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Background Endometrial carcinoma represents a sentinel cancer for Lynch syndrome (LS) identification. It is crucial to highlight how other types of tumors can arise in the gynecological tract acting as sentinel tumors in LS patients.Up to now, no established LS patient management strategy has incorporated the presence of these additional candidate sentinel tumors to improve the prevention and management of LS tumors. Methods In order to investigate the involvement of the most frequent gynecological cancers in gynecological cancers, we studied different subsets of gynecological cancers using both somatic approaches, including mismatch repair (MMR) gene immunohistochemical expression, microsatellite instability, and germline analyses ofMSH2, MSH6, MLH1, PMS2 and EPCAM genes.A total of 261 patients referring to the Cancer Genetic Counselling Service of our institution were included in the study. In detail, our series was composed of 131 patients affected by uterus cancers including endometrial, isthmus and non-HPV endocervical carcinomas, 113 patients affected by ovarian cancers and 17 patients affected by synchronous endometrial/ovarian carcinomas (SEOC).In addition, we studied 115 cases of endometrial cancers identified by 2 years of universal testing (endometrial cancers/UTs) using IHC analysis of four MMR proteins. Results and conclusions The incidence of MMR defective gynecological cancers ranged from 7.1 to 47.1% depending on cancer site and selection. LS patients carriers of pathogenetic MMR variants were identified in 19.8% of uterus cancers, 35.3% of SEOC, 4.4% of ovarian cancers. In addition, pathogenetic MMR variants were identified in 4.3% of endometrial cancers/universal testing investigated with universal screening.In conclusion, gynecological cancers are heavily involved in LS and our study shows that MMR screening using immunohistochemical pattern and MSI analysis of endometrial and ovarian cancers as well as of rare entities such as non-HPV related endocervical cancers and synchronous endometrial and ovarian cancers are sentinels for LS.Tumor testing approach improves early identification of MMR defective gynecological cancers and this is an effective strategy to detect high-risk patients and to offer them and their relatives personalized cancer prevention.

Objectives Sinonasal mucosal melanoma (SNMM) is an extremely rare and challenging sinonasal malignancy with a poor prognosis. Standard treatment involves complete surgical resection, but the role of adjuvant therapy remains unclear. Crucially, our understanding of its clinical presentation, course, and optimal treatment remains limited, and few advancements in improving its management have been made in the recent past. Methods We conducted an international multicenter retrospective analysis of 505 SNMM cases from 11 institutions across the United States, United Kingdom, Ireland, and continental Europe. Data on clinical presentation, diagnosis, treatment, and clinical outcomes were assessed. Results One-, three-, and five-year recurrence-free and overall survival were 61.4, 30.6, and 22.0%, and 77.6, 49.2, and 38.3%, respectively. Compared with disease confined to the nasal cavity, sinus involvement confers significantly worse survival; based on this, further stratifying the T3 stage was highly prognostic (p Conclusions We present findings from the largest cohort of SNMM reported to date. We demonstrate the potential utility of further stratifying the T3 stage by sinus involvement and present promising data on the benefit of immune checkpoint inhibitors for recurrent, persistent, or metastatic disease with implications for future clinical trials in this field.

Sinonasal neuroendocrine neoplasms (SN-NENs) are rare and mostly include neuroendocrine carcinoma (NEC), whereas neuroendocrine tumor (NET) is exceptional in this site. Olfactory neuroblastoma (ONB) is a malignant neuroectodermal neoplasm arising in the nasal cavity. Albeit crucial for correct patients’ management, the distinction of high grade ONB from NEC is challenging and requires additional diagnostic markers. The transcription factor SATB2 has been recently introduced in routine diagnostics as an immunohistochemical marker of distal intestine differentiation. No specific data are available about SATB2 and GATA3 expression in SN-NENs. GATA3, SATB2, and, for comparison, CDX2 expression were investigated in a series of epithelial and non-epithelial SN-NENs. We collected 26 cases of ONB and 7 cases of epithelial SN-NENs diagnosed and treated in our Institution. ONBs were graded according to Hyams’ system and epithelial NENs were reclassified into 5 NECs, 1 MiNEN, and 1 amphicrine carcinoma. Immunohistochemistry was performed using standard automated protocols. Hyams’ grades 1–3 ONBs stained diffusely and intensely for SATB2, whereas grade 4 ONBs and NECs were globally negative. The non-neuroendocrine component of MiNEN and the amphicrine carcinoma were strongly positive. GATA3 was heterogeneously and unpredictably expressed in Hyams’ grades 1–3 ONBs, whereas grade 4 ONBs and NECs were completely negative. CDX2 was negative in all cases. Our study identifies, for the first time, SATB2 and GATA3 expression as features of Hyams’ grades 1–3 ONBs, expands the spectrum of SATB2 and GATA3-positive neoplasms, and suggests that Hyams’ grade 4 ONBs are not only clinically but also biologically different from low graded ONBs.

