Tubo-ovarian High-grade Serous Carcinoma Research Articles

Exosome Secretion and Epithelial-Mesenchymal Transition in Ovarian Cancer Are Regulated by Phospholipase D.

Phospholipase D (PLD) isoenzymes participate in a variety of cellular functions that are mostly attributed to phosphatidic acid (PA) synthesis. Dysregulation of PLD regulates tumor progression and metastasis, yet little is known about the underlying mechanism. We previously reported on the expression and clinical role of the PLD isoenzymes PLD1 and PLD2 in tubo-ovarian high-grade serous carcinoma (HGSC). In the present study, we investigated the biological function of PLD1 and PLD2 using the OVCAR-3 and OVCAR-8 HGSC cell lines. KO cell lines for both PLDs were generated using CRISPR/CAS9 technology and assayed for exosome secretion, spheroid formation, migration, invasion and expression of molecules involved in epithelial-mesenchymal transition (EMT) and intracellular signaling. Significant differences between PLD1 and PLD2 KO cells and controls were observed for all the above parameters, supporting an important role for PLD in regulating migration, invasion, metastasis and EMT.

The prognostic value of the chemotherapy response score in tubo-ovarian or primary peritoneal high-grade serous carcinoma (466)

<b>Objectives:</b> The purpose of the study was to evaluate the prognostic value of a two-tiered chemotherapy response score (CRS) system on progression-free and overall survival in high-grade serous ovarian cancer patients using traditional survival type analysis. <b>Methods:</b> Retrospective chart data were collected from all patients aged 18 and older with FIGO stage III or IV tubo-ovarian high-grade serous carcinoma undergoing neoadjuvant chemotherapy (NACT) at a single institution from January 2017 to January 2021. A two-tier scoring system was used in which patients were stratified to either CRS 1-2 (no or minimal response to neoadjuvant chemotherapy) or CRS 3 (appreciable or near-complete response). These data were used to compare progression-free and overall survival between the patients in each subgroup using survival analysis (log-rank test). Survival data were adjusted for covariates as appropriate with a Cox regression model. <b>Results:</b> We identified 80 women who met the inclusion criteria above; 97% (<i>n</i>=78) were Caucasian, and the mean age was 66 years (range: 25-87). Baseline demographic data were similar between patients with CRS 1-2 (<i>n</i>=58) and patients with CRS 3 (<i>n</i>=22). More women with CRS 3 underwent an aborted attempt at cytoreduction or surgery for bowel obstruction at the time of diagnosis (<i>n</i>=3 compared to none in the CRS 1-2 cohort). Overall, 74% (<i>n</i>=58) of patients achieved a partial response on platinum-based NACT. About 23% (<i>n</i>=5) of patients with CRS 3 had a complete response compared to only 12.5% (<i>n</i>=7) of CRS 1-2. Overall a greater percentage of patients in the CRS 3 group (95%, <i>n</i>=21) achieved optimal cytoreduction compared with patients in CRS 1-2 (74%, <i>n</i>=43). <i>BRCA1</i> or <i>2</i> mutation frequencies were similar in both CRS subgroups. The majority of women recurred (73%, <i>n</i>=59) regardless of the CRS subgroup. Ultimately five patients were excluded from the analysis of progression-free and overall survival due to pertinent missing information such as documented CRS or missing vital statistics. The mean time from diagnosis to recurrence was 16 months versus 19 months for CRS 1-2 compared to CRS 3, but this difference was not significant. Median time from interval debulking to recurrence was not different between groups (11 months for CRS 1-2 vs 13 months for CRS 3, p=0.21). There was no difference in overall survival between the two groups; mean survival was 35 months in CRS 1-2 versus 34 months in CRS 3 (p=0.86). <b>Conclusions:</b> Previous studies have suggested a difference in progression-free survival for women who had CRS 1-2 versus CRS 3, indicating that this scoring system can inform disease prognosis and may help to guide adjuvant treatment strategies. Our preliminary analysis revealed no statistically significant difference in progression-free or overall survival for patients with CRS 1-2 versus CRS 3 and did not replicate the findings of other studies, a discrepancy that warrants further investigation.

