Targeted RNA Sequencing Highlights a Diverse Genomic and Morphologic Landscape in Low-grade Endometrial Stromal Sarcoma, Including Novel Fusion Genes.

Low-grade endometrial stromal sarcoma (LGESS) represents a morphologically and genetically heterogenous mesenchymal neoplasm. Previous work has shown that approximately half of LGESS are characterized by JAZF1::SUZ12 gene fusions, while a smaller proportion involves rearrangement of other genes. However, a subset of cases has no known genetic abnormalities. To better characterize the genomic landscape of LGESS, we interrogated a cohort with targeted RNA sequencing (RNA-Seq). Cases previously diagnosed as low-grade endometrial stromal neoplasia (n=51) were identified and re-reviewed for morphology and subjected to RNA-Seq, of which 47 were successfully sequenced. The median patient age was 49 years (range: 19 to 85). The most commonly detected fusions were JAZF1::SUZ12 (n=26, 55%) and BRD8::PHF1 (n=3, 6%). In addition to the usual/typical LGESS morphology, some JAZF1::SUZ12 fusion tumors showed other morphologies, including fibrous, smooth muscle, sex-cord differentiation, and myxoid change. Novel translocations were identified in 2 cases: MEAF6::PTGR2 and HCFC1::PHF1 . Ten tumors (21%) had no identifiable fusion, despite a similar morphology and immunophenotype to fusion-positive cases. This suggests that a subset of cases may be attributable to fusion products among genes that are not covered by the assay, or perhaps altogether different molecular mechanisms. In all, these findings confirm that RNA-Seq is a potentially useful ancillary test in the diagnosis of endometrial stromal neoplasms and highlight their diverse morphology.

Comprehensive molecular assessment of mismatch repair deficiency in Lynch associated ovarian cancers using next generation sequencing panel.

OBJECTIVES: Abnormalities in mismatch repair have been described in ovarian cancer, but few studies have examined the causes of mismatch repair deficiency (MMRd). To address this, we completed targeted mutational and methylation sequencing on MMRd ovarian cancer cases. The objective of this study was to explore the molecular mechanism of MMRd using our targeted next generation sequencing panel. METHODS: Newly diagnosed non-serous/mucinous ovarian cancers (n=215) were prospectively recruited from three cancer centers in Ontario, Canada, between 2015 and 2018. Tumors were reflexively assessed for mismatch repair protein by immunohistochemistry. Matched tumor-normal MMRd cases were analyzed on a custom next generation sequencing panel to identify germline and somatic mutations, copy number variants, rearrangements, and promoter methylation in mismatch repair and associated genes. RESULTS: Of 215 cases, 28 (13%) were MMRd. The MMRd cohort had a median age of 52.3 years (range 33.6-62.2), with mostly stage I (50%) and grade 1 or 2 endometrioid histotype (57%). Of the 28 cases, 22 were available for molecular analysis, and Lynch syndrome was detected in 50% of MMRd cases (11/22; seven ovarian cancer and four synchronous ovarian and endometrial cancer: seven MSH6, two MLH1, one PMS2, and one MSH2). An explanation for the observed mismatch repair phenotype was available for 22/22 deficient cases, including 12 MLH1/PMS2 deficient (nine somatic methylation, one bi-allelic somatic deletion, and two pathogenic germline variant), one PMS2 deficient (one pathogenic germline variant), seven MSH6 deficient (seven pathogenic germline variant), and two MSH2/MSH6 deficient (one pathogenic germline variant and one bi-allelic somatic mutation). Concordance between clinical germline testing and panel sequencing results was 100%. CONCLUSIONS: Use of our custom next generation sequencing panel allowed for the streamlined assessment of hereditary and somatic causes of MMRd in ovarian cancers.

Diagnostic accuracy of frozen section and patterns of nodal spread in high grade endometrial cancer: A secondary outcome of the SENTOR prospective cohort study.

