conclusions: Oil Red O special stain is a fast and inexpensive tool to improve the assessment of steatosis on frozen biopsies during liver transplantation., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Angiomyxomas are rare soft tissue neoplasms rich in myxoid matrix and blood vessels that typically present as nodules on the trunk, head, and limbs in adults. They are classified as either cutaneous or aggressive based on histological findings and extent of local growth. There are less than 150 reported cases in the literature. In this case report we describe the first paratesticular case of a cutaneous angiomyxoma in a pediatric patient, who presented with a transilluminating paratesticular mass consistent with a hydrocele, but showed solid and vascular features on ultrasound., (Copyright © 2018. Published by Elsevier Inc.)

Objective Identify methods to improve the frozen-section diagnosis of acute invasive fungal rhinosinusitis. Study Design Biopsies with frozen section for suspected acute invasive fungal rhinosinusitis were reviewed to identify causes for missed diagnoses and evaluate methods for potential improvement. Setting All aspects of the study were performed at the Penn State Milton S. Hershey Medical Center. Subjects and Methods All frozen sections performed for suspected acute invasive fungal rhinosinusitis between 2006 through 2017 were reviewed with their diagnoses compared to the final diagnoses. Sensitivity and specificity were determined for each biopsy specimen to evaluate the diagnostic method and for each patient for its effectiveness on outcome. Causes for frozen-section failures in diagnosis were identified. A periodic acid-Schiff stain for fungus (PASF) was modified for use on frozen tissue (PASF-fs) and applied both retrospectively and prospectively to frozen sections to determine its ability to identify undetected fungus and improve diagnostic sensitivity. Results Of 63 biopsies positive for acute invasive fungal rhinosinusitis, 51 were diagnosed on frozen section, while 61 were identified by including the novel PASF-fs stain, reducing the failure rate from 19% to 3%. Of 41 cases that were positive, 34 were diagnosed on frozen section. Of the 7 that were not, 5 were identified by including the PASF-fs, reducing the failure rate from 17% to 5%. Conclusions Frozen section interpretation of biopsies for suspected acute invasive fungal rhinosinusitis using a PASF-fs stain should enable a rapid and accurate diagnosis with improved outcomes by shortening the time to surgery.

Background: Intraoperative frozen sections (FS) of sentinel lymph nodes (SLN) were evaluated to avoid the need for deferred axillary lymph node dissection (ALND) in patients with early breast cancer (EBC). However, FS has low sensitivity for detecting micro-metastases (<2 mm), resulting in patients who later undergo deferred ALND. The aim of the study was to determine the best clinical approach for selecting patients who would derive real benefit from ALND, as well as to minimize the functional and psychological damage caused by delayed surgery, and the risk of undertreating EBC patients., Methods: This study evaluated 1453 patients with early breast cancer (EBC) who underwent SLN biopsy, FS and definitive evaluation. Causes of discrepancies between SLN biopsy and FS results and the need for further surgery were evaluated., Results: A total of 1226 (86%) patients underwent FS; of these patients, 146 (11.9%) were false negatives. The global sensitivity of FS in detecting both macro and micrometastases was 53.7%. Although ACOSOG Z0011 criteria found that ALND could be avoided in 236 patients, 40 (17%) of these had >3 positive axillary lymph nodes. In contrast, application of the IBCSG 23-10 trial criteria, found that only three patients (3.1%) had >3 positive axillary lymph nodes., Conclusions: FS has a low sensitivity in detecting micrometastases (19%), but a reasonable sensitivity for macrometastases (75%). Most false negatives were smaller metastases (mean 2.1 mm) and more likely in patients with infiltrating lobular carcinoma. Retrospective modelling of the IBCSG 23-10 criteria reduced the percentage of patients requiring deferred surgery from 12% to 4%. Guidelines recommend irradiation of lymph node drainage stations in patients with ≥4 axillary metastatic lymph nodes. Omission of ALND from 40% of patients who met Z0011 criteria would have resulted in their undertreatment. This risk decreases to 3% by omitting axillary clearing only in patients with micrometastases., (Copyright © 2017 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.)

