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A primary orbital respiratory cyst is a congenital choristoma that presents in the orbit and with different signs and symptoms depending on the location, which might also change the surgical approach. The aim of this report is to describe 2 new cases of primary respiratory epithelial cysts and to review the literature on presentation, management, and risk factors with different surgical approaches and complications. Two cases presenting with gradually increased proptosis had a confirmed diagnosis of a respiratory epithelial cyst. CT and MRI imaging revealed a thin-walled intraconal cystic lesion. Complete surgical removal was not possible and an incisional biopsy of the wall was performed. Rarely, orbital respiratory epithelium cysts are primary lesions. The high risk of breaking the capsule during surgery and the presence of residual epithelial cells within the orbit may cause cyst's recurrence. Indeed, we recommend careful attention during dissection maneuvers and a long-term follow-up., Competing Interests: The authors have no financial or conflicts of interest to disclose., (Copyright © 2024 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc.)

Purpose: Radioguided surgery (RGS) is a technique that helps the surgeon to achieve a tumour resection as complete as possible, by means of the intraoperative detection of particles emitted by a radiotracer that bounds to tumoural cells. This study aimed to investigate the applicability of β-RGS for tumour resection and margin assessment in cervical cancer patients preoperatively injected with [ 18 F]FDG, by means of Monte Carlo simulations., Methods: Patients were retrospectively included if they had a recurrent or persistent cervical cancer, underwent preoperative PET/CT to exclude distant metastases and received radical surgery. All PET/CT images were analysed extracting tumour SUV max , background SUV mean and tumour-to-non-tumour ratio. These values were used to obtain the expected count rate in a realistic surgical scenario by means of a Monte Carlo simulation of the β probe, assuming the injection of 2 MBq/kg of [ 18 F]FDG 60 min before surgery., Results: Thirty-eight patients were included. A measuring time of ∼2-3 s is expected to be sufficient for discriminating the tumour from background in a given lesion, being this the time the probe has to be over the sample in order to be able to discriminate tumour from healthy tissue with a sensitivity of ∼99% and a specificity of at least 95%., Conclusion: This study presents the first step towards a possible application of our β-RGS technique in cervical cancer. Results suggest that this approach to β-RGS could help surgeons distinguish tumour margins from surrounding healthy tissue, even in a setting of high radiotracer background activity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Background: Aim of the present study was to evaluate the clinical impact of fluorine- 18 F-fluorodeoxyglucose PET/CT ( 18 F-FDG-PET/CT) concurrent with post-therapeutic whole-body radioiodine scan (TxWBS) after first radioiodine (RAI) treatment in patients with high-risk differentiated thyroid carcinoma (DTC)., Methods: This was a retrospective, single-center study including 39 patients with DTC (22 females, 17 males, median age 54; IQR: 35-60 years, 87% papillary thyroid cancer, 13% follicular thyroid cancer). All patients underwent 18 F-FDG-PET/CT and RAI treatment, both performed off L-T4 about 3 months after total thyroidectomy. TxWBS was obtained 3 days afterwards using planar technique and SPECT/CT of neck and thorax regions. Semiquantitative analysis was performed on positive 18 F-FDG-PET/CT scans to assess SUVmax, SUVratio, MTV and TLG values in target lesions (hottest 18 F-FDG-positive lesion present in each patient). Receiver operating characteristics (ROC) curve analysis was obtained to establish a cut-off point for SUVmax able to predict the presence of RAI nonavid lesions. Univariate and multivariate analyses were executed to find out predictive factors for abnormal 18 F-FDG-PET/CT imaging., Results: In 11 (28%) patients 18F-FDG-PET/CT and TxWBS were both negative and in 9 (23%) both positive, showing loco-regional or distant metastases. In 14 patients (36%) 18 F-FDG-PET/CT showed more lesions than TxWBS, while in 5 (13%) patients more lesions were present at TxWBS than 18F-FDG-PET/CT. Overall, 23 patients (59%) showed 18 F-FDG avid lesions and 18 F-FDG-PET/TC changed the management in 14 (36%), including the choice to perform RAI therapy with higher activities than expected, lymph-node dissection for loco-regional metastases, direct therapy for solitary bone metastases. Through ROC curve analysis, a value superior to 7.25 of SUVmax was able to predict the presence of RAI non-avid lesion at TxWBS. Serum stimulated thyroglobulin and extranodal invasion resulted to be risk factors for abnormal 18 F-FDG-PET/CT imaging. However, only extranodal invasion turned out to be an independent risk factor for abnormal 18 F-FDG-PET/CT., Conclusions: The present study demonstrated the clinical value of RAI-concurrent 18 F-FDG-PET/CT in patients with high-risk DTC. However, some questions remain open, including the pretherapeutic thyroglobulin level to use as indication to 18 F-FDG-PET/CT and the predictive value of 18 F-FDG-PET/CT semiquantitative parameters.