OBJECTIVES: The study aimed to define the accuracy of intraoperative frozen section (FS) for the detection of metastases in sentinel lymph node biopsy (SLNB) and describe the pattern of lymph node (LN) spread and relation to molecular classifiers in patients with high-grade endometrial cancer (EC). METHODS: We performed a secondary outcome of clinicopathologic data from the Sentinel Lymph Node Biopsy versus Lymphadenectomy for Intermediate- and High-Grade Endometrial Cancer Staging (SENTOR) prospective cohort study evaluating SLNB in patients with clinical stage I high-grade EC (ClinicalTrials.gov ID: NCT01886066). The primary outcome was the sensitivity of FS of the sentinel lymph node (SLN) specimen, compared to a standardized ultrastaging protocol. Secondary outcomes included the pattern and characteristics of LN spread. RESULTS: There were 126 patients with high-grade EC with a median age of 66 years (range:44-86) and a median Body Mass Index (BMI) of 26.9 kg/m2 (range:17.6-49.3). FS was performed on surgical specimens from 212 hemipelves; SLNs were identified in 202 specimens (95.7%) and fatty tissue alone was identified in 10 specimens (4.7%). Of the 202 hemipelves in which SLNs were identified, 24 were positive for metastatic disease on final pathology. Initial FS correctly identified only 12, yielding a sensitivity of 50% (12/24, 95% CI 29.6-70.4) and a negative predictive value of 94% (178/190, 95% CI 89-96.5). A total of 24 patients (19%) had LN metastases: 16 (13%) had isolated pelvic metastases, 7 (6%) had both pelvic and para-aortic metastases and 1 (0.8%) had an isolated para-aortic metastasis. CONCLUSIONS: Intraoperative FS of SLNs in high-grade EC patients has poor sensitivity. Since isolated para-aortic metastases are rare, para-aortic lymphadenectomy may be omitted in patients in which SLNs were successfully mapped to the pelvis.

Brief family history questionnaire to screen for Lynch syndrome in women with newly diagnosed non-serous, non-mucinous ovarian cancers.

OBJECTIVES: While ovarian cancer is the third most common Lynch syndrome-associated cancer in women, there is no established screening strategy to identify Lynch syndrome in this population. The objective of this study was to assess whether the 4-item brief Family History Questionnaire can be used as a screening tool to identify women with ovarian cancer at risk of Lynch syndrome. METHODS: In this prospective cohort study, participants with newly diagnosed non-serous, non-mucinous ovarian cancer completed the brief Family History Questionnaire, extended Family History Questionnaire, and had tumors assessed with immunohistochemistry for mismatch repair proteins, MLH1 methylation, and microsatellite instability testing. All underwent universal germline testing for Lynch syndrome. Performance characteristics were compared between the brief Family History Questionnaire, extended Family History Questionnaire, immunohistochemistry±MLH1 methylation, and microsatellite instability testing. RESULTS: Of 215 participants, 169 (79%) were evaluable with both the brief Family History Questionnaire and germline mutation status; 12 of these 169 were confirmed to have Lynch syndrome (7%). 10 of 12 patients (83%) with Lynch syndrome were correctly identified by the brief Family History Questionnaire, compared with 6 of 11 (55%) by the extended Family History Questionnaire, 11 of 13 (85%) by immunohistochemistry±MLH1 methylation, and 9 of 11 (82%) by microsatellite instability testing. The sensitivity, specificity, positive predictive values, and negative predictive values of the brief Family History Questionnaire were 83%, 65%, 15%, and 98%, respectively. A combined approach with immunohistochemistry and the brief Family History Questionnaire correctly identified all 12 patients with Lynch syndrome. The brief Family History Questionnaire was more sensitive than the extended Family History Questionnaire and took <10 min for each patient to complete. CONCLUSIONS: The brief Family History Questionnaire alone or combined with immunohistochemistry may serve as an adequate screening strategy, especially in centers without access to universal tumor testing.

Maximizing cancer prevention through genetic navigation for Lynch syndrome detection in women with newly diagnosed endometrial and nonserous/nonmucinous epithelial ovarian cancer.