Introduction: Intraoperative frozen section lymph node assessment helps to predict axillary lymph node metastasis in breast cancer. However, the accuracy of this frozen section analysis may vary among institutions. This study describes our institution's experience in intraoperative analysis of sentinel lymph node and aims to determine the accuracy, sensitivity and specificity of our assessment., Materials and Methods: We retrospectively analysed the histopathological material and data from 82 breast cancer patients diagnosed over a period of four years who underwent intraoperative frozen section evaluation of sentinel lymph nodes., Results: Frozen section analysis detected metastasis in 13 out of 82 cases and definitive pathological examination on the paraffin section confirmed these positive findings. There was no false positive case (specificity of 100%). The true positive cases comprised seven macrometastases, five micrometastases and one isolated tumour cells. Sampling error was noted in two cases in which the malignant cells were only present in the deeper final paraffin sections (false negative rate of 13.3%). The test sensitivity was 86.7% and the accuracy rate was 97.5%. These findings are comparable to other published data., Conclusion: Intraoperative frozen section analysis is a safe and reliable method for assessment of sentinel lymph node. Knowledge on limitation of frozen section analysis with diligent evaluation of frozen section specimen will be beneficial in reducing interpretation error.

Frozen section telepathology interpretation experience has been largely limited to practices with locations significantly distant from one another with sporadic need for frozen section diagnosis. In 2010, we established a real-time nonrobotic telepathology system in a very active cancer center for daily frozen section service. Herein, we evaluate its accuracy compared to direct microscopic interpretation performed in the main hospital by the same faculty and its cost-efficiency over a 1-year period. From 643 (1,416 parts) cases requiring intraoperative consultation, 333 cases (690 parts) were examined by telepathology and 310 cases (726 parts) by direct microscopy. Corresponding discrepancy rates were 2.6% (18 cases: 6 [0.9%] sampling and 12 [1.7%] diagnostic errors) and 3.2% (23 cases: 8 [1.1%] sampling and 15 [2.1%] diagnostic errors), P = .63. The sensitivity and specificity of intraoperative frozen diagnosis were 0.92 and 0.99, respectively, in telepathology and 0.90 and 0.99, respectively, in direct microscopy. There was no correlation of error incidence with postgraduate year level of residents involved in the telepathology service. Cost analysis indicated that the time saved by telepathology was $19,691.00 over 1 year of the study period, whereas the capital cost for establishing the system was $8,924.00. Thus, real-time nonrobotic telepathology is a reliable and easy-to-use tool for frozen section evaluation in busy clinical settings, especially when frozen section service involves more than one hospital, and it is cost-efficient when travel is a component of the service., (Copyright © 2018 Elsevier Inc. All rights reserved.)

BACKGROUND The aim of this study was to compare the clinical outcome in patients with pancreatic ductal adenocarcinoma who underwent frozen section and paraffin section histology of the surgical resection margins during pancreaticoduodenectomy. MATERIAL AND METHODS Frozen section and routine paraffin section histopathology were performed using the following categories: R0 (no tumor cells at the surgical resection margin), R1 (tumor cells at, or within 1 mm, of the surgical resection margin), and R2 (tumor seen macroscopically at the surgical resection margin). R1 and R2 patients underwent additional resection to achieve R0. RESULTS Of 346 patients who underwent pancreaticoduodenectomy, frozen section histology showed positive resection margins in 22 patients (9.2%) and paraffin section histology was positive in 20 patients (8.4%). The OS was nine months in frozen section-positive patients and 20 months in frozen section-negative patients (p=0.001). The OS rates were significantly different between the paraffin section-positive and paraffin section-negative patients (11 months vs. 21 months) (p=0.001). Univariate and multivariate analysis showed that increased tumor size, high tumor grade, lymph node metastases, a positive superior mesenteric artery and retroperitoneal margin, and a positive resection margin on frozen section were significantly correlated with reduced OS (p<0.05). Twenty-two patients with positive resection margins on frozen section histology underwent further resection; R0 was achieved in 14 patients, with no significant difference in OS. CONCLUSIONS For patients who underwent pancreaticoduodenectomy for pancreatic carcinoma with positive resection margins on frozen section, further surgical resection to achieve R0 had no significant positive impact on OS.

