Recent Insights into Mucinous Ovarian Carcinoma

Genetic landscape of homologous recombination repair and practical outcomes of PARPi therapy in ovarian cancer management

Background

Genetic studies of ovarian cancer (OC) have historically focused on BRCA1/2 mutations, lacking other studies of homologous recombination repair (HRR). Poly (ADP-ribose) polymerase inhibitors (PARPi) exploit synthetic lethality to significantly improve OC treatment outcomes, especially in BRCA1/2 deficiency patients.

Objectives

Our study aims to construct a mutation map of HRR genes in OC and identify factors influencing the efficacy of PARPi.

Design

A retrospective observational analysis of HRR gene variation data from 695 OC patients from March 2019 to February 2022 was performed.

Methods

The HRR gene variation data of 695 OC patients who underwent next-generation sequencing (NGS) in the First Affiliated Hospital of Zhengzhou University were retrospectively collected. Clinical data on the use of PARPi in these patients were also gathered to identify factors that may interfere with the efficacy of PARPi.

Results

Out of 127 pathogenic variants in the BRCA1/2 genes, 104 (81.9%) were BRCA1 mutations, and 23 (18.1%) were BRCA2 mutations. Among the 59 variants of uncertain significance (VUS), 20 (33.9%) were BRCA1, while 39 (66.1%) were BRCA2 mutations. In addition to BRCA1/2, HRR gene results showed that 9 (69%) of 13 were HRR pathway pathogenic variants; and 16 (1.7%) of 116 VUS were Food and Drug Administration (FDA)-approved mutated HRR genes. Notably, the treatment regimen significantly influenced the effectiveness of PARPi, especially when using first-line maintenance therapy, leading to enhanced progression-free survival (PFS) compared to alternative protocols.

Conclusion

Focusing on HRR gene mutations and supporting clinical research about PARPi in OC patients is crucial for developing precision treatment strategies and enhancing prognosis.

A new method for network bioinformatics identifies novel drug targets for mucinous ovarian carcinoma

Mucinous ovarian carcinoma (MOC) is a subtype of ovarian cancer that is distinct from all other ovarian cancer subtypes and currently has no targeted therapies. To identify novel therapeutic targets, we developed and applied a new method of differential network analysis comparing MOC to benign mucinous tumours (in the absence of a known normal tissue of origin). This method mapped the protein-protein network in MOC and then utilised structural bioinformatics to prioritise the proteins identified as upregulated in the MOC network for their likelihood of being successfully drugged. Using this protein-protein interaction modelling, we identified the strongest 5 candidates, CDK1, CDC20, PRC1, CCNA2 and TRIP13, as structurally tractable to therapeutic targeting by small molecules. siRNA knockdown of these candidates performed in MOC and control normal fibroblast cell lines identified CDK1, CCNA2, PRC1 and CDC20, as potential drug targets in MOC. Three targets (TRIP13, CDC20, CDK1) were validated using known small molecule inhibitors. Our findings demonstrate the utility of our pipeline for identifying new targets and highlight potential new therapeutic options for MOC patients.

Multimodal diagnostic strategies and precision medicine in mucinous ovarian carcinoma: a comprehensive approach

Mucinous ovarian carcinoma (MOC) represents a distinct entity within ovarian malignancies, characterized by diagnostic challenges due to its rarity and the potential overlap with other tumor types. The determination of tumor origin is important for precise postsurgical treatment. This article highlights the accurate diagnosis and management of MOC, including the use of imaging modalities, serological tumor markers, immunohistochemistry, and genomic analyses. Transabdominal and transvaginal ultrasonography, complemented by MRI and CT, plays a pivotal role in differentiating MOC from other mucinous tumors and in surgical planning, particularly for fertility preservation. Serological markers like CA19-9, CA-125, and CEA, though not definitive, provide valuable preoperative insights. Immunohistochemistry aids in distinguishing primary MOC from metastatic mucinous carcinomas, while genomic profiling offers the potential for precision medicine through the identification of specific molecular signatures and treatment susceptibilities. Despite advancements in diagnostic techniques, no single method conclusively differentiates between primary and metastatic tumors intraoperatively. The paper reviews the origins, diagnosis, and differential diagnosis of primary mucinous ovarian carcinoma highlights the need for a multimodal diagnostic approach and advocates for the inclusion of MOC patients in clinical trials for personalized therapies, recognizing the heterogeneity of the disease at the molecular level.