BACKGROUND: Despite recommendations for reflex immunohistochemistry (IHC) for mismatch repair (MMR) proteins to identify Lynch syndrome (LS), the uptake of genetic assessment by those who meet referral criteria is low. The authors implemented a comprehensive genetic navigation program to increase the uptake of genetic testing for LS in patients with endometrial cancer (EC) or nonserous/nonmucinous ovarian cancer (OC). METHODS: Participants with newly diagnosed EC or OC were prospectively recruited from 3 cancer centers in Ontario, Canada. Family history questionnaires were used to assess LS-specific family history. Reflex IHC for MMR proteins was performed with the inclusion of clinical directives in pathology reports. A trained genetic navigator initiated a genetic referral on behalf of the treating physician and facilitated genetic referrals to the closest genetics center. RESULTS: A total of 841 participants (642 with EC, 172 with OC, and 27 with synchronous EC/OC) consented to the study; 194 (23%) were MMR-deficient by IHC. Overall, 170 women (20%) were eligible for a genetic assessment for LS: 35 on the basis of their family history alone, 24 on the basis of their family history and IHC, 82 on the basis of IHC alone, and 29 on the basis of clinical discretion. After adjustments for participants who died (n = 6), 149 of 164 patients (91%) completed a genetic assessment, and 111 were offered and completed genetic testing. Thirty-four women (4.0% of the total cohort and 30.6% of those with genetic testing) were diagnosed with LS: 5 with mutL homolog 1 (MLH1), 9 with mutS homolog 2 (MSH2), 15 with mutS homolog 6 (MSH6), and 5 with PMS2. CONCLUSIONS: The introduction of a navigated genetic program resulted in a high rate of genetic assessment (>90%) in patients with gynecologic cancer at risk for LS.

Understanding the clinical implication of mismatch repair deficiency in endometrioid endometrial cancer through a prospective study.

OBJECTIVES: Findings on impact of mismatch repair deficiency (MMRd) on patient outcomes in endometrial cancer (EC) have been inconsistent to date. The objective of this study was to compare the oncologic outcomes and recurrence patterns between MMRd and MMR-intact (MMRi) endometrioid EC (EEC). METHODS: Between 2015 and 2018, we prospectively recruited 492 EEC cases from three cancer centers in Ontario, Canada. Tumors were reflexively assessed for MMR protein expression by immunohistochemistry (IHC). Clinicopathological, survival and recurrence patterns were compared between MMRd and MMRi cases. RESULTS: Of 492 EEC, 348 were MMRi (71%) and 144 were MMRd (29%) with median follow-up of 16.8 months (0-69.6). MMRd tumors tended to be grade 2 or 3 (56% vs. 29%, p < 0.001), with propensity for lymphovascular space invasion (28% vs. 18%, p = 0.024), lymph node involvement (7% vs. 5%, p < 0.001) and received more adjuvant treatment (46% vs. 33%, p = 0.027). This group also had significantly lower 3-year recurrence-free survival (78% vs. 90%, p = 0.014) although there was no difference in OS (p = 0.603). MMRd cases were more likely to recur in retroperitoneal lymph nodes (p = 0.045). Upon subgroup analysis, MLH1 methylated tumors had the worst prognostic features and survival outcomes. CONCLUSIONS: MLH1 methylated EECs exhibit more aggressive features compared to other MMRd and MMRi EECs. This may indicate an inherent difference in tumor biology, suggesting the importance of individualized management based on EC molecular phenotype.

Assessment of Sentinel Lymph Node Biopsy vs Lymphadenectomy for Intermediate- and High-Grade Endometrial Cancer Staging.