The number of released free cholesterol crystal emboli (fCCE) and their role during percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS) have not been documented yet. Furthermore, fCCE manifesting in the coronary lumen following plaque rupture has been historically overlooked owing to the standard tissue preparation for light microscopy which uses ethanol as a dehydrating agent that can dissolve fCCE, leaving behind empty tissue. In this case report, we evaluated fCCE released during PCI for ACS and their relationship with myocardial injury and coronary artery obstruction on the H&E-stained sections by using polarised light microscopy. To our knowledge, there has been no mention of the visibility of fCCE on H&E-stained frozen polarised sections before., Competing Interests: Competing interests: KK, who is the president of Inter-tec Medicals, Co., developed non-obstructive angioscopy. SK is a technical consultant for Nemoto Kyorin-do Co., (© BMJ Publishing Group Limited 2018. No commercial re-use. See rights and permissions. Published by BMJ.)

For squamous cell carcinoma (SCC) treated using Mohs micrographic surgery (MMS), interpretation of haematoxylin and eosin-stained frozen sections can be challenging. In these situations, ancillary use of immunostaining is a useful tool for the Mohs surgeon. However, use of immunostaining in MMS laboratories is limited, mainly because current manual immunostaining platforms are subject to operator error, and automated immunostaining, albeit accurate, is too slow for inclusion in MMS. In this report, we describe a novel 1-hour protocol for rapid frozen section immunocytochemistry, using the pancytokeratin markers AE1/AE3. This protocol has been specifically designed to integrate the speed of manual techniques and the accuracy of automated platforms, making it a valuable addition to the MMS laboratory. We propose that in selected or histologically challenging cases, there is a role for the use of this novel protocol, allowing the Mohs surgeon to more confidently declare tumour clearance, thus preventing further unnecessary surgery and preserving healthy tissue., (© 2018 British Association of Dermatologists.)

Purpose: To demonstrate a novel frozen section analysis technique during robot assisted radical prostatectomy with 2 distinct advantages: evaluation of the entire circumference and easier reconstruction for whole mount evaluation., Material and Methods: Istanbul Preserve was performed on patients who underwent robotic prostatectomy with nerve sparing between 10/2014 and 7/2016. Gland was sectioned at 3-4mm intervals from apex to bladder neck. Entire tissue representing margins (except for the most anterior portion) was circumferentially excised and microscopically analyzed. In margin positivity, approach was individualized based on extent of positive margin and Gleason pattern. A matched cohort was established for comparison. Retrospective analysis of a prospectively maintained database was performed. Impact of FSA on PSM rate was primarily assessed., Results: Data on 170 patients was analyzed. Positive surgical margin was reported in 56(33%) on frozen section. Neurovascular bundle was partially or totally resected in 79% and 18%. Conversion of positive margin to negative was achieved in 85%. Overall positive margin rate decreased from 22.5% to 7.5%. Nerve sparing increased from 87% to 93%. Location of positive margin at frozen was at the neurovascular bundle area in 39%; thus Istanbul Preserve detected 61% additional margin positivity compared to other techniques. Reconstruction for whole mount was easy., Conclusion: Istanbul Preserve is a novel technique for intraoperative FSA during RARP allowing for microscopic examination of the entire prostate for margin status and easy re-construction for whole mount examination. It guarantees safer margins together with increased rate of nerve sparing., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Introduction: Frozen section helps in rapid intra-operative diagnosis. It is commonly used during surgical procedures to detect malignancy so that modifications of surgery can be decided at the time of surgery on the table. Frozen section is also performed for evaluation of surgical margins and detection of lymph node metastasis. In addition it is applied for detection of unknown pathological processes.The objective of this study was to assess the accuracy of frozen section diagnosis in comparison to gold standard histopathological diagnosis and to find concordance and discordance rate of frozen section with histopathological report., Methods: This was a cross sectional study of 41 frozen section samples done in the department of pathology of BP Koirala Institute of Health Sciences from September 2014 to August 2015. All frozen section samples with their permanent tissue samples sent for final histopathological evaluation were included in the study., Results: The overall accuracy of frozen section diagnosis was 97%. The sensitivity was 94%, specificity was 87%, positive predictive value was 90% and negative predictive value was 93%. The concordance rate was 90.2% and the discordance rate was 9.8%., Conclusions: The results of frozen section varied in different organ systems and the common cause of discrepancy in our study were the gross sampling error and the interpretational error.