Objectives: To evaluate the outcomes of strabismus surgery in patients with thyroid eye disease (TED) and to assess the influence of preceding treatments such as steroid administration, orbital decompression and radiotherapy., Methods: Retrospective study on a cohort of patients with TED undergoing strabismus surgery. Data collection included clinical features, smoking status, preceding steroid therapy, orbital radiation therapy and orbital decompression. Qualitative evaluation, assessing diplopia and quality of life and quantitative evaluation, assessing the eye misalignment were analysed 1 year after the last squint surgical procedure., Results: Seventy-nine patients were identified. Ninety-five surgical procedures were performed on 92 eyes. A significant overall improvement of ocular motility was registered ( p  < 0.001, paired t-test). Forty-five (57%) patients had excellent outcomes, twenty-three (29%) had good outcomes and eleven (14%) had poor outcomes. The average number of muscles operated was significantly greater in patients who underwent orbital bone decompression (1.58 ± 0.63; p  = 0.0082; 95% CI 1.413-10.214). Quantitative and qualitative outcomes were not associated with the preceding therapy: steroid ( p  = 0.75), radiotherapy ( p  = 0.95) or orbital bone decompression ( p  = 0.25). The success rate was no different between adjustable and fixed sutures ( p  = 0.8)., Conclusion: Strabismus surgery in TED patients resulted in a high success rate in reducing diplopia and improving ocular motility. The success rate was not negatively associated with previous therapies. Indeed, resolution of diplopia required more squint procedures in patients who have previously undergone to orbital decompression.

Due to its overexpression on the surface of prostate cancer cells, prostate-specific membrane antigen (PSMA) is a relatively novel effective target for molecular imaging and radioligand therapy (RLT) in prostate cancer. Recent studies reported that PSMA is expressed in the neovasculature of various types of cancer and regulates tumour cell invasion as well as tumour angiogenesis. Several authors explored the role of diagnostic and therapeutic PSMA radioligands in various malignancies. In this narrative review, we describe the current status of the literature on PSMA radioligands' application in solid tumours other than prostate cancer to explore their potential role as diagnostic or therapeutic agents, with particular regard to the relevance of PSMA radioligand uptake as neoangiogenetic biomarker. Hence, a comprehensive review of the literature was performed to find relevant articles on the applications of PSMA radioligands in non-prostate solid tumours. Data on the general, methodological and clinical aspects of all included studies were collected. Forty full-text papers were selected for final review, 8 of which explored PSMA radioligand PET/CT performances in gliomas, 3 in salivary gland malignancies, 6 in thyroid cancer, 2 in breast cancer, 16 in renal cell carcinoma and 5 in hepatocellular carcinoma. In the included studies, PSMA radioligand PET showed promising performance in patients with non-prostate solid tumours. Further studies are needed to better define its potential role in oncological patients management, especially in those undergoing antineoangiogenic therapies, and to assess the efficacy of PSMA-RLT in this clinical context.