Prognostic value of regulatory T cells and T helper 17 cells in high grade serous ovarian carcinoma

PurposeIn recent years the tumor microenvironment and its interaction with the tumor has emerged into research focus with increased attention to the composition of Tumor-infiltrating lymphocytes. We wanted to quantify the composition of Regulatory T cells (Tregs) and T helper 17 cells (Th17 cells) and their prognostic impact in high-grade serous tubo-ovarian carcinoma.MethodsTregs and Th17 cells were determined by immunohistochemical analysis of CD25 FoxP3 and RORγt, respectively on tissue microarrays of a cohort of 222 patients with reviewed histology and available clinical data. Expression was analyzed with Qupath for quantification and integration with clinical data enabled calculation of prognostic impact. For validation FOXP3 and RORC mRNA expression levels from 502 patients with HGSC in publicly available datasets were evaluated.ResultsAn average percentage of 0.93 Tregs and of 0.06 Th17 cells was detected per cells in overall tissue. Optimal cut-offs were determined and higher Tregs were associated with a better overall survival in stroma (p = 0.006), tumor area (p = 0.0012) and overall tissue (p = 0.02). After accounting for well-known prognostic factors age at diagnosis, residual tumor and FIGO stage, this association remained significant for stromal Tregs with overall survival (p = 0.02). Survival analysis for Th17 cells revealed no significant association with survival rates. Moreover, lower Th17/Treg ratios had a positive impact on patient overall survival (p = 0.025 tumor, p = 0.049 stroma and p = 0.016 overall tissue).ConclusionOur results outline a positive prognostic effect for higher Tregs but not for Th17 in high grade serous tubo-ovarian carcinoma.

Ovarian carcinosarcoma is a distinct form of ovarian cancer with poorer survival compared to tubo-ovarian high-grade serous carcinoma

BackgroundOvarian carcinosarcoma (OCS) is an uncommon, biphasic and highly aggressive ovarian cancer type, which has received relatively little research attention.MethodsWe curated the largest pathologically confirmed OCS cohort to date, performing detailed histopathological characterisation, analysis of features associated with survival and comparison against high-grade serous ovarian carcinoma (HGSOC).ResultsEighty-two OCS patients were identified; overall survival was poor (median 12.7 months). In all, 79% demonstrated epithelial components of high-grade serous (HGS) type, while 21% were endometrioid. Heterologous elements were common (chondrosarcoma in 32%, rhabdomyosarcoma in 21%, liposarcoma in 2%); chondrosarcoma was more frequent in OCS with endometrioid carcinomatous components. Earlier stage, complete resection and platinum-containing adjuvant chemotherapy were associated with prolonged survival; however, risk of relapse and mortality was high across all patient groups. Histological subclassification did not identify subgroups with distinct survival. Compared to HGSOC, OCS patients were older (P < 0.0001), more likely to be FIGO stage I (P = 0.025), demonstrated lower chemotherapy response rate (P = 0.001) and had significantly poorer survival (P < 0.0001).ConclusionOCS represents a distinct, highly lethal form of ovarian cancer for which new treatment strategies are urgently needed. Histological subclassification does not identify patient subgroups with distinct survival. Aggressive adjuvant chemotherapy should be considered for all cases, including those with early-stage disease.

Aging accelerates while multiparity delays tumorigenesis in mouse models of high-grade serous carcinoma

ObjectivesThe “incessant ovulation” hypothesis links increased risk for tubo-ovarian high-grade serous carcinoma (HGSC) due to more ovulations and reduced risk conferred by pre-menopausal exposures like oral contraceptive use, multiparity, and breastfeeding. However, most women diagnosed with HGSC are postmenopausal, implying age is a major risk factor for HGSC. Our mouse model for HGSC, based on tamoxifen (TAM)-induced somatic inactivation of the Brca1, Trp53, Rb1, and Nf1 (BPRN) tumor suppressor genes in oviductal epithelium, recapitulates key genetic, histopathologic, and biological features of human HGSCs. We aimed to credential the model for future efforts to define biological and risk modification factors in HGSC pathogenesis. MethodsBPRN mice were treated with TAM to induce tumors at defined ages and parity status. ResultsBPRN mice aged 9-months prior to tumor induction had markedly shorter survival than 6–8 week old mice induced to form tumors (median 46.5 weeks versus 61.5 weeks, log-rank test P = 0.0006). No significant differences in cancer phenotypes were observed between multiparous versus nulliparous BPRN mice. However, using a modified tumor model with one wild-type Nf1 allele (BPRNfl/+), nulliparous mice had more advanced tumors than multiparous mice (Mantel-Haenszel Chi-square test of association, P = 0.01). ConclusionsOur findings show aging is associated with significantly shortened survival post tumor induction in the BRPN model and multiparity delays development and/or progression of HGSC in certain genetic contexts. The findings support relevance of our mouse model to gain mechanistic insights into how known factors exert their protective effects and to test novel approaches for HGSC prevention.