Objective: To investigate haptoglobin within ovarian cyst fluid (OCF) as a diagnostic biomarker for epithelial ovarian cancer (EOC) and develop an in vitro diagnostic point-of-care device test (IVDPCT) for use in the operating theatre., Design: Retrospective and prospective cohort study., Setting: South-East Asia., Population: Women with suspicious ovarian cysts., Methods: Proteomic, immunohistochemical and ELISA methods measured haptoglobin in OCF to differentiate benign and EOCs. Diagnostic performance of haptoglobin was compared with CA125, risk malignancy indices (RMI) and frozen section. Blinded validation of the IVDPCT was performed., Main Outcome Measures: Prediction of malignancy., Results: Haptoglobin concentration measured by ELISA was 0.70 ± 0.09 mg/ml in patients with benign cysts (n = 87), 6.22 ± 0.53 mg/ml in early stage-EOC (n = 17), and 6.57 ± 0.65 mg/ml in late stage-EOC (n = 20). Haptoglobin in EOCs was significantly higher than in benign cysts (P < 0.0001). Haptoglobin using rapid colorimetric assay (RCA) on a training set had a sensitivity of 97.3% and a specificity 92.0%, comparable to ELISA and frozen sections. The haptoglobin AUROC curve was 0.999 (95% CI 0.997-1.000) compared with 0.895 (95% CI 0.814-0.977, P < 0.05) for CA125. Haptoglobin performed significantly better than all the RMIs (P < 0.01). Blinded validation studies showed a minor drop in average diagnostic performance (sensitivity 85.2% and specificity 90.5%) compared with the training set. However, when compared with frozen section, haptoglobin was no worse in diagnostic accuracy for malignancy., Conclusion: Haptoglobin was identified as a biomarker for the detection of EOC with potential as a point-of-care diagnostic tool., Tweetable Abstract: Haptoglobin within ovarian cyst fluid: a biomarker for epithelial ovarian cancer and point-of-care diagnostics., (© 2017 Royal College of Obstetricians and Gynaecologists.)

Aims: Harvesting of unfixed tissue from radical prostatectomy specimens for research purposes is challenging. Many prostate cancers cannot be identified at gross inspection, and this tumour is notoriously multifocal and heterogeneous. We aimed to develop a technique to allow detailed topographic analysis and the sampling of a sufficient amount of tumour without jeopardising clinical reporting., Methods and Results: A custom-made double-bladed knife was utilised for cutting a 4-mm-thick horizontal section of the prostate. The slices were split into segments that were frozen in gel, cryosections were cut, and RNA integrity numbers (RINs) were analysed. Sections were cut from all blocks of 20 cases, and the cutting time was monitored. Slides were scanned, and the slices were digitally reconstructed. Cutting frozen sections of an entire slice took 79-253 min (mean 162 min). Tumour was detected in frozen sections of 85% (17/20) of cases and in 46% (72/155) of blocks. The morphological quality was determined to be excellent, and RIN values were high (mean 8.9)., Conclusions: This novel protocol for biobanking of fresh tissue from prostatectomy specimens provides sufficient tumour material for research purposes, while also enabling reporting of histopathology. The harvesting of a full tissue slice facilitates studies of tumour multifocality and heterogeneity., (© 2017 John Wiley & Sons Ltd.)