Epigenetic regulation in ovarian cancer

Ovarian cancer is one of the diseases that have the highest mortality rate for women, especially women over 50 years old. In the future, incidence and mortality rates are predicted to extend in countries with low HDI. Instability in the structure and function of genetic factors has long been known as a cause of cancer, including ovarian cancer. Besides understanding gene mutations, epigenetic alterations have emerged as another aspect leading to the pathogenesis of ovarian neoplasm. The development and progression of this fatal disease have been found to be associated with abnormalities of epigenetic regulation. DNA methylation, histone modification, and non-coding RNAs-based gene silencing are processes of interest in developing ovarian carcinoma and are also new targets for cancer detection or treatment.

Mucinous cystadenocarcinoma of the breast harbours TRPS1 expressions and PIK3CA alterations

AIMS

Breast mucinous cystadenocarcinoma (BMCA) is a rare tumour recently recognised as a distinct entity by the World Health Organisation Tumour Classification Series. BMCA is a triple-negative tumour that lacks specific immunohistochemical markers; therefore, distinguishing it from mimickers such as ovarian and pancreatic cystadenocarcinomas requires careful clinicopathological correlation. Due to its rarity, little is known about the molecular alterations that underlie BMCA.

METHODS AND RESULTS

In this study, we used immunohistochemical staining methods to investigate TRPS1 (trichorhinophalangeal syndrome type 1) expression in BMCA and compare it to expression in ovarian and pancreatic mucinous cystadenocarcinomas. We also collected tumour samples from three BMCA patients for molecular analysis by MALDI-TOF mass spectrometry, real-time polymerase chain reaction, whole exome sequencing and fluorescence in-situ hybridisation. TRPS1 immunoreactivity was found only in BMCA tumour cells and not in the ovarian and pancreatic counterparts. One of the three BMCA tumours also showed a PIK3CA hot-spot mutation, which was confirmed by whole genome next-generation sequencing (NGS). No KRAS, NRAS, BRAF or AKT mutations were found.

CONCLUSIONS

To our knowledge, this is the first demonstration of TRPS1 expression in BMCA patients and the first identification of a PIK3CA hotspot mutation in these tumours. These findings provide insights into the molecular mechanisms underlying BMCA tumorigenesis and suggest a potential drug target for this rare and poorly understood cancer.

Anaplastic Carcinoma Arising From a Mural Nodule in Benign Mucinous Cystadenoma

Giant abdominopelvic tumors continue to present a diagnostic and therapeutic challenge for all surgeons despite all the advances in the world of imaging. Particularly, one of the most important challenges is to determine its probable origin for adequate surgical planning. Even though mostly all of these tumors are benign ovarian tumors, extraordinarily, malignant mural nodules may develop from the wall of these benign tumors, carrying an invariable unfavorable prognosis for the patient. This case highlights the importance of a correct diagnostic approach using ultrasound and abdominal computed tomography scans and confirming the diagnosis through a histopathologic examination. The treatment for these cases is surgical resection and posterior oncological treatment if needed. This case shows how timely treatment is one of the principal determinators of morbidity and mortality.

Synergy of the microRNA Ratio as a Promising Diagnosis Biomarker for Mucinous Borderline and Malignant Ovarian Tumors

Epithelial ovarian cancers (EOCs) are a heterogeneous collection of malignancies, each with their own developmental origin, clinical behavior and molecular profile. With less than 5% of EOC cases, mucinous ovarian carcinoma is a rare form with a poor prognosis and a 5-year survival of 11% for advanced stages (III/IV). At the early stages, these malignant forms are clinically difficult to distinguish from borderline (15%) and benign (80%) forms with a better prognosis due to the large size and heterogeneity of mucinous tumors. Improving their diagnosis is therefore a challenge with regard to the risk of under-treating a malignant form or of unnecessarily undertaking radical surgical excision. The involvement of microRNAs (miRNAs) in tumor progression and their potential as biomarkers of diagnosis are becoming increasingly recognized. In this study, the comparison of miRNA microarray expression profiles between malignant and borderline tumor FFPE samples identified 10 down-regulated and 5 up-regulated malignant miRNAs, which were validated by individual RT-qPCR. To overcome normalization issues and to improve the accuracy of the results, a ratio analysis combining paired up-regulated and down-regulated miRNAs was performed. Although 21/50 miRNA expression ratios were significantly different between malignant and borderline tumor samples, any ratio could perfectly discriminate the two groups. However, a combination of 14 pairs of miRNA ratios (double ratio) showed high discriminatory potential, with 100% of accuracy in distinguishing malignant and borderline ovarian tumors, which suggests that miRNAs may hold significant clinical potential as a diagnostic tool. In summary, these ratio miRNA-based signatures may help to improve the precision of histological diagnosis, likely to provide a preoperative diagnosis in order to adapt surgical procedures.