Importance: Whether sentinel lymph node biopsy (SLNB) can replace lymphadenectomy for surgical staging in patients with high-grade endometrial cancer (EC) is unclear. Objective: To examine the diagnostic accuracy of, performance characteristics of, and morbidity associated with SLNB using indocyanine green in patients with intermediate- and high-grade EC. Design, Setting, and Participants: In this prospective, multicenter cohort study (Sentinel Lymph Node Biopsy vs Lymphadenectomy for Intermediate- and High-Grade Endometrial Cancer Staging [SENTOR] study), accrual occurred from July 1, 2015, to June 30, 2019, with early stoppage because of prespecified accuracy criteria. The study included patients with clinical stage I grade 2 endometrioid or high-grade EC scheduled to undergo laparoscopic or robotic hysterectomy with an intent to complete staging at 3 designated cancer centers in Toronto, Ontario, Canada. Exposures: All patients underwent SLNB followed by lymphadenectomy as the reference standard. Patients with grade 2 endometrioid EC underwent pelvic lymphadenectomy (PLND) alone, and patients with high-grade EC underwent PLND and para-aortic lymphadenectomy (PALND). Main Outcomes and Measures: The primary outcome was sensitivity of the SLNB algorithm. Secondary outcomes were additional measures of diagnostic accuracy, sentinel lymph node detection rates, and adverse events. Results: The study enrolled 156 patients (median age, 65.5 years; range, 40-86 years; median body mass index [calculated as weight in kilograms divided by height in meters squared], 27.5; range, 17.6-49.3), including 126 with high-grade EC. All patients underwent SLNB and PLND, and 101 patients (80%) with high-grade EC also underwent PALND. Sentinel lymph node detection rates were 97.4% per patient (95% CI, 93.6%-99.3%), 87.5% per hemipelvis (95% CI, 83.3%-91.0%), and 77.6% bilaterally (95% CI, 70.2%-83.8%). Of 27 patients (17%) with nodal metastases, 26 patients were correctly identified by the SLNB algorithm, yielding a sensitivity of 96% (95% CI, 81%-100%), a false-negative rate of 4% (95% CI, 0%-19%), and a negative predictive value of 99% (95% CI, 96%-100%). Only 1 patient (0.6%) was misclassified by the SLNB algorithm. Seven of 27 patients with node-positive cancer (26%) were identified outside traditional PLND boundaries or required immunohistochemistry for diagnosis. Conclusions and Relevance: In this prospective cohort study, SLNB had acceptable diagnostic accuracy for patients with high-grade EC at increased risk of nodal metastases and improved the detection of node-positive cases compared with lymphadenectomy. The findings suggest that SLNB is a viable option for the surgical staging of EC.

Tumor site discordance in mismatch repair deficiency in synchronous endometrial and ovarian cancers.

OBJECTIVES: For synchronous endometrial and ovarian cancers, most centers rely on mismatch repair testing of the endometrial cancer to identify Lynch syndrome, and neglect the ovarian tumor site completely. We examined the mismatch repair immunohistochemistry and microsatellite instability results from the endometrium and ovary to assess discordance between the tumor sites and between tests. METHODS: 30 women with newly diagnosed synchronous endometrial and ovarian cancer were prospectively recruited from three cancer centers in Ontario, Canada. Both tumor sites were assessed for mismatch repair deficiency by immunohistochemistry and microsatellite instability test; discordance in results between tumor sites and discordance between test results at each site was examined. Cases with discordant results had tumors sequenced with a targeted panel in order to reconcile the findings. All women underwent mismatch repair gene germline testing. RESULTS: Of 30 patients, 11 (37%) were mismatch repair deficient or microsatellite instable at either tumor site, with 5 (17%) testing positive for Lynch syndrome. Mismatch repair immunohistochemistry expression was discordant between endometrial and ovarian tumor sites in 2 of 27 patients (7%) while microsatellite instability results were discordant in 2 of 25 patients (8%). Relying on immunohistochemistry or microsatellite instability alone on the endometrial tumor would have missed one and three cases of Lynch syndrome, respectively. One patient with Lynch syndrome with a PMS2 pathogenic variant was not detected by either immunohistochemistry or microsatellite instability testing. The rate of discordance between immunohistochemistry and microsatellite instability test was 3.8% in the ovary and 12% in the endometrium. CONCLUSIONS: There was discordance in immunohistochemistry and microsatellite instability results between tumor sites and between tests within each site. Endometrial tumor testing with mismatch repair immunohistochemistry performed well, but missed one case of Lynch syndrome. Given the high incidence of Lynch syndrome (17%), consideration may be given to germline testing in all patients with synchronous endometrial and ovarian cancers.

Performance characteristics of screening strategies to identify Lynch syndrome in women with ovarian cancer.