Different risk factors are suspected to be involved in malignant transformation of sinonasal papillomas and include HPV infection, tobacco smoking, occupational exposure, EGFR/KRAS mutations and DNA methylation alterations. In our study, 25 inverted sinonasal papillomas (ISPs), 5 oncocytic sinonasal papillomas (OSP) and 35 squamous cell carcinomas (SCCs) from 54 patients were genotyped for 10 genes involved in EGFR signalling. HPV-DNA detection was performed by in-situ hybridisation and LINE-1 methylation was quantitatively determined by bisulphite-pyrosequencing. High-risk HPV was observed only in 13% of ISP-associated SCC and in 8% of de novo-SCC patients. EGFR mutations occurred in 72% of ISPs, 30% of ISP-associated SCCs and 17% of de novo-SCCs. At 5-year follow-up, SCC arose in only 30% (6/20) of patients with EGFR-mutated ISPs compared to 76% (13/17) of patients with EGFR-wild-type ISP (p = 0.0044). LINE-1 hypomethylation significantly increased from papilloma/early stage SCC to advanced stage SCC (p = 0.03) and was associated with occupational exposure (p = 0.01) and worse prognosis (p = 0.09). In conclusion, our results suggest that a small subset of these tumours could be related to HPV infection; EGFR mutations characterise those ISPs with a lower risk of developing into SCC; LINE-1 hypomethylation is associated with occupational exposure and could identify more aggressive nasal SCC.

Olfactory neuroblastoma (ONB) is a rare sinonasal neoplasm with a peculiar behavior, for which limited prognostic factors are available. Herein, we investigate the transcriptional pathways altered in ONB and correlate them with pathological features and clinical outcomes. We analyze 32 ONB patients treated with curative intent at two independent institutions from 2001 to 2019 for whom there is available pathologic and clinical data. We perform gene expression profiling on primary ONB samples and carry out functional enrichment analysis to investigate the key pathways associated with disease-free survival (DFS). The median age is 53.5 years, all patients undergo surgery and a pure endoscopic approach is adopted in the majority of cases (81.2%). Most patients have advanced disease (stages III–IV, 81.2%) and 84.4% undergo adjuvant (chemo)radiotherapy. The median follow-up is 35 months, 11 (26.8%) patients relapse. Clinical characteristics (gender, stage and Hyams’ grade) are not associated with the outcomes. In contrast, TGF-beta binding, EMT, IFN-alpha response, angiogenesis, IL2-STAT5 and IL6-JAK-STAT3 signaling pathways are enriched in patients experiencing recurrence, and significantly associated with shorter DFS. Clustering of transcriptional profiles according to pathological features indicates two distinct molecular groups, defined by either cytokeratin-positive or -negative immunostaining. Definition of the characterizing ONB transcriptomic pathways may pave the way towards tailored treatment approaches.

Objective: The aim of this study is to assess the association between clinical and radiological features as well as of isocitrate dehydrogenase 1 and 2 (IDH 1,2) mutations with outcome in head and neck chondrosarcomas. Study Design: Retrospective study. Setting: Tertiary referral center. Methods: Clinical, histological, and molecular data of patients with head and neck chondrosarcomas treated by surgery were collected. Results: Forty-six patients were included. The mean age at diagnosis was 56 years (range, 17-78). The tumor originated from the skull base (52.2%), facial bones (28.2%), or laryngotracheal area (19.6%). At last follow-up (median 52.5 months), 38 patients were alive, 30 of which were disease free, whereas 8 had died, 4 of disease progression and 4 of other causes. Fourteen (30.4%) had local recurrence and 2 (4.3%) had lung metastasis. All cases were negative for cytokeratin AE1/AE3, brachyury, and IDH1 at immunohistochemistry, while Sanger sequencing identified IDH1/2 point mutations, typically IDH1 R132C, in 9 (37.5%) tumors arising from the skull base. Margin infiltration on the surgical specimen negatively affected the outcome, whereas no correlation was identified with IDH mutation status. Conclusions: An adequate margin positively affects survival. IDH mutation status does not affect patient outcome.