Development and validation of a nomogram to predict cancer-specific survival of mucinous epithelial ovarian cancer after cytoreductive surgery

BACKGROUND

Mucinous epithelial ovarian cancer (mEOC) is a relatively uncommon subtype of ovarian cancer with special prognostic features, but there is insufficient research in this area. This study aimed to develop a nomogram for the cancer-specific survival (CSS) of mEOC based on Surveillance, Epidemiology, and End Results (SEER) database and externally validate it in National Union of Real World Gynecological Oncology Research and Patient Management (NUWA) platform from China.

METHODS

Patients screened from SEER database were allocated into training and internal validation cohort in a ratio of 7: 3, with those from NUWA platform as an external validation cohort. Significant factors selected by Cox proportional hazard regression were applied to establish a nomogram for 3-year and 5-year CSS. The performance of nomogram was assessed by concordance index, calibration curves and Kaplan-Meier (K-M) curves.

RESULTS

The training cohort (n = 572) and internal validation cohort (n = 246) were filtered out from SEER database. The external validation cohort contained 186 patients. Baseline age, tumor stage, histopathological grade, lymph node metastasis and residual disease after primary surgery were significant risk factors (p < 0.05) and were included to develop the nomogram. The C-index of nomogram in training, internal validation and external validation cohort were 0.869 (95% confidence interval [CI], 0.838-0.900), 0.839 (95% CI, 0.787-0.891) and 0.800 (95% CI, 0.738-0.862), respectively. The calibration curves of 3-year and 5-year CSS in each cohort showed favorable agreement between prediction and observation. K-M curves of different risk groups displayed great discrimination.

CONCLUSION

The discrimination and goodness of fit of the nomogram indicated its satisfactory predictive value for the CSS of mEOC in SEER database and external validation in China, which implies its potential application in different populations.

Histological and Genetic Diversity in Ovarian Mucinous Carcinomas: A Pilot Study

Tumor heterogeneity remains an ongoing challenge in the field of cancer therapy. Intratumor heterogeneity significantly complicates the diagnosis of cancer and presents challenging clinical problems due to resistance to drug therapy. This study aimed to elucidate the genetic changes histologically (mucinous cystadenoma (MCA), mucinous borderline tumor (MBT), and mucinous ovarian carcinoma (MOC)) in a portion of mucinous ovarian tumors within the same sample. Seven tumor samples obtained from different patients were used to evaluate the genetic mutations in each component. Intratumor genetic heterogeneity was observed in all patients; among them, BRAF (V600E) and p53 (T118I, P142S, T150I, and T170M) point mutations were observed in the MBT component, while KRAS (G12D and G13D) and PIK3CA (E545K) mutations were found in the MOC component. The current findings suggest that diverse genetic alterations occur in mucinous tumors, according to tumor histology. Tumor heterogeneity and genetic diversity in mucinous ovarian tumors might be the cause of treatment failure. Knowledge of intertumor heterogeneity may lead to an increased understanding of the tumor response to treatment.

Trefoil factor family proteins as potential diagnostic markers for mucinous invasive ovarian carcinoma

Introduction

Ovarian cancer (OC) is the leading cause of gynecological cancer-related death. Of the main OC histologic subtypes, invasive mucinous carcinomas (MC) account for only 3% of OC cases and are frequently associated with favorable prognosis. Nevertheless, MCs differ greatly from the other OC histotypes in clinical, pathological, and biological behavior. However, the origin and molecular pathogenesis of MC are not yet fully understood. Therefore, identification of novel diagnostic markers could potentially facilitate early diagnosis of OC, particularly the MC histotype, thereby leading to the development of histotype-specific treatment regimens and improved survival rates.

Methods

In the present study, Trefoil factor gene family members (TFF1, TFF2 and TFF3) were identified as MC histotype-specific biomarkers using RNA sequencing (RNA-seq) data for 95 stage I-II OCs. The diagnostic value of TFF1, TFF2 and TFF3 was then evaluated by immunohistochemistry on 206 stage I-II OCs stratified by histotype (high-grade serous carcinoma [HGSC], endometrioid carcinoma [EC], clear cell carcinoma [CCC], and MC).

Results

We showed significantly elevated intracytoplasmic protein expression levels for TFF1, TFF2 and TFF3 in MC samples, thereby revealing an association between expression of Trefoil factor gene family members and the MC histotype. Taken together, these findings suggest that the TFF proteins may