Introduction: Pulmonary embolism (PE) can be diagnosed by perfusion lung scintigraphy using human albumin macroaggregates labelled 99m Tc ( 99m Tc-MAA). When PE is suspected, subcutaneous Low Molecular Weight Heparin (LMWH) should be administered even before the results of the PE diagnostic flowchart. In our study, we aimed to evaluate a possible interaction (in vitro interference) between 99m Tc-MAA and LMWH., Methods: The reconstitution of MAA kit was performed according to the manufacturer's instruction. After labelling, we carried out the following preparations: a standard dose of 99m Tc-MAA alone, as control; 99m Tc-MAA and enoxaparin at different ratios. According to the manufacturer's instruction, the radiochemical purity was performed and evaluated immediately (T 0 ), after 15 and 30 minutes after incubation (T 15 and T 30 )., Results: We compared the radiochemical purity of 99m Tc-MAA with: (i) radiochemical purity of 99m Tc-MAA and enoxaparin (11 ratio), (ii) radiochemical purity of 99m Tc-MAA and enoxaparin (0.5 ratio), and (iii) radiochemical purity of 99m Tc-MAA and enoxaparin (ratio 2). No significant differences were found between all the measured parameters at each time point for each ratio. We also tested the stability of 99m Tc-MAA in physiological conditions (at 37°C in PBS): the initial radiochemical purity of 99m Tc-MAA was 99.78%. The values of 99mTc-MAA radiochemical purity were high in all conditions of possible interaction with LMWH, with values ranging from 98.00% at T0 to 95% at T 30 ., Conclusion: We found no statistically significant change in the in vitro stability of 99m Tc-MAA in the presence of enoxaparin, excluding a possible direct interference. Future studies will be needed to check the 99m Tc-MAA stability under physiological conditions., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Purpose: Two new cases of primary cutaneous CD30+ anaplastic large-cell lymphoma (cALCL) of the eyelid are reported; these are analysed alongside existing cases to identify challenges relating to the diagnosis and management of such rare lesions., Material and Methods: A review of existing literature on the PubMed database is conducted using the keywords: 'eyelid lymphoid proliferations', 'lymphoma of the eyelid', and 'primary cutaneous CD30+, ALK-anaplastic large-cell lymphoma of the eyelid'. Two new cases of cALCL are reported. Cases where patients present solely with a nodular periocular lesion are analysed for recurrence and survival rate., Results: Two new patients with a painless ulcerated nodule on the upper eyelid receive a confirmed diagnosis of cALCL after undergoing an excisional biopsy. The first, elderly patient has spontaneous remission; the second patient, with a concomitant chronic infection of hepatitis C virus (HCV), presents a more diffuse disease at the onset and requires radiotherapy. Together with 13 patients a primary cALCL identified from 11 previous studies, this constitutes a cohort of 15 patients. Of these, 10 present with an exclusively nodular lesion of the eyelid and four experience disease recurrence; no deaths from cALCL are reported., Conclusion: Differential diagnosis between primary cALCL and lymphomatoid papulosis is essential and requires careful consideration of clinical and pathologic features. Radiologic staging examination is crucial in order to exclude systemic ALCL, particularly for patients with comorbidity. Though cALCL has the pathological features of a malignant lesion, the prognosis seems favourable for patients; a relatively high percentage even experience spontaneous resolution.

Abstract: A 75-year-old woman had an occasional finding of a left tonsil mass for dysphagia, which resulted a high-grade squamous carcinoma. Therefore, the patient was sent to have a left pharyngectomy. After the pharyngectomy, the patient reported persistent swallowing disorders and nasal reflux. Consequently, she had an oropharyngoesophageal scintigraphy, demonstrating irregular oral and pharyngeal swallowing phases and confirming reflux episodes into the rhinopharynx and into the oropharynx. In line with these findings, the patient was send to rehabilitation; the abnormal functional mechanisms, previously identified by the scintigraphy, allowed to guide the speech therapy, with a progressive clinical improvement., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To investigate the relation between the eighth edition of the American Joint Committee on Cancer staging system and histological risk classification for primary eyelid basal cell carcinoma., Methods: Retrospective, observational case series of patients undergoing excisional biopsy for primary eyelid basal cell carcinoma in two tertiary centres between 2008 and 2018. Patients with <6 months of follow-up were excluded. Outcomes measured included histological subtype, American Joint Committee on Cancer 7 and 8 staging., Results: A total of 222 cases were included over a 10-year period, with a mean (range) follow-up of 25.74 (6-120) months and a median (range) age of 70 (28-93) years. According to American Joint Committee on Cancer 8, the most common T category was T1a (64%), followed by T1b (18%) and T2a (8%). Of the 222 specimens, 183 (82.43%), 17 (7.66%), 19 (8.56%) and 3 (1.35%) were staged as IA, IB, IIA and IIB, respectively. The most common histological subtype was nodular in IA category and infiltrative in categories IB and IIA. Histologically, low-risk basal cell carcinomas were related to lower American Joint Committee on Cancer staging (IA), whereas high-risk basal cell carcinomas were related to American Joint Committee on Cancer stages IB and IIA (p < 0.001). No significant relation was found between T categorisation and risk stratification when adopting American Joint Committee on Cancer 7., Conclusion: American Joint Committee on Cancer 8 staging system is strongly related to primary eyelid basal cell carcinoma histological risk classification.