Characterising the eosinophilic profile represents the main step in chronic rhinosinusitis (CRS) endotyping. The aim of the study is to verify the correlation between different methods for tissue eosinophilia quantification.33 CRS patients undergoing endoscopic sinus surgery and 30 controls undergoing non-CRS surgeries were enrolled. Blood venous sampling, nasal biopsy on uncinate process (UP), nasal cytology on inferior turbinate (IT) and middle meatus (MM) were performed.Differences in eosinophil count in blood (P=0.0001), UP (P#x003C;0.0001), IT (P = 0.01) and MM (P = 0.0006) were significant between CRS cases and controls. A weak correlation was found between UP and blood eosinophil count (r = 0.34, P = 0.006) and between UP and IT eosinophil count (r = 0.30, P = 0.017). Moderate correlation between UP and MM (r = 0.51, P #x003C; 0.0001) was shown. ROC analysis predicted eosinophilic CRS with an overall low sensitivity. Once allergic patients were excluded from the analysis, the sensitivity decreased for sampling on IT and increased for MM sampling.This study suggests that MM cytology gives more accurate information on the degree of tissue eosinophilia. Replication in wide and unbiased cohorts is necessary to verify these results and define accurate thresholds.Il ruolo della citologia nasale nella rinosinusite cronica.L’identificazione del profilo eosinofilico è uno step fondamentale nell’endotipizzazione della rinosinusite cronica (RSC). Lo scopo dello studio è verificare il grado di correlazione tra le diverse metodiche di quantificazione dell’eosinofilia.Sono analizzati, per 33 pazienti RSC candidati a chirurgia endoscopica nasosinusale e 30 controlli sottoposti a chirurgia non RSC-correlata, un campione di sangue venoso periferico, una biopsia del processo uncinato (PU), un citologico sul turbinato inferiore (TI) e un citologico nel meato medio (MM).Differenze tra RSC e controlli negli eosinofili su sangue periferico (P = 0,0001), PU (P #x003C; 0,0001), TI (P = 0,01) e MM (P = 0,0006) sono risultate statisticamente significative. È stata dimostrata una correlazione debole tra sangue periferico e PU (r = 0.34, P = 0,006) e tra PU e IT (r = 0,30, P = 0,017), e una correlazione moderata tra PU e MM (r = 0,51, P #x003C; 0,0001). Le curve ROC hanno predetto forme di RSC eosinofila con una sensibilità globalmente bassa. Escludendo i pazienti allergici la sensibilità si riduce ulteriormente per TI mentre aumenta per MM.Il presente studio suggerisce di eseguire il prelievo citologico nel MM al fine di identificare le RSC eosinofile. Sono necessari studi più ampi per verificare i risultati e definire valori limite adeguati.

OBJECTIVE Outcomes of locally advanced epithelial sinonasal cancers remain unsatisfactory; moreover, only limited and heterogeneous data exist on prognostic factors. METHODS We reviewed all consecutive patients with American Joint Committee Cancer stage III to IV epithelial sinonasal cancers treated with platinum-based induction chemotherapy (IC) followed by locoregional treatment between 1996 and 2015. RESULTS We identified 69 patients treated with a multimodal approach (IC, surgery, radiotherapy). Overall, 44 patients recurred (64%). Of those, 19 patients received salvage surgery, but only four remained disease-free. Median overall survival (OS) was 62.5 months. Sinonasal neuroendocrine and small cell histotypes (P = 0.0085), neuroendocrine differentiation (P = 0.006), and lack of response to IC (P = 0.03) were associated with worse OS. In patients who recurred, median OS was 13 months since recurrence. Survival was longer in patients submitted to salvage surgery (44%) than in those receiving chemotherapy alone at recurrence (29.5 vs. 4.6 months). Patients with a clinical benefit after palliative chemotherapy had a longer median OS than those with disease progression (29.2 vs. 4.4 months; P