Background: Recurrence of inverted papilloma (IP) is a problem in 12-17% of tumors. Controversy exists regarding benefits of intraoperative frozen section histopathology (IFSH) for IP resection; however, to our knowledge, no study has specifically investigated this. IFSH for IP resection is the standard of care in our practice. We, therefore, reviewed our outcomes of using IFSH for IP resection. A secondary goal was to assess the reliability of IFSH., Methods: Patients with IP who underwent surgical resection (2010-2016) with minimum 9-month follow-up were included., Results: Twenty-two adults with IP met inclusion criteria. All underwent surgery via endoscopic techniques, supplemented by external ports in five patients. At the time of presentation, 36% IPs were recurrent tumors; 68% were graded as Krouse stage 3. Resection was conducted until "clear" (negative) mucosal margins were achieved on IFSH. In 6 (27%), a "positive" IFSH result dictated additional resection to clear margins. Final negative margins were achieved in all the patients. Both positive and negative predictive values for IFSH were 100% (concordance with final pathology results). Surveillance was performed every 1-6 months with nasal endoscopy by using imaging when necessary. No recurrences were noted (0%) at mean follow-up of 40 months (range, 10-73 months)., Conclusions: Positive IFSH results led to increased resection in 27% of the patients, with a 0% recurrence rate in this cohort. The reliability of IFSH for IP is very high. No recurrence of IP was noted in any patient at a mean follow-up of 3.3 years. IFSH may help reduce recurrence rates of IP, but additional studies with longer follow-up are warranted.

Background: Basal cell carcinomas (BCCs) excised leaving positive tumour margins, are at a higher risk of recurrence. Accordingly, complete tumour removal with preservation of healthy tissue, aiming for low recurrence rates, is the main goal in treating BCCs., Objective: The present study aimed to identify the reliability of the Whole Specimen Intraoperative Frozen Section Analysis (WIFSA) technique by comparing intraoperative WIFSA and postoperative Formalin-Fixed Paraffin-Embedded section analysis (FFPE) results in 1082 basal cell carcinomas and by assessing the recurrence rates during a follow-up period up to 10 years., Methods: A single-centre retrospective cohort of all patients with BCC of the face receiving surgical excision with the WIFSA method between January 2007 and December 2013 was evaluated. We compared the intraoperative frozen section results with postoperative FFPE in order to assess accuracy of the WIFSA. Recurrence rates were assessed among all BCCs with a tumour-free margin at final excision that had a minimum follow-up of 6 months., Results: A total of 996 patients with 1082 BCCs were treated with the WIFSA. Overall agreement of WIFSA with conventional postoperative FFPE was 98·8%, sensitivity and specificity being 99·0% and 98·7% respectively. We excluded 23 BCCs that still had positive tumour margins at the end of the procedure and another 67 for the analysis of recurrence rate because follow-up was shorter than 6 months. A total of 992 BCCs with a tumour-free margin at final excision had a mean follow-up of 5·6 years (mean 67 ± 27·7 months (range 6-117 months)). The total recurrence rate was 2·1% (21 out of 992 BCCs). The recurrence rate among the primary tumours was 1·6% (13 out of 828 cases) and 4·9% among the recurring tumours (8 out of 164 cases)., Conclusion: This study indicates that, in patients with primary or recurring BCCs, WIFSA provides a high accuracy for intraoperative specimen analysis and has a low recurrence rate after a mean follow-up of 5·6 years., Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors., (Copyright © 2017 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.)

The heterogeneity present in solid tumors adds significant difficulty to scientific analysis and improved understanding. Fundamentally, solid tumor formation consists of cancer cells proper along with stromal elements. The burgeoning malignant process is dependent upon modified stromal elements. Collectively, the stroma forms an essential microenvironment, which is indispensable for the survival and growth of the malignant neoplasm. This cellular heterogeneity makes molecular profiling of solid tumors via mass spectrometry (MS)-based proteomics a daunting task. Laser capture microdissection (LCM) is commonly used to obtain distinct histological cell types (e.g., tumor parenchymal cells, stromal cells) from tumor tissue and attempt to address the tumor heterogeneity interference with downstream liquid chromatography (LC) MS analysis. To provide optimal LC-MS analysis of micro-scale and/or nano-scale tissue sections, we modified and optimized a silver-stained one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1D-SDS-PAGE) protocol for the LC-MS analysis of LCM-procured fresh-frozen tissue specimens. Presented is a detailed in-gel digestion protocol adjusted specifically to maximize the proteome coverage of amount-limited LCM samples, and facilitate in-depth molecular profiling. Following LCM, targeted tissue sections are further fractionated using silver-stained 1D-SDS-PAGE to resolve and visualize tissue proteins prior to in-gel digestion and subsequent LC-MS analysis.