MCM3 is a novel proliferation marker associated with longer survival for patients with tubo-ovarian high-grade serous carcinoma.

Tubo-ovarian high-grade serous carcinomas (HGSC) are highly proliferative neoplasms that generally respond well to platinum/taxane chemotherapy. We recently identified minichromosome maintenance complex component 3 (MCM3), which is involved in the initiation of DNA replication and proliferation, as a favorable prognostic marker in HGSC. Our objective was to further validate whether MCM3 mRNA expression and possibly MCM3 protein levels are associated with survival in patients with HGSC. MCM3 mRNA expression was measured using NanoString expression profiling on formalin-fixed and paraffin-embedded tissue (N = 2355 HGSC) and MCM3 protein expression was assessed by immunohistochemistry (N = 522 HGSC) and compared with Ki-67. Kaplan-Meier curves and the Cox proportional hazards model were used to estimate associations with survival. Among chemotherapy-naïve HGSC, higher MCM3 mRNA expression (one standard deviation increase in the score) was associated with longer overall survival (HR = 0.87, 95% CI 0.81-0.92, p < 0.0001, N = 1840) in multivariable analysis. MCM3 mRNA expression was highest in the HGSC C5.PRO molecular subtype, although no interaction was observed between MCM3, survival and molecular subtypes. MCM3 and Ki-67 protein levels were significantly lower after exposure to neoadjuvant chemotherapy compared to chemotherapy-naïve tumors: 37.0% versus 46.4% and 22.9% versus 34.2%, respectively. Among chemotherapy-naïve HGSC, high MCM3 protein levels were also associated with significantly longer disease-specific survival (HR = 0.52, 95% CI 0.36-0.74, p = 0.0003, N = 392) compared to cases with low MCM3 protein levels in multivariable analysis. MCM3 immunohistochemistry is a promising surrogate marker of proliferation in HGSC.

SPL-108 mediates metastasis and chemoresistance in high-grade serous tubo-ovarian carcinoma

Objectives: Overcoming chemoresistance will improve outcomes for all women with tubo-ovarian carcinomas. Mechanisms of chemoresistance are multifactorial and heterogeneous. ABCB1 (MDR1) represents one common resistance mechanism in tubo-ovarian carcinomas and is under the regulation of CD44. In the present study we examined the effects of a novel CD44 modulator, SPL-108, in a panel of ovarian cancer cell lines. Methods: We assessed chemosensitivity and migration effects of SPL-108 in a panel of ovarian cancer cell lines with (OVCAR5, OVCAR8, OVCAR3) and without (OVCAR4, CAOV3) MDR1 expression. In vitro experiments (cell viability assay, Western blot analysis, Calcein AM fluorescence assay, and migration assay) were carried out to determine the functional effects of SPL-108. Results: Higher expression of CD44 was seen in OVCAR5 and OVCAR8 on Western Blot analysis. In transwell migration assay, treatment with SPL-108 decreased the number of migrating cells compared to control in OVCAR8 (mean ± SEM, 149.1 ± 22.8 vs 89.0 ± 16.5 cells, p=0.04), OVCAR5 (177.7 ± 15.4 vs 134.5 ± 14.7 cells, p=0.04) and OVCAR3 (111.2 ± 12.4 vs 50.5 ± 9.4 cells, p Conclusions: SPL-108 treatment has anti-metastatic properties and suppresses chemoresistance in preclinical models of ovarian cancer. Ongoing studies in animal models will help to guide the further clinical development of SPL-108. Download : Download high-res image (262KB) Download : Download full-size image

High-grade serous ovarian tumor cells modulate NK cell function to create an immune-tolerant microenvironment.