BACKGROUND: For women with ovarian cancer (OC), the optimal screening strategy to identify Lynch syndrome (LS) has not been determined. In the current study, the authors compared the performance characteristics of various strategies combining mismatch repair (MMR) immunohistochemistry (IHC), microsatellite instability testing (MSI), and family history for the detection of LS. METHODS: Women with nonserous and/or nonmucinous ovarian cancer were recruited prospectively from 3 cancer centers in Ontario, Canada. All underwent germline testing for LS and completed a family history assessment. Tumors were assessed using MMR IHC and MSI. The sensitivity, specificity, and positive and negative predictive values of screening strategies were compared with the gold standard of a germline result. RESULTS: Of 215 women, germline data were available for 189 (88%); 13 women (7%) had pathogenic germline variants with 7 women with mutS homolog 6 (MSH6); 3 women with mutL homolog 1 (MLH1); 2 women with PMS1 homolog 2, mismatch repair system component (PMS2); and 1 woman with mutS homolog 2 (MSH2). A total of 28 women had MMR-deficient tumors (13%); of these, 11 had pathogenic variants (39%). Sequential IHC (with MLH1 promoter methylation analysis on MLH1-deficient tumors) followed by MSI for nonmethylated and/or MMR-intact patients was the most sensitive (92.3%; 95% confidence interval, 64%-99.8%) and specific (97.7%; 95% confidence interval, 94.2%-99.4%) approach, missing 1 case of LS. IHC with MLH1 promoter methylation analysis missed 2 patients of LS. Family history was found to have the lowest sensitivity at 55%. CONCLUSIONS: Sequential IHC (with MLH1 promoter methylation analysis) followed by MSI was found to be most sensitive. However, IHC with MLH1 promoter methylation analysis also performed well and is likely more cost-effective and efficient in the clinical setting. The pretest probability of LS is high in patients with MMR deficiency and warrants universal screening for LS.

Canadian Consensus-based and Evidence-based Guidelines for Benign Endometrial Pathology Reporting in Biopsy Material.

Standardized terminology has proven benefits in cancer reporting; in contrast, reporting of benign diagnoses in endometrial biopsy currently lacks such standardization. Unification and update on the lexicon can provide the structure and consistency needed for optimal patient care and quality assurance purposes. The Special Interest Group in Gynecologic Pathology of the Canadian Association of Pathologists-Association Canadienne des Pathologistes (CAP-ACP) embarked in an initiative to address the current need for consensus terminology in benign endometrial biopsy pathology reporting. Nine members of the Special Interest Group developed a guideline for structured diagnosis of benign endometrial pathology through critical appraisal of the available peer-reviewed literature and joint discussions. The first version of the document was circulated for feedback to a group of professionals in akin fields, the CAP-ACP Executive Committee and the CAP-ACP general membership. The final 1-page document included 17 diagnostic terms comprising the most common benign endometrial entities, as well as explanatory notes for pathologists. The proposed terminology was implemented in the practice of 5 pathologists from the group, who applied the guideline to all benign endometrial biopsies over a 2-wk period. A total of 212 benign endometrial biopsies were evaluated in this implementation step; the recommended terminology adequately covered the diagnosis in 203 cases (95.8%). A list of terminology for benign endometrial biopsy reporting, based on expert consensus and critical appraisal of the available literature, is presented. On the basis of our results of implementation at multiple centers, the proposed guideline can successfully cover the large majority of diagnostic scenarios. The document has the potential to positively impact patient care, promote quality assurance, and facilitate research initiatives aimed at improving histopathologic assessment of benign endometrium.

Endometriosis-associated Ovarian Cancer is a Subset With a More Favorable Outcome and Distinct Clinical-pathologic Characteristics.