Simple Summary Poorly differentiated sinonasal carcinomas (PDSNCs) are rare neoplasms that include a wide spectrum of malignancies characterized by alteration in different epigenetic mechanisms (SWI/SNF complex, IDH2, NUT). The aim of our study was to verify if the identification of specific genetic and epigenetic alterations can be useful to recognize different clinico-pathological subsets of PDSNCs to guide treatment decisions. In our cohort, 14 cases showed alterations in SWI/SNF complex or IDH2 genes, which were associated with a higher global DNA methylation level and worst prognosis. The integration of genetic and epigenetic features appears to be a good strategy to improve the clinico-pathological classification of these tumors and to recognize distinct prognostic entities that deserve tailored clinical management. Abstract Background: Poorly differentiated sinonasal carcinomas (PDSNCs) are rare and aggressive malignancies, which include squamous cell carcinoma (SCC), sinonasal undifferentiated carcinoma (SNUC), and neuroendocrine carcinomas (NEC). Several epigenetic markers have been suggested to support the histopathological classification, predict prognosis, and guide therapeutic decision. Indeed, molecularly distinct subtypes of sinonasal carcinomas, including SMARCB1-INI1 or SMARCA4 deficient sinonasal carcinoma, isocitrate dehydrogenase (IDH)-mutant SNUC, ARID1A mutant PDSNCs, and NUT carcinomas, have recently been proposed as separate entities. Identification of aberrant DNA methylation levels associated with these specific epigenetic driver genes could be useful for prognostic and therapeutic purpose. Methods: Histopathological review and immunohistochemical study was performed on 53 PDSNCs. Molecular analysis included mutational profile by NGS, Sanger sequencing, and MLPA analyses, and global DNA methylation profile using LINE-1 bisulfite-PCR and pyrosequencing analysis. Results: Nine SWI/SNF complex defective cases and five IDH2 p.Arg172x cases were identified. A significant correlation between INI-1 or IDH2 defects and LINE-1 hypermethylation was observed (p = 0.002 and p = 0.032, respectively), which were associated with a worse prognosis (p = 0.007). Conclusions: Genetic and epigenetic characterization of PDSNCs should be performed to identify distinct prognostic entities, which deserved a tailored clinical treatment.

6066 Background: Sinonasal epithelial tumors are rare diseases with several histotypes and poor prognosis. Multimodal approach including surgery is widely used, although no standard therapy has been established in prospective trials. This study assessed activity and safety of an innovative integration of multimodality treatment - IC, surgery and RT - modulated by histology, molecular profile and response to IC. Methods: Pts with untreated, operable squamous cell carcinoma (SCC), p53 wild type intestinal type adenocarcinoma (ITAC), sinonasal undifferentiated and neuroendocrine carcinoma (SNUC, SNEC) were enrolled in a single-arm, phase II, multicenter clinical trial from 2014 to 2018. Pts was treated with up to 5 IC cycles, whose regimen was selected according to histotype, followed either by curative radio-chemotherapy (CRT) (pts with ≥80% reduction of initial tumor volume (TV)) or surgery and adjuvant (C)RT. Photon and/or proton/carbon ion-based RT was employed according to disease site and stage. Primary endpoint was 5 years PFS, secondary endpoints were OS, IC ORR per RECIST 1.1 and safety. Results: Out of 39 enrolled pts, 35 pts were evaluable for primary endpoint. Two pts were only considered for safety analyses because definitive diagnosis on surgical specimen did not meet the study entry criteria; other two pts were screening failure due to inoperable disease. Five-year PFS was 38% (95% CI, 21 – 69), with a median PFS of 26 months. Five-year OS was 46% (95% CI, 28 – 75), with a median OS of 36 months. Responses to IC are reported in table. Globally, 15 pts avoided surgery. Overall treatment safety was in line with multimodality intensive head and neck cancer treatments (5% of pts with G3-4 adverse event during IC). One sudden cardiac death was recorded. At a median follow up of 27 months, 5 G3-4 RT related late adverse events have been recorded (1 G3 neurotoxicity, 2 G3 hearing impairment, 2 G3 xerostomia). Three-year PFS - OS for pts achieving PR/CR vs SD/PD to IC were 49.8% - 56.7% vs 43.2% - 53%, respectively. Conclusions: Treatment of advanced SNC with histology-driven IC followed by locoregional therapy tailored to response to IC was safe and showed survival rate similar to surgery containing case series. In the first prospective study, a surgery sparing multimodal approach proved feasible and effective in IC responsive pts. Clinical trial information: NCT02099175. [Table: see text]