Aims: The aim of this study is to assess the value of ultrasound in the differential diagnosis of orbital lesions., Methods: One hundred and thirty-eight patients with clinical features of an orbital mass were examined by orbital ultrasound prior to undergoing surgery, from January 2000 to January 2017. All patients underwent excisional or incisional orbital biopsy. The results of orbital ultrasonography were compared with the final histological diagnosis., Results: Orbital lesions were localized by ultrasonography in 133/138 cases (96.4%); the false-negative rate of orbital echography was 3.6% (5/138). The nature of the orbital lesions was correctly determined by ultrasonography in 54.3% of the cases (75/138) preoperatively (true positives). In 58/138 (42%) patients, there was no correspondence between the ultrasound diagnosis and the histological diagnosis (false positives). The sensitivity of orbital ultrasonography for the detection of an orbital mass was 93.75% (CI 87.87-99.63%), while the specificity yielded no meaningful result (CI 0.00-60.24%). Moreover, the specificity of orbital ultrasonography to identify a malignant tumor falls within a CI of 0-62.72%., Conclusions: Orbital ultrasonography is a rapid and noninvasive test that is highly sensitive in displaying an orbital mass; however, the specificity in the differential diagnosis of orbital lesions is not meaningful, particularly if malignancy is suspected. The assessment of orbital diseases requires multiple diagnostic approaches to balance the strengths and weaknesses of each method.

Background: The aim of this study was to analyze patients diagnosed, staged and treated for orbital and eyelid B-cell lymphoma (OEL)., Methods: One hundred and forty-one cases of OEL were included in this study. Primary endpoints were to analyze the histopathologic findings, the main risk factors and the type of treatment and to correlate them with recurrence of OEL. The secondary endpoint was to determine the progression-free survival (PFS) time., Results: Extranodal marginal zone B-cell lymphoma was the most frequent subtype (66%), followed by small lymphocytic lymphoma (12.7%), diffuse large B-cell lymphoma (DLBCL) (9.2%), follicular lymphoma (6.6%), mantle cell lymphoma (4.3%) and Burkitt lymphoma (1.2%). The probability of relapse was influenced by the histopathologic subtype DLBCL (OR = 7.7, 95% CI 1.8-32.3) and treatment with chemotherapy (OR = 14.9, 95% CI 2.6-83.7). Multivariate analysis showed that the histopathologic subtype DLBCL and chemotherapy treatment retained statistical significance for a poorer PFS, with hazard ratios of 8.581 ( p = 0.0112) and 9.239 ( p = 0.0094), respectively., Conclusions: Five lymphoma subtypes were found in patients with OEL. The histopathologic subtype and the type of treatment were found to be the main factors influencing treatment outcome.