There is a controversy about whether endometriosis-associated ovarian cancer (EAOC) might represent a different entity from the corresponding ovarian cancer occurring de novo, in the absence of endometriosis. This study investigated the clinical-pathologic characteristics and outcome of EAOC compared with other ovarian carcinomas that are not associated with endometriosis (non-EAOC) in a large cohort. Seven hundred two patients meeting the inclusion criteria were further subclassified as group I when patients had ovarian carcinoma associated with or arising within endometriosis (EAOC) and group II when patients had non-EAOC. Age, gross features, histologic type, International Federation of Gynecology and Obstetrics stage, and disease-free survival (DFS) were compared between the groups. One hundred sixty-eight (23.9%) patients had EAOC, whereas 534 (76.1%) patients had non-EAOC. EAOCs were mostly endometrioid and clear cell type. Patients with EAOC were younger, present early, and had a lower rate of recurrence when compared with patients with non-EAOC, P<0.001. Patients with EAOC had longer DFS time, 51.9 mo (95% confidence interval, 44.9-58.8) versus 30.5 mo (95% confidence interval, 27.7-33.3) in non-EAOC patients. The 5 yr Kaplan-Meier estimate of DFS rate was 70% in 166 patients of group I and was 39.3% in 532 patients of group II, P<0.001. On multivariate analysis, International Federation of Gynecology and Obstetrics staging, histologic type, and treatment were the only significant factors affecting the hazards of recurrence. Patients with tumors associated with endometriosis are usually, younger, present early, have lower rate of recurrence, longer DFS, and their tumors are of lower grade and are more likely endometrioid or clear cell carcinoma.

Sentinel lymph nodes in vulvar cancer: Management dilemmas in patients with positive nodes and larger tumors.

BACKGROUND: Although sentinel lymph node (SLN) biopsy has been routinely used in the treatment of invasive squamous cell carcinoma (SCC), questions still remain regarding the management of patients with positive nodes, as well as its use in patients with larger tumors. METHODS: Retrospective study of all patients at a single institution with primary vulvar cancer who had SLN biopsy (2008-2015). Patient and tumor characteristics were collected from hospital records. For patients with positive SLN and for those with tumors ≥40 mm, recurrence rates and location were specifically recorded. RESULTS: SLN biopsy was successful in 159 patients (245 groins). Median follow-up was 31 months. 120 patients (187 groins) had a negative SLN without an inguinofemoral lymph node dissection (IFL); there were 6 ipsilateral groin recurrences (5%). 7 patients had micrometastasis (≤2 mm) in the SLN and were treated by radiotherapy. There were no recurrences in the irradiated groins. 19 patients with a positive unilateral SLN had bilateral IFL. One (5.3%) had a positive node in the contralateral groin. 9 patients with positive unilateral SLN had subsequent ipsilateral IFL; there were no groin recurrences in the contralateral groin. 20 patients had tumor size ≥40 mm. 11 patients had a negative SLN biopsy, and thus no IFL; of these patients, 1 had an isolated groin recurrence (9%). CONCLUSION: These data suggest it is reasonable to omit a full groin dissection for micrometastatic disease in the SLN, and to perform a unilateral groin dissection in patients with unilateral SLN metastasis. SLN alone in larger tumors may have a higher groin recurrence rate.

FIGO Versus Silverberg Grading Systems in Ovarian Endometrioid Carcinoma: A Comparative Prognostic Analysis.

The International Federation of Obstetrics and Gynecology (FIGO) grading system for endometrial carcinoma is currently applied to ovarian endometrioid carcinoma (OEC) in many practices. However, previous reports claim superior prognostication by using the Silverberg grading system for ovarian carcinoma. Thus, a thorough comparison between FIGO and Silverberg in OEC is still warranted. A total of 72 OECs diagnosed at our institution were independently graded using both systems. Grade (G) following Silverberg was based on combined scores for architecture, nuclear atypia, and mitotic activity. FIGO grading was based on the % of nonsquamous solid component; severe atypia warranted upgrade to the architectural FIGO grade (G1 to G2 or G2 to G3). Case grouping by grade was correlated with disease-free (DFS), disease-specific (DSS), and overall (OS) survival. Eleven (15.3%) OECs were bilateral, 26 (36.1%) had ovarian surface involvement, and 12 (16.7%) had lymphovascular space invasion. Forty-seven OECs were stage I (65%), 16 (22%) stage II, and 9 (13%) stage III. Median follow-up period was 62 months (range: 1 to 179 mo). Median DFS was 60.5 months (1 to 179 mo); median OS was 61 months (1 to 179 mo). Sixteen (22%) OECs recurred and 9 (13%) patiets died of disease. In univariate analysis, both FIGO and Silverberg correlated significantly with DFS, DSS, and OS (all with P<0.05). However, when compared in multivariate analysis, only Silverberg retained statistical correlation with survival (P<0.05). G1+G2 OEC by Silverberg had significantly better DFS, DSS, and OS compared with G3; such separation was not seen with FIGO. Survival was similar in Silverberg G1 and G2 tumors even 5 years after diagnosis, whereas FIGO G2 tumors had survival approaching G1 in the first 5 years, but declined after the 5-year mark approaching G3 tumors. Tumor laterality, lymphovascular space invasion, and stage also correlated with outcome. Stage showed prognostication superior to all other variables in multivariate analysis. As currently defined, the Silverberg grading system is a better predictor of survival than FIGO. Such differences may be explained by the G2 OEC groups, with G2 Silverberg clustering with G1 tumors, and having a more favorable behavior compared with G2 FIGO. Thus, Silverberg may be preferable in order to stratify patients in low and high-risk categories for prognosis and disease management.