Background The purpose of this study was to report our experience with the endoscopic management of sinonasal schwannomas, analyzing the advantages, limitations, and outcomes of the technique. Methods A retrospective analysis was carried out on 11 patients treated endoscopically between 2000 and 2014 at a single institution. Results Eight patients underwent an exclusive endoscopic endonasal approach, whereas, in 3 patients, an osteoplastic flap was combined because of massive or lateral frontal sinus involvement. The tumor extended into the orbit in 5 cases, and involved the skull base in 5 patients who required a concomitant endoscopic duraplasty. No evidence of disease was observed in 10 patients after a mean follow-up of 90.1 months (range, 14–189 months). One patient was alive with persistence of disease, although asymptomatic. Conclusion The endoscopic endonasal approach is a valid alternative for the vast majority of sinonasal schwannomas with minimal morbidity for the patient. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2074–E2082, 2016

Background Sinonasal mucosal melanoma is a rare malignancy with poor prognosis. Methods Patients with sinonasal malignant melanoma who underwent surgery by different approaches were included in this study. Overall survival (OS) and event-free survival were calculated, and statistically significant variables by univariate analysis were entered in a multivariate Cox regression model. Results Pathological staging was pT3, pT4a, and pT4b in 30 cases (51.7%), 17 cases (29.3%), and 11 cases (19.0%). At 3 and 5 years, OS was 43.5% and 29% and event-free survival was 23.6% and 12.4%, respectively. At univariate analysis, OS was significantly influenced by male sex, advanced pT classification, positive margins, and surgical approach; event-free survival was affected by positive margins. At multivariate analysis, the risk of death was independently associated with male sex (hazard ratio [HR] = 2.27; p = .04) and positive margins (HR = 2.32; p = .03). Conclusion Male sex and positive margins were negative prognostic factors. Endoscopic resection did not show an increased risk of death compared with more extensive surgical approaches. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1737–E1745, 2016

Objective To investigate different treatment strategies for primary early-stage (pT1-T2) sinonasal adenocarcinomas. Methods Retrospective case-control study. From 2000 to 2011, 61 cases were radically resected using an endoscopic endonasal approach. Surgery as a single treatment modality was adopted for 33 patients (study group) while it was followed by postoperative radiotherapy (poRT) in 28 patients (control group). Results Median follow-up was 61 and 67 months for the study and control group respectively. Patients were stratified according to the pT classification and no statistically significant differences were found in terms of Overall (OS) and Recurrence-free (RFS) survival. When analyzing the high-grade tumors (47 cases), statistically significant differences were observed between the control and study groups both in terms of OS (90.5% ± 6.5% versus 57.6% ± 15.4%, P = 0.03) and RFS (92.3% ± 7.39% versus 80.2% ± 8.88%, P = 0.05). Using multivariate analysis, OS was independently determined by poRT (Hazard Ratio = 0.16; P = 0.03) thus confirming its protective role for high-grade adenocarcinomas. Conclusion Our preliminary results suggest that endoscopic endonasal surgery could be used as a single treatment modality for primary early-stage low-grade sinonasal adenocarcinoma, resected with negative margins. Surgery followed by poRT offers the best treatment strategy not only for advanced-stage lesions but also for high-grade adenocarcinomas, regardless of the stage of disease at presentation. J. Surg. Oncol. 2015; 112:561–567. © 2015 Wiley Periodicals, Inc.

Craniopharyngiomas are benign but aggressive epithelial tumors usually originating in the anterior lobe of the pituitary gland from squamous remnants of an incompletely involuted craniopharingeal duct developing from the Rathke pouch. To the authors' knowledge only 1 patient of a primary isolated ethmoidal craniopharyngioma has been reported in the literature.The authors report the case of a 17-year-old boy with a primary extracranial ethmoidal craniopharyngioma. An endoscopic endonasal approach was employed to resect the tumor. After 2 years of clinical and radiological follow-up no recurrence of disease was observed.Primary ethmoidal craniopharyngiomas are rare entities and biopsy is necessary for diagnosis. However, a preoperative assessment by means of nasal endoscopy, computed tomography scan, and enhanced magnetic resonance imaging is mandatory to better evaluate the extension and characteristics of the tumor. The endoscopic endonasal technique is a safe and effective approach for the treatment of these lesions.