Purpose: To compare the binocular visual outcomes and satisfaction of patients with emmetropia or mild myopia (-0.50 diopters [D]) implanted with a bilateral spherical monofocal IOL., Setting: Ophthalmology Department, Humanitas Clinical and Research Center, Rozzano, Milan, Italy., Design: Prospective nonrandomized study., Methods: This study comprised 2 groups of 30 patients each. Group 1 included patients implanted with bilateral monofocal IOLs with near emmetropic target (plano to -0.25 D). Group 2 included patients with a postoperative bilateral target of -0.50 D. Both groups underwent uncorrected and corrected distance defocus curves postoperatively and subjective questionnaires were used to investigate patient satisfaction postoperatively., Results: The defocus curve showed a significant difference between Group 1 and Group 2 binocular vision (all P values <.01 except at -3.00 D where P value = .32) with Group 1 seeing significantly better than Group 2 at +1.00, +0.50, and 0 but significantly worse in all other points of the defocus. In addition, patients of Group 2 at 0 D of defocus curve (infinite) had a visual acuity close to 0 logarithm of the minimum angle of resolution (logMAR) (0.03 ± 0.04). The main outcome of Group 2 defocus curves was that, at defocus point 0 D, even if the mean refraction was -0.67 0.15 × 160, mean uncorrected logMAR visual acuity was 0.0 ± 0.06., Conclusions: Bilateral monofocal IOLs implanted with mild myopic target provided better intermediate visual acuity compared with emmetropia at a minimal cost in terms of uncorrected distance visual acuity.

Background: Solitary fibrous tumors (SFT), formerly called hemangiopericytoma, are rare tumors derived from mesenchymal cells originally described in the pleura, but these tumors may affect extraserosal tissues including the lacrimal gland and orbit., Objective: Conduct a multi-centered clinical, radiological and histopathological analysis of 17 orbital SFT cases., Design: A retrospective case series., Setting: Three eye centers in two countries., Patients and Methods: The data collected from the charts of 17 adult patients presenting with tissue diagnosis of orbital hemangiopericytoma or SFT from January 2003 to December 2018 included demographics, clinical imaging and histopathological information including immunohistochemical (IHC) characteristics., Main Outcome Measures: The demographic characteristics, clinical presentation, and histopathological patterns or variants of SFT were analyzed., Sample Size: 17 adult patients., Results: Mean age was 45 years (range 23-80 years). Male to female ratio was 3:1. The right eye was affected in 12 (70.5%) patients. Commonest presentation was proptosis in 13/17 (76% of patients). Other symptoms were impaired motility (29%) and ptosis (11%). Lesions mostly affected the medial orbit (35%), then orbital apex in 11%. The histopathological classic pattern-less variant was the commonest. One case with aggressive behavior, multiple recurrences and atypical features was encountered. Immunohistochemical (IHC) markers used included CD34 expression in all cases, Bcl-2 expression in 10/11, CD99 in 9/9 and Vimentin in 4/4. STAT6 was used in 2 cases., Conclusions: SFTs are rare tumors affecting the orbit in both genders equally in their mid-forties, but showed male predominance in our analysis with a predominant classic histopathological pattern. Tissue diagnosis is essential and requires IHC studies for confirmation., Limitations: Sample size is relatively small owing to the rarity of this tumor in the orbit., Conflict of Interest: None.

Purpose: The aim of this retrospective study was to determine, by dynamic acquisition, the optimal scan time of F-DOPA PET/CT in patients with recurrent medullary thyroid carcinoma (MTC)., Methods: Twenty-one patients with suspected recurrent MTC underwent dynamic F-DOPA PET/CT (lasting 45 minutes) followed by whole-body scan. Three different time intervals of dynamic acquisition were evaluated: ultra-early phase (2-5 minutes), early phase (5-10 minutes), and late phase (40-45 minutes). The number and SUVmax of all detected lesions among the 3 dynamic acquisition phases were compared on qualitative and semiquantitative analyses. Time-activity curves, SUVmax washout rate between ultra-early or early phase and late phase, and signal-to-noise ratio (SNR) between lesion and background activity were also calculated., Results: At dynamic acquisition, 15 of 21 patients were classified as PET-positive and 6 of 21 as PET-negative, with overall 21 detected lesions. Ultra-early and early imaging provided a better lesion visualization than late phase in more than 70% of cases, as also reflected by SNR (mean SNR reduction between 2 and 45 minutes, -45% ± 19%). Time-activity curves showed a rapid tracer accumulation in MTC lesions, with an average maximum uptake at 2 minutes after injection. Mean lesion SUVmax was 2-fold higher in ultra-early frames compared with last frames (mean washout rate, -44% ± 33%). Finally, compared with whole-body imaging in the same field of view, dynamic acquisition identified 1 additional positive patient and 3 additional lesions in 2 patients., Conclusions: Our study, showing a very fast F-DOPA uptake in MTC lesions, suggests the utility to obtain early PET/CT images, already at 2 to 5 minutes after tracer injection, when maximum lesion tracer uptake is reached.