Introduction: Inguinal lymph node dissection is an integral part in the management of invasive penile tumors with intraoperative assessment often aiding decision-making during dissection. In this study, we evaluate the diagnostic value of intraoperative frozen section (FS) and analyze clinicopathologic factors that affect its accuracy., Material and Methods: We, retrospectively, reviewed 84 patients with squamous cell carcinoma of the penis who underwent inguinal lymph node dissection at our institution. Intraoperative FS from the superficial inguinal nodes was available in 65 patients and compared with correspondent permanent sections (pathologic node staging [pN]). Sensitivity and specificity were calculated and factors associated with a false negative event were analyzed using logistic regression., Results: The total positive node rate was 60% (39/65). Of 39 pN+ cases, 10 (25.6%) had false-negative FS, whereas the remaining 29 were concordant intraoperatively. Sensitivity and specificity were 0.74 and 1, respectively. On univariable analysis, higher body mass index was associated with a false negative event although there was no association with age, receipt of neoadjuvant therapy, or clinical node stage., Conclusion: Intraoperative FS is highly specific and moderately sensitive for the detection of positive superficial inguinal lymph nodes in penile cancer. Its use can help guide intraoperative surgical planning while limiting its reliance for patients with higher body mass index., (Copyright © 2018. Published by Elsevier Inc.)

Background and Objectives: Trachelectomy, a fertility-sparing surgery for early-stage cervical cancer, can be performed only when there is no extrauterine extension present. Therefore, identifying the sentinel lymph nodes (SLNs) and using them to obtain an intraoperative pathologic diagnosis can provide information on the feasibility and safety of trachelectomy. Our aim was to assess the value of an intraoperative SLN diagnosis., Methods: We retrospectively analyzed the accuracy of intraoperative imprint cytology and frozen-section examination in 201 patients at our institution in whom trachelectomy was planned., Results: All patients could be evaluated for SLNs; a total of 610 SLNs were analyzed. Although the specificity of both imprint cytology and frozen-section examination was 100.0%, the sensitivity was only 58.6 and 65.5%, respectively. The diagnostic sensitivity was higher in 2-mm slices along the short axis than on bisection along the longitudinal axis. Imprint cytology correctly diagnosed 2 patients who had false-negative results on frozen section. The nature of the metastatic foci that caused an intraoperative false-negative diagnosis was either micrometastasis or isolated tumor cells., Conclusions: The accuracy of intraoperative SLN diagnosis requires improvement, especially when small metastatic foci are present., (© 2017 S. Karger AG, Basel.)

Laser Capture Microdissection has earned a permanent place among modern techniques connecting histology and molecular biology. Laser Capture Microdissection has become an invaluable tool in medical research as a means for collection of specific cell populations isolated from their environment. Such genomic sample enrichment dramatically increases the sensitivity and precision of downstream molecular assays used for biomarker discovery, monitoring disease onset and progression, and in the development of personalized medicine. The diversity of research targets (cancerous and precancerous lesions in clinical and animal research, cell pellets, rodent embryos, frozen tissues, archival repository slides, etc.) and scientific objectives present a challenge in establishing standard protocols for Laser Capture Microdissection. In the present chapter, we share our experiences in design and successful execution of numerous diverse microdissection projects, and provide considerations to be taken into account in planning a microdissection study. Our workflow and protocols are standardized for a wide range of animal and human tissues and adapted to downstream analysis platforms.