SUMMARYTubo-ovarian high-grade serous carcinoma (HGSC) is unresponsive to immune checkpoint blockade despite significant frequencies of exhausted T cells. Here we apply mass cytometry and uncover decidual-like natural killer (dl-NK) cell subpopulations (CD56+CD9+CXCR3+KIR+CD3−CD16−) in newly diagnosed HGSC samples that correlate with both tumor and transitioning epithelial-mesenchymal cell abundance. We show different combinatorial expression patterns of ligands for activating and inhibitory NK receptors within three HGSC tumor compartments: epithelial (E), transitioning epithelial-mesenchymal (EV), and mesenchymal (vimentin expressing [V]), with a more inhibitory ligand phenotype in V cells. In cocultures, NK-92 natural killer cells acquire CD9 from HGSC tumor cells by trogocytosis, resulting in reduced anti-tumor cytokine production and cytotoxicity. Cytotoxicity in these cocultures is restored with a CD9-blocking antibody or CD9 CRISPR knockout, thereby identifying mechanisms of immune suppression in HGSC. CD9 is widely expressed in HGSC tumors and so represents an important new therapeutic target with immediate relevance for NK immunotherapy.

HER2 Protein Overexpression and Gene Amplification in Tubo-Ovarian High-grade Serous Carcinomas.

Most tubo-ovarian high-grade serous carcinomas (TO-HGSC) are diagnosed in advanced stages. Although the majority of patients achieve initial remission with cytoreductive surgery and chemotherapy, mortality rate remains high due to recurrent/progressive disease. The addition of trastuzumab to carboplatin-paclitaxel improved progression-free survival of patients with human epidermal growth factor receptor 2 (HER2)-positive uterine serous carcinoma. After this encouraging result of transtuzumab in HER2-positive uterine serous carcinoma, we aimed to determine the frequency of HER2 overexpression/amplification in TO-HGSC and reveal the utility of 2018 ASCO/CAP HER2 testing guideline in breast cancer for TO-HGSC. For 100 cases, HER2 protein expression was assessed by immunohistochemistry and scored from 0 to 3+ according to 2018 ASCO/CAP HER2 testing guideline. HER2 gene amplification was assessed by florescence in situ hybridization for all the 2+ and 3+ cases as well as 5 of the 0/1+ cases. Among 100 cases, immunohistochemistry scores were 0/1+ in 81 cases, 2+ in 18 cases and 3+ in 1 case. By florescence in situ hybridization, the only 3+ case and 1 of the 2+ cases were HER2-amplified and all 5 of the 0/1+ cases were HER2 nonamplified. Subclonal HER2 overexpression/amplification was identified in 1 of the neoadjuvant cases comprising <10% of the entire tumor. In summary, HER2 overexpression/amplification was found in 2% of TO-HGSC. The 2018 ASCO/CAP HER2 testing guideline in breast cancer can be utilized for TO-HGSC. Future studies are needed to explore HER2-targeted therapies in TO-HGSC and expand the patient population who may benefit from HER2-targeted therapies such as patients with activating mutations in HER2 gene without overexpression/amplification.

Computational modeling of ovarian cancer dynamics suggests optimal strategies for therapy and screening

High-grade serous tubo-ovarian carcinoma (HGSC) is a major cause of cancer-related death. Treatment is not uniform, with some patients undergoing primary debulking surgery followed by chemotherapy (PDS) and others being treated directly with chemotherapy and only having surgery after three to four cycles (NACT). Which strategy is optimal remains controversial. We developed a mathematical framework that simulates hierarchical or stochastic models of tumor initiation and reproduces the clinical course of HGSC. After estimating parameter values, we infer that most patients harbor chemoresistant HGSC cells at diagnosis and that, if the tumor burden is not too large and complete debulking can be achieved, PDS is superior to NACT due to better depletion of resistant cells. We further predict that earlier diagnosis of primary HGSC, followed by complete debulking, could improve survival, but its benefit in relapsed patients is likely to be limited. These predictions are supported by primary clinical data from multiple cohorts. Our results have clear implications for these key issues in HGSC management.

A Keratin 7 and E-Cadherin Signature Is Highly Predictive of Tubo-Ovarian High-Grade Serous Carcinoma Prognosis.