Background Intestinal-type adenocarcinoma (ITAC) is a rare and locally aggressive occupation-related tumor. Currently, endoscopic-assisted resection and advances in irradiation modalities (3D conformal radiotherapy/intensity-modulated radiation therapy [IMRT]) are emerging as an alternative to traditional open surgery and conventional radiotherapy. Methods Retrospective analysis of 30 consecutive patients affected with sinonasal ITAC, primarily treated by an endoscopic approach followed by 3D conformal radiotherapy/IMRT at a single institution, from 2003 to 2010. Results The 5-year overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS), and recurrence-free survival (RFS) were 72.7% ± 9.6%, 78% ± 9.5%, 67.9% ± 10.7%, and 69.2% ± 9.4%, respectively (mean follow-up, 48 months). No major complications or serious toxicities were observed. Prognostic factors were stage of disease at diagnosis, development of recurrences, status of surgical margins, grading, tumoral pattern of growth, and proliferative index (Ki-67). Conclusion The low morbidity of endoscopic approaches, the acceptable toxicity of modern irradiation modalities, and these promising survival rates, indicate that this treatment strategy might be considered a safe, minimally invasive, and maximally effective option for treating selected sinonasal ITAC. © 2014 Wiley Periodicals, Inc. Head Neck 37: 677–684, 2015

Ovarian metastases from colorectal carcinoma frequently mimic primary ovarian carcinomas. The present study was performed to identify possible criteria helpful in differential diagnosis. Twenty-three ovarian metastases from colorectal carcinomas and 23 primary ovarian carcinomas were evaluated clinicopathologically and immunostained with antigastric M1 antigen, cathepsin E, CA125, vimentin, estrogen and progesterone receptors, cytokeratins 7 and 20, and alpha-inhibin antibodies. We performed a conventional and molecular cytogenetic study on 5 ovarian metastases from colorectal carcinoma using direct preparation, Q banding techniques, and fluorescence in situ hybridization. Integration of clinicopathologic, immunohistochemical, and cytogenetic features is helpful for the differential diagnosis of metastases of colorectal carcinomas from primary ovarian carcinomas. Bilaterality, extrapelvic spreading, high mitotic index, and cytokeratin 20 immunoreactivity, and lack of M1, CA125, and cytokeratin 7 immunoreactivity favor the diagnosis of ovarian metastases from colon carcinomas. The identification of 13q gain as a peculiar, sensitive, and specific marker of colorectal carcinomas seems relevant.

The first reported case of vaginal serous papillary adenocarcinoma (VSPA) in a 61-year-old woman is presented. The woman had a mass in the upper posterior vaginal wall that was 2.5 cm in maximal dimension and was treated with a radical hysterectomy with bilateral salpingo-oophorectomy, lymphadenectomy, and subtotal vaginectomy, followed by radiation therapy. The ovaries, fallopian tubes, cervix, endometrium, and peritoneum did not show primary or secondary neoplastic involvement. The patient died because of recurrent disease in the form of widespread peritoneal metastases 30 months postoperatively. Microscopically, the tumor was similar to serous papillary adenocarcinoma of the ovary (OSPA). Immunohistochemical studies showed positive staining for CA 125, CA19.9, DUPAN-2, and TAG-72, and negative staining for CEA. Cytogenetic analysis showed chromosome 6 abnormalities similar to those found in OSPA. These results suggest that VSPA is a clinically aggressive primary tumor sharing morphological and cytogenetic analogy with OSPA.

In this report we present the characterization of ovarian neoplasms including benign tumors, borderline tumors, and invasive carcinomas in order to assess whether a sharing of cytogenetic abnormalities is present in all three types of tumors. A cohort of 114 newly diagnosed and untreated ovarian epithelial tumors were analyzed by cytogenetic and molecular cytogenetic approaches with probes specific for chromosome 6. Three groups of chromosome abnormalities were identified: the first group included abnormalities common to all tumor classes (losses of chromosomes 6, 8, 10, 11, 15, 16, 17, 18, 19, 20, 21, 22, and X; gains of chromosomes 1, 3, 5, and 12; 6q24 approximately qter deletions); the second group presented specific abnormalities present in malignant but not in benign tumors (losses of chromosomes 2, 7, 13, and 14; gains of chromosome 4 and chromosome markers); and the last group included abnormalities unique to invasive carcinomas (loss of chromosome 4; gains of chromosomes 2, 7, 8, 9, 10, 16, 17, 18, 19, 20, and 21; 6q16 approximately q24 deletions; rearrangements of 3p, 3q, 13q, and 21q regions). The presence of shared chromosomal alterations in all three types of ovarian neoplasms investigated in this report seems therefore to suggest a progression model for these types of tumors.