Background: Metastatic spreading to the lungs is a negative prognostic factor in patients with prostate cancer (PC). Aim of our study was to assess the prevalence of lung PC metastases in patients with fluorine-18 fluoroethyl-choline (F-18-FECh) PET-CT positive lung lesions and the role of Gleason Score (GS) and common biochemical markers in predicting metastatic spreading to the lungs., Methods: We retrospectively evaluated the scans of 1283 patients ongoing (F-18-FECh) PET-CT for PC between May 2010 and July 2014. Patients with lung lesion with F-18-FECh uptake were included. Data concerning GS at diagnosis, "trigger" prostate-specific antigen (PSAtr), PSA doubling time (PSAdt), PSA velocity (PSAvel) and ongoing androgen deprivation therapy were collected. PET-CT findings were confirmed by histology or follow-up (FU) and classified as follows: inflammation, primary lung cancer or metastases from tumor other than PC, and lung metastases from PC., Results: Twenty-two patients with F-18-FECh positive lung lesion and available histology or FU were identified. PSAdt was significantly (P=0.029) shorter in patients with lung metastases from PC (median PSAdt 1.7 months, interquartile range [IQR] 1.5-4.1 months) than in patients without lung PC relapse (median PSAdt 6.7 months, IQR 3.9-7.8); PSAvel was significantly (P=0.019) higher in patients with lung metastases from PC (median PSAvel 3.2 ng/mL/month, IQR 0.65-6.65 ng/mL/month) than in patients without lung PC relapse (median PSAvel 0.3 ng/mL/month, IQR 0.2-0.5 ng/mL/month). Patients with lung metastases from PC had significantly (P=0.006) higher GS at diagnosis (median GS 8) than the other ones (median GS 7)., Conclusions: Our analysis shows that the prevalence of F-18-FECh positive lung metastases in patients with PC, especially with higher GS at diagnosis, is higher in presence of a steady increase in PSA values, confirmed by higher PSAvel and shorter PSAdt.

Aim: Macular pigment density and microvascular density on optical coherence tomography angiography (OCTA) were measured in a cohort of type 1 diabetes mellitus (T1DM) patients with retinopathy in the attempt to shed light on the pathophysiology of this condition., Methods: Eighty-two consecutive eyes of 59 patients with diabetic retinopathy examined at the Eye Clinic of the University of Naples Federico II from November 2016 to April 2017 were enrolled in this prospective study. Eighty normal eyes of 40 age-matched subjects without diabetes mellitus, without a history of glaucoma or evidence of intraocular surgery, and without retinal pathologic features constituted the control group. All patients and controls underwent a complete ophthalmic examination, best corrected visual acuity evaluation according to the ETDRS visual logMAR scale, measurement of intraocular pressure, OCTA, and evaluation of macular pigment., Results: There were no significant age differences between patients and controls. Both macular pigment measurements and vessel density measured by OCTA were significantly lower in patients than in controls. A moderate correlation was found between vessel density in all ETDRS sectors and macular pigment parameters., Conclusions: There was a reduction in macular pigment and in OCTA vessel density in T1DM patients with retinopathy, which may have prognostic value in determining disease progression., (© 2018 S. Karger AG, Basel.)