Comprehensive Clinicopathologic and Updated Immunohistochemical Characterization of Primary Ovarian Mucinous Carcinoma.

The distinction of primary mucinous ovarian carcinoma (PMOC) from other primaries or secondaries is essential for selecting therapeutic options and prognostication. We aimed to characterize the immunohistochemical profile of 36 PMOCs using an extended immunohistochemical panel, with clinicopathologic features and outcome. PAX8 was negative in 30 (83.3%), and SATB2 was negative in 32/35. HNF1B, AMACR, and napsin-A were detected in 33 (91.7%), 35 (97.2%), and 0 (0%), respectively. MMR proteins and ARID1A were retained in 100%; PTEN was lost in 4 (11.1%). P53 was aberrant in 10 (27.8%); none overexpressed p16. HER2 was positive in 6/35 (17.1%). Most PMOCs had a favorable outcome. However, recurrence is usually fatal. The typical tumor profile was CK7+, CK20+/-, CDX2+/-, PAX8-, ER-, PgR-, and SATB2-. HER2 positivity suggests a possible target for therapy in advanced disease.

Molecular-based classification algorithm for endometrial carcinoma categorizes ovarian endometrioid carcinoma into prognostically significant groups.

The Cancer Genome Atlas classification divides endometrial carcinoma in biologically distinct groups, and testing for p53, mismatch repair proteins (MMR), and polymerase ɛ (POLE) exonuclease domain mutations has been shown to predict the molecular subgroup and clinical outcome. While abnormalities in these markers have been described in ovarian endometrioid carcinoma, their role in predicting its molecular profile and prognosis is still not fully explored. Patients with ovarian endometrioid carcinomas treated surgically in a 14-year period were selected. Only tumors with confirmation of endometrioid histology and negative WT1 and Napsin-A were included. POLE mutational analysis and immunohistochemistry for p53, MLH1, MSH2, MSH6, and PMS2 was performed in formalin-fixed, paraffin-embedded tissue. Following the molecular classifier proposed for endometrial carcinoma (Br J Cancer2015;113:299-310), cases were classified as POLE mutated, MMR abnormal, p53 abnormal, and p53 wild type. Clinicopathologic information was recorded, including patient outcome. In all, 72 cases were included, distributed as follows: 7 (10%) POLE mutated; 6 (8%) MMR abnormal; 17 (24%) p53 abnormal; and 42 (58%) p53 wild type. The molecular classification correlated with disease-free survival in multivariate analysis (P=0.003), independently of tumor grade and stage. Correlation with overall survival approached statistical significance (P=0.051). POLE-mutated and MMR-abnormal tumors had excellent survival, whereas p53-abnormal tumors had significantly higher rates of recurrence and death. Ovarian endometroid carcinoma can be classified in clinically meaningful subgroups by testing for molecular surrogates, akin to endometrial cancer. MMR and POLE alterations seem to identify a subset of ovarian endometrioid carcinomas with excellent outcome; conversely, abnormal p53 carries a worse prognosis. In the era of personalized medicine, the use of these markers in the routine evaluation of ovarian endometrioid tumors should be considered.

Genomic abnormalities in invasive endocervical adenocarcinoma correlate with pattern of invasion: biologic and clinical implications.