During tubo-ovarian high-grade serous carcinoma (HGSC) progression, tumoral cells undergo phenotypic changes in their epithelial marker profiles, which are essential for dissemination processes. Here, we set out to determine whether standard epithelial markers can predict HGSC patient prognosis. Levels of E-CADH, KRT7, KRT18, KRT19 were quantified in 18 HGSC cell lines by Western blot and in a Discovery cohort tissue microarray (TMA) (n = 101 patients) using immunofluorescence. E-CADH and KRT7 levels were subsequently analyzed in the TMA of the Canadian Ovarian Experimental Unified Resource cohort (COEUR, n = 1158 patients) and in public datasets. Epithelial marker expression was highly variable in HGSC cell lines and tissues. In the Discovery cohort, high levels of KRT7 and KRT19 were associated with an unfavorable prognosis, whereas high E-CADH expression indicated a better outcome. Expression of KRT7 and E-CADH gave a robust combination to predict overall survival (OS, p = 0.004) and progression free survival (PFS, p = 5.5 × 10−4) by Kaplan–Meier analysis. In the COEUR cohort, the E-CADH-KRT7 signature was a strong independent prognostic biomarker (OS, HR = 1.6, p = 2.9 × 10−4; PFS, HR = 1.3, p = 0.008) and predicted a poor patient response to chemotherapy (p = 1.3 × 10−4). Our results identify a combination of two epithelial markers as highly significant indicators of HGSC patient prognosis and treatment response.

Gastrointestinal Stromal Tumors (GISTs) as Incidental Findings in Gynecological Surgery.

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors of the gastrointestinal tract that may be diagnosed incidentally as a part of intra-abdominal surgery for other diseases. This is a single center review to document the incidental finding of GIST at surgery for gynecological malignancies during a 10-yr period. Sixteen cases of incidental GISTs were identified in women ranging in age from 39 to 82 yr. GISTs presented as incidental secondary lesions in women undergoing surgery for other indications, typically primary debulking surgery for tubo-ovarian high-grade serous carcinoma. The GIST was located in the stomach wall in 9 cases. Other sites were cecum, omentum, and mesentery. Diagnosis of GIST was supported by immunohistochemistry in all cases and by molecular studies in 3 cases. Seventy-five percent of cases were micro-GISTs, measuring <2 cm in diameter and, where Miettinen and Lasota criteria could be applied, fitted into "no risk," "very low risk" or "low risk" prognostic groups. Seventy-five percent of women for whom survival data was available, showed disease-free survival at follow-up. The 2 women who died had concurrent high stage or high-grade gynecological malignancy at initial diagnosis.

Immunotyping in tubo-ovarian high-grade serous carcinoma by PD-L1 and CD8+ T-lymphocytes predicts disease-free survival.

PD-L1 immune checkpoint inhibitor expression was evaluated in high-grade serous carcinoma (HGSC) ovary in the context of the overall immune landscape to determine its prognostic value. Consecutive cases of HGSC, 50 who underwent upfront surgery followed by adjuvant chemotherapy (HGSC-U) and 50 who underwent neoadjuvant chemotherapy (NACT) followed by interval debulking surgery (HGSC-PC) were selected. In HGSC-PC cases, the pre-NACT ascitic fluid cell blocks were included. Tumor-infiltrating lymphocytes (TILs) were scored, hotspots chosen for tissue microarray construction and immunohistochemistry performed and scored for CD4 and CD8 lymphocyte subsets, CD68+ tumor-associated macrophages (TAMs), PD-1 and PD-L1 expression. HGSC-post-chemotherapy showed increased TILs, predominantly CD8+T-lymphocytes, compared to HGSC-U. HGSC showed PD-L1 expression on tumor cells and/or TAMs in 60% cases with a linear correlation to CD4+, CD8+ TIL levels. Concordant PD-L1 expression was seen in matched pre- and post-NACT tumor cells. HGSC-PC showed higher expression of PD-L1. There was no association of PD-L1 cumulative proportion score or tumor cell score with outcome. Taking a cutoff for PD-L1 CPS at 10%, immunotype I (PD-L1+/CD-8+), corresponding to tumors with adaptive immune evasion, showed worst disease-free survival compared to all other immunotypes (p=0.03) and was more significant (p=0.01) when compared to immunotype III (PD-L1+/CD8-). Immunotyping based on PD-L1/CD8+ expression correlates to prognosis and outcome.