This study selected a series of 136 MSI-H (microsatellite instability at high frequency) gastric, colorectal, and endometrial carcinomas combining immunohistochemical analysis for hMLH1 or hMSH2 gene products and microsatellite study. The clinico-pathological profile of all tumours was correlated with the overall instability rates at coding and non-coding repeats, in order to clarify the role and the mutation timing of seven target genes (TGFβRII, IGFIIR, BAX, hMSH3, hMSH6, CHK1, and BRCA2) in the progression of an MSI-H neoplasm. Regardless of the primary site, the results confirm a model of oncogenesis in which inactivation of hMLH1, or less frequently hMSH2, may initiate a pathway culminating in a progressive accumulation of frameshifts in coding region (CDR) microsatellites. Comparing gastrointestinal and endometrial tumours, significantly lower levels of microsatellite instability at both coding and non-coding repeats were observed. Among gastric and colorectal tumours, the detection of small shortening within Bat-26 and Bat-25 markers defines a subgroup of MSI-H gastrointestinal tumours invariably characterized by early stage at diagnosis. In these tumours, mutations of TGFβRII or BAX genes precede frameshifts in the other tested genes. The analysis of correlations between the mutational and clinico-pathological profiles of advanced gastrointestinal tumours revealed that the higher levels of microsatellite instability at both coding and non-coding repeats were not associated with a more advanced clinico-pathological stage or a less favourable outcome. A significant association was observed between a low number of CDR frameshifts and the presence of lymph-node metastasis in advanced gastrointestinal tumours. The existence of advanced MSI-H tumours with more aggressive behaviour and a ‘mild mutator phenotype’ could be explained by hypothesizing an overlapping of different mechanisms of tumourigenesis, including both the mutator and the suppressor pathways; this should be tested by further studies. Copyright © 2002 John Wiley & Sons, Ltd.

Alterations of DNA mismatch repair (MMR) genes are involved in carcinogenesis of sporadic and inherited human cancers characterised by instability of DNA microsatellite sequences (MSI). MSI tumours are usually identified using molecular analysis. In the present investigation, hMLH1 and hMSH2 immunohistochemistry was tested in order to evaluate the utility of this method in predicting MMR deficiency. Colorectal (72), gastric (68), endometrial (44) and ovarian (17) carcinomas were independently evaluated for familial history, histological type of tumour, MSI status and immunohistochemical results. Loss of expression of either hMLH1 or hMSH2 was observed in 51 of 55 (92.8%) MSI tumours, while 145 of 146 microsatellite stable (MSS) tumours expressed both the hMLH1 and hMSH2 gene products. Independently of tumour site, an overall agreement between immunohistochemical and molecular results was observed in 15 hereditary non-polyposis colorectal cancer-related tumours. Among sporadic tumours, only 2 of 60 colorectal and 2 of 66 gastric carcinomas, displaying MSI, expressed both hMLH1 and hMSH2 gene products. All 39 endometrial and 16 ovarian tumours presented a concordant molecular and immunohistochemical profile. These data show that immunohistochemistry is an accurate and rapid method to predict the presence of defective DNA MMR genes and to identify both sporadic and familial MSI tumours.

Fifty-one endometrial cancers were analyzed with regard to whether or how microsatellite instability (MI) was associated with the development of different types of endometrial malignant neoplasms. We investigated 6 loci previously reported as informative for colorectal cancer and a group of 8 loci located on 6q. Replication error (RER+) phenotype was detected in 10 of 51 (19.6%) endometrial cancers (ECs), all but one of which showed endometrioid differentiation. On the contrary, the RER+ phenotype was not detected in serous carcinomas and malignant mixed Müllerian tumors. MI was present in both early and advanced stage ECs. No correlation was found between age, grade, stage, familial pattern, mitotic index, and the RER+ phenotype of ECs. Only 1 of 8 endometrial carcinomas showing MI was associated with mutant p53 expression, while the majority of RER+ tumors were positive for estrogen and progesterone receptors. Our findings suggest that MI plays an early role in endometrial tumorigenesis and is significantly correlated with adenocarcinomas showing endometrioid features (EAs). The frequent involvement of the telomeric region of chromosome 6 in the MI of EA is an indication that this region may be crucial in the process of EA tumorigenesis.