Introduction: The purpose of this study was to evaluate the potential role of fluorine-18 fluorodeoxyglucose (18F-FDG) positron-emission tomography/computed tomography (PET-CT) in the staging and assessment of chemotherapy response in Ewing sarcoma., Materials and Methods: For 13 patients with Ewing sarcoma, whole-body FDG PET-CT was assessed for site of primary disease, disease extent, and response to therapy. Chest CT, localized magnetic resonance imaging or CT of primary site, and bone scintigrams were evaluated for imaging features of the primary lesion and presence or absence of metastatic disease. Response to therapy was also assessed. Descriptive statistics are reported., Results: Nine patients (69%) presented metastatic disease. All metastatic lung lesions were detected by spiral CT, but some failed to be detected using FDG PET-CT. As regards bone lesions, both FDG PET-CT and bone scans were able to identify bone metastasis, but FDG PET-CT identified more lesions than bone scans. All PET-CT scans at the end of the neoadjuvant chemotherapy showed a decreased FDG uptake., Conclusions: FDG PET-CT seems to be superior to bone scan in the detection of bone metastasis in all districts except skull bones. For pulmonary metastasis smaller than 7 mm, FDG PET-CT is less sensitive than CT. FDG PET-CT may have an important role in initial staging of Ewing sarcoma and subsequent evaluation of response to therapy.

Idiopathic retroperitoneal fibrosis (IRF) is a rare disease characterized by fibro-inflammatory reaction surrounding ureters and other inner organs with possible secondary renal involvement. Symptoms are aspecific and recurrent phases of activity are generally associated with elevation of inflammatory indices. 18F-FDG-PET is nowadays an important tool for the detection of this disease, allowing differentiation between metabolically active tissue and fibrotic one. The purpose of this study was to investigate the role of 18F-FDG-PET in the management of IRF and to evaluate possible correlations between biochemical parameters and PET/CT findings of disease activity. We enrolled seven consecutive patients with IRF (in five histology proved the disease) observed from 2003 to 2012 (5 M:2 F, mean age 53.8 years, range 44-86 years). All patients presented with fever as first symptom; two had obstructive renal failure requiring hemodialysis; one underwent monolateral nephrectomy for parenchyma infiltration; six presented ureteral involvement; three underwent ureteral stent placement. For each patient, during a mean total follow-up of 26.5 months we evaluated serum creatinine, BUN, Hb, RBCs, WBCs, PLT, CRP, ESR. Periodic 18F-FDG-PET/CT scans (every 5.9 months-mean) were performed in all patients. Statistical evaluation was performed using "stepwise regression" analysis. Steroids and immunosuppressive agents induced a progressive normalization of PET/CT scans in all patients at the end of follow-up. Stepwise regression analysis showed that BUN, serum creatinine and CRP only if considered together, significantly correlated with SUV max (p value = 0.000003057). 18F-FDG-PET is a useful tool for clinical decision making in patient with IRF, allowing to evaluate the efficacy of the pharmacological treatment and to detect early recurrences, to modify the therapeutic approach. Acute phase reactants are not reliable alone for the management and the follow-up as they are often not concordant with metabolic assessment of the disease. In patients with ureteral involvement, CRP together with BUN and serum creatinine has a significant correlation with PET/CT results, and can help physicians in therapeutic approach, better than a single parameter.

In diffuse large B-cell lymphoma (DLBCL), the response to first-line immunochemotherapy remains somewhat unpredictable. Interim [(18)F]fluorodeoxyglucose-positron emission tomography (FDG-PET) (PET-int) analysis could be an important tool in the prompt shift to intensified regimens. We prospectively evaluated the effectiveness of PET-int carried out at mid-treatment with standard immunochemotherapy in predicting relapse in a series of 85 consecutive patients with DLBCL. PET-int results were dichotomized as positive or negative using the recently validated five-point scale scoring system. This examination was also compared with interim computed tomography (CT-int) and final PET (PET-fin). End-points were: complete remission (CR), positive predictive value (PPV) of refractoriness and relapse, negative predictive value (NPV), overall survival (OS) and progression-free survival (PFS). Observation time was fixed to 24 months unless preceded by a DLBCL-related event. The PPV of PET-int was 58% and the NPV was 77%. CR was correlated with both PET-int and CT-int (p < 0.0001), but in multivariate analysis only CT-int was correlated with CR (p = 0.002). CT-int and PET-fin were predictive of both OS and PFS, whereas PET-int was predictive only of OS (p = 0.013). In Cox regression only PET-fin was predictive for both OS (p = 0.004) and PFS (p = 0.005). PET-int was unable to discriminate those chemosensitive patients who would later relapse. We therefore believe that the use of this expensive radioactive tool is not justified as an interim analysis.