The added value of CA125 normalization before interval debulking surgery to the chemotherapy response score for the prognostication of ovarian cancer patients receiving neoadjuvant chemotherapy for advanced disease

Objective: To investigate whether CA125 normalization following neoadjuvant chemotherapy (NACT) can complement the chemotherapy response system (CRS) in the prognostication of patients with tubo-ovarian high-grade serous carcinoma (HGSC).Methods: In total, 118 HGSC patients who received NACT followed by interval debulking surgery (IDS) for FIGO stage IIIC-IV disease were included, and their clinical data were retrospectively reviewed. The primary endpoint was progression-free survival (PFS). Cox regression analysis was performed to identify predictors of PFS.Results: Following NACT, CRS3 was noted in 35 patients (29.7%), and CA125 normalization (≤ 35 U/ml) was noted in 54 patients (45.8%). Both CRS3 and CA125 normalization were identified as independent prognosticators of PFS. Combining these two factors, we stratified the 106 patients into three groups with different risks of recurrence: low-risk group (CRS3 + post-NACT CA125≤ 35 U/ml; n = 17, 14.4%), intermediate-risk group (CRS3 + post-NACT CA125 > 35 U/ml; n = 19, 16.1%) and high-risk group (CRS1-2; n= 82, 69.5%). The differences in PFS between the three groups were significant (log-rank test, P < 0.0001). In Cox regression analyses, the new stratification method was found to have an independent prognostic effect.Conclusion: Both the CRS system and the normalization of CA125 following NACT could reliably predict the risk of recurrence following primary treatment. The combination of the two factors refined the prognostic stratification of HGSC patients who were treated with NACT and IDS.

Tumor BRCA Testing in High Grade Serous Carcinoma: Mutation Rates and Optimal Tissue Requirements

Simple SummaryApproximately 25% of women diagnosed with tubo-ovarian high-grade serous carcinoma have germline deleterious mutations in BRCA1 or BRCA2, characteristic of hereditary breast and ovarian cancer syndrome, while somatic mutations have been detected in 3–7%. We set out to determine the mutation rates and optimal tissue requirements for tumor BRCA testing in 291 tissue samples. Initial testing was successful in 78% and deemed indeterminate in 13%. Repeat testing was successful in 67% of retested samples, with an overall success rate of 86%. Clinically significant BRCA variants were identified in 17% of patients. Successful sequencing was dependent on sample type, tumor cellularity and size (p ≤ 0.001) but not on neoadjuvant chemotherapy or age of blocks. In summary, our study shows a 17% tumor BRCA mutation rate, with an overall success rate of 86%. Biopsy and cytology samples and post-chemotherapy specimens can be used, and optimal tumors measure ≥5 mm in size with at least 20% cellularity.Background: Approximately 25% of women diagnosed with tubo-ovarian high-grade serous carcinoma have germline deleterious mutations in BRCA1 or BRCA2, characteristic of hereditary breast and ovarian cancer syndrome, while somatic mutations have been detected in 3–7%. We set out to determine the BRCA mutation rates and optimal tissue requirements for tumor BRCA testing in patients diagnosed with tubo-ovarian high-grade serous carcinoma. Methods: Sequencing was performed using a multiplexed polymerase chain reaction-based approach on 291 tissue samples, with a minimum sequencing depth of 500X and an allele frequency of >5%. Results: There were 253 surgical samples (87%), 35 biopsies (12%) and 3 cytology cell blocks (1%). The initial failure rate was 9% (25/291), including 9 cases (3%) with insufficient tumor, and 16 (6%) with non-amplifiable DNA. Sequencing was successful in 78% (228/291) and deemed indeterminate due to failed exons or variants below the limit of detection in 13% (38/291). Repeat testing was successful in 67% (28/42) of retested samples, with an overall success rate of 86% (251/291). Clinically significant (pathogenic, likely pathogenic) variants were identified in 17% (48/276) of complete and indeterminate cases. Successful sequencing was dependent on sample type, tumor cellularity and size (p ≤ 0.001) but not on neoadjuvant chemotherapy or age of blocks (p > 0.05). Conclusions: Our study shows a 17% tumor BRCA mutation rate, with an overall success rate of 86%. Biopsy and cytology samples and post-chemotherapy specimens can be used for tumor BRCA testing, and optimal tumors measure ≥5 mm in size with at least 20% cellularity.

Identification of Ovarian Cancer Patients Most Likely to Achieve Chemotherapy Response Score 3 Following Neoadjuvant Chemotherapy: Development of a Predictive Nomogram.

Background: The chemotherapy response score (CRS) system is a reproducible prognostic tool for patients receiving neoadjuvant chemotherapy (NACT) for tubo-ovarian high-grade serous carcinoma (HGSC). Achieving CRS 3 following NACT can be used as a surrogate for progression-free survival (PFS) and overall survival (OS). This study aimed to identify predictors of CRS 3 and develop a predictive nomogram.Methods: Data were extracted from 106 HGSC patients receiving NACT. Logistic regression was used to identify independent predictors for CRS 3. A nomogram was established based on the multivariate regression model.Results: All patients received three cycles of NACT, and CRS 3 was observed in 24 (22.6%) patients. Compared with patients in the CRS 1–2 group, patients in the CRS 3 groups had significantly improved PFS (log-rank test P < 0.0001). The multivariate regression analysis identified post-NACT CA125, percent decrease in CA125, post-NACT human epididymis protein 4 (HE4), and post-NACT hemoglobin level as independent predictors of CRS 3. The Hosmer-Lemeshow test showed goodness-of-fit of this regression model (P = 0.272). The nomogram including these factors presented good discrimination (area under the curve = 0.82), good calibration (mean absolute error = 0.039), and a net benefit within the threshold probabilities of CRS 3 > 5%.Conclusions: We validated the prognostic role of the CRS system and developed a nomogram that predicts the possibility of CRS 3 following NACT. The nomogram helps to identify patients who would benefit the most from NACT. More studies are warranted to validate this model.

Pathology of Hereditary Breast and Ovarian Cancer.

Hereditary breast and ovarian cancer (HBOC) syndrome is most commonly characterized by deleterious germline mutations in BRCA1 and BRCA2. HBOC patients are prone to the development of malignant neoplasms in multiple organs including the breast, ovary, and fallopian tube. From a pathological perspective, a number of morphological features have been described in BRCA-associated breast and tubo-ovarian cancers. For example, breast cancers diagnosed in BRCA1-mutation carriers are frequently of a high Nottingham grade and display medullary morphology and a triple-negative and/or a basal-like immunophenotype. In contrast, breast cancers in BRCA2-mutation carriers are similar to sporadic luminal-type tumors that are positive for hormone receptors and lack expression of human epidermal growth factor receptor 2. Cancers arising in the fallopian tube and ovary are almost exclusively of a high-grade serous histotype with frequent Solid, pseudo-Endometrioid, and Transitional cell carcinoma-like morphology (“SET features”), marked nuclear atypia, high mitotic index, abundant tumor infiltrating lymphocytes, and necrosis. In addition, pushing or infiltrative micropapillary patterns of invasion have been described in BRCA-associated metastases of tubo-ovarian high-grade serous carcinomas. Besides BRCA1 and BRCA2 mutations, alterations in a number of other homologous recombination genes with moderate penetrance, including PALB2, RAD51C, RAD51D, BRIP1, and others, have also been described in HBOC patients with varying frequency; however, distinct morphological characteristics of these tumors have not been well characterized to date. In this review, the above pathological features are discussed in detail and a focus is placed on how accurate pathologic interpretation plays an important role in allowing HBOC patients to receive the best possible management.

Lessons learned from understanding chemotherapy resistance in epithelial tubo-ovarian carcinoma from BRCA1and BRCA2mutation carriers.

BRCA1 and BRCA2 are multi-functional proteins and key factors for maintaining genomic stability through their roles in DNA double strand break repair by homologous recombination, rescuing stalled or damaged DNA replication forks, and regulation of cell cycle DNA damage checkpoints. Impairment of any of these critical roles results in genomic instability, a phenotypic hallmark of many cancers including breast and epithelial ovarian carcinomas (EOC). Damaging, usually loss of function germline and somatic variants in BRCA1 and BRCA2, are important drivers of the development, progression, and management of high-grade serous tubo-ovarian carcinoma (HGSOC). However, mutations in these genes render patients particularly sensitive to platinum-based chemotherapy, and to the more innovative targeted therapies with poly-(ADP-ribose) polymerase inhibitors (PARPis) that are targeted to BRCA1/BRCA2 mutation carriers. Here, we reviewed the literature on the responsiveness of BRCA1/2-associated HGSOC to platinum-based chemotherapy and PARPis, and propose mechanisms underlying the frequent development of resistance to these therapeutic agents.

Characterization of TP53-wildtype tubo-ovarian high-grade serous carcinomas: rare exceptions to the binary classification of ovarian serous carcinoma.

While TP53 mutation is widely considered to be a defining feature of tubo-ovarian high-grade serous carcinoma (HGSC), rare TP53-mutation-negative cases have been reported. To gain further insight into this rare subset, a retrospective review was conducted on 25 TP53-wildtype tubo-ovarian HGSCs, constituting 2.5% of 987 HGSCs profiled by the MSK-IMPACT sequencing platform. Consistent with serous differentiation, positive staining for Pax8 and WT1 was present in virtually all TP53-wildtype HGSCs. Other characteristic features of HGSC, such as serous tubal intraepithelial carcinoma, or genetic alterations of CCNE1 and BRCA1/2 were identified in these tumors, furthering supporting their classification as bona fide HGSC, despite lacking TP53 mutations. Overall, the level of chromosomal instability of TP53-wildtype HGSCs was intermediate between low-grade serous carcinoma (LGSC) and TP53-mutated HGSC. Morphologic assessment by observers blinded to mutation status revealed a significant subset of tumors with Grade 2 nuclear atypia (which exceeds the degree of atypia allowed for LGSC, but less than typically encountered for HGSC) combined with micropapillary features (6/19, 32%, chemotherapy-naive TP53-wildtype HGSCs compared to 0/21, 0%, TP53-mutated HGSCs; p = 0.007). Some TP53-wildtype HGSCs harbored driver mutations in KRAS (n = 3), BRAF (n = 1) or NRAS (n = 2). Overall, 10 (40%) cases had "LGSC-like" morphology (i.e., Grade 2 nuclear atypia and micropapillary features) and/or RAS/RAF mutation, and most of these showed a wildtype p53 pattern of expression by immunohistochemistry (7/9, 78%). The remaining TP53-wildtype HGSCs (n = 15, 60%) exhibited severe nuclear atypia (Grade 3) and were morphologically indistinguishable from conventional TP53-mutated HGSC. Despite lacking genetic alterations of TP53, these "usual HGSC-like" tumors often showed evidence of p53 dysfunction, including downregulation of expression ('null' or equivocal p53 staining in 9/14, 64%) or MDM2 amplification (n = 2). Our results support the existence of TP53-wildtype HGSCs, which comprise a heterogeneous group of tumors which may arise via distinct pathogenic mechanisms.

Fallopian tube abnormalities in uterine serous carcinoma

ObjectiveUterine serous carcinoma (USC) is presumed to arise from endometrial intra-epithelial carcinoma (EIC), whereas tubo-ovarian high-grade serous carcinomas have similar precursor lesions in the Fallopian tube, i.e. serous tubal intra-epithelial carcinoma (STIC). The presence of Fallopian tube abnormalities and their clonal relationship to the concurrent USC was investigated. MethodsIn this multicenter study, all patients treated for USC between 1992 and 2017 were retrospectively identified. Histopathological diagnosis of USC, EIC and STIC was revised by an expert pathologist. Additionally, all Fallopian tube sections were immunohistochemically stained (p53 and Ki-67). Fallopian tube abnormalities were classified as either p53 signature, serous tubal intra-epithelial lesion (STIL) or STIC. The USCs and Fallopian tube abnormalities were analyzed by targeted next-generation sequencing. ResultsIn 168 included patients, Fallopian tube abnormalities were found in 27.4% (46/168): p53-signatures in 17.9% (30/168), STILs in 3.0% (5/168) and STICs in 6.5% (11/168). In subgroup analysis, STICs were found in 9.5% (11/115) of patients with at least one section of the fimbriated end embedded. Next-generation sequencing showed identical TP53-mutations in the STIC and corresponding USC. ConclusionsIn conclusion, the presence of Fallopian tube abnormalities was shown in a high percentage of patients with USC, representing either true precursor lesions or metastasized disease.