The pattern-based classification system for HPV-related endocervical adenocarcinoma, which classifies tumors based on the destructiveness of stromal invasion, is predictive of the risk of nodal metastases and adverse outcome. Previous studies have demonstrated clinically important molecular alterations in endocervical adenocarcinoma, including KRAS and PIK3CA mutations; however, correlation between the molecular landscape and pathological variables including pattern of invasion has not been thoroughly explored. In this study, 20 endocervical adenocarcinomas were classified using the pattern-based classification system and were subjected to targeted sequencing using the Ion AmpliSeq Cancer Hotspot Panel v2 (ThermoFisher Scientific, Waltham, MA, USA) that surveys hotspot regions of 50 oncogenes and tumor suppressor genes. Single-nucleotide polymorphisms were correlated with clinical and pathologic variables including pattern of invasion. Five (25%), six (30%), and nine (45%) cases were classified as patterns A, B, and C respectively. Lymph node metastases, advanced stage at presentation and mortality from disease were exclusively seen in destructively invasive tumors (patterns B or C). Prevalent mutations in the cohort involved PIK3CA (30%), KRAS (30%), MET (15%), and RB1 (10%). Most (94%) relevant genomic alterations were present in destructively invasive tumors with PIK3CA, KRAS, and RB1 mutations seen exclusively in pattern B or C subgroups. KRAS mutations correlated with advanced stage at presentation (FIGO stage II or higher). Our findings indicate that the pattern of stromal invasion correlates with genomic abnormalities detected by next-generation sequencing, suggesting that tumors without destructive growth (pattern A) are biologically distinct from those with destructive invasion (patterns B and C), and that pattern B endocervical adenocarcinoma is more closely related to its pattern C counterpart. The pattern-based classification may be used as a triage tool when considering molecular testing for prognostic or therapeutic purposes.

Stratified Mucin-Producing Intraepithelial Lesion of the Cervix: Subtle Features Not to Be Missed.

OBJECTIVES: Stratified mucin-producing intraepithelial lesion (SMILE) is an uncommon premalignant lesion of the uterine cervix. A detailed examination of preinvasive SMILE cases including a comparison of the cytologic features with usual-type adenocarcinoma in situ (AIS) and human papillomavirus (HPV) genotyping was performed. STUDY DESIGN: Excisions and preceding Papanicolaou (Pap) tests were retrieved from the files of 2 tertiary care centers. Histologic review estimated the lesional SMILE proportion. Pap tests were reviewed and assessed for architectural, cellular and background features. Cobas® HPV test was performed. RESULTS: 13 cases were identified. Mean/median patient age was 35/33 years (range 23-51 years). Concurrent high-grade squamous intraepithelial lesion was found in 10/13 (77%) and AIS in 8/13 (62%) cases. In 6 cases, SMILE was dominant (≥50%) and represented in 5/6 corresponding Pap tests. Cytology interpretations differed more often in the SMILE-dominant group (p < 0.05). SMILE and AIS had overlapping features. Feathering and prominent nucleoli were absent in SMILE. HPV DNA was detected in all 12 cases tested. HPV 18 was most common (7/12). Excisions with positive/suspicious margins were reported in 5/6 SMILE-dominant versus 3/7 nondominant cases. CONCLUSION: SMILE is best considered as an AIS variant for cytologic, etiologic and management purposes. Cytologic features overlap with AIS, but are more subtle and easily missed. HPV testing may play a role in facilitating SMILE detection.

Ovarian hilar proliferations resembling Sertoli cell tumours: microscopic neoplasms or non-neoplastic remnants?

AIMS: To describe four cases of incidentally detected microscopic ovarian hilar Sertoli cell proliferation, a phenomenon that, as far as we are aware, has not been previously reported, and to discuss the differential diagnosis of these lesions. METHODS AND RESULTS: The proliferations occurred in women aged 35-62 years, and were composed of solid and hollow tubules that were morphologically and immunohistochemically in keeping with Sertoli cells. Two cases were bilateral. CONCLUSIONS: We feel that these uncommon proliferations are likely to represent non-neoplastic embryological remnants rather than hilar Sertoli cell tumours.

Angiosarcoma of the Vulva: A Case Report.

This case illustrates that a very benign looking lesion can be an aggressive cancer. Vulvar lesions need a biopsy to rule out malignancy if they are painful, progressing in size, or changing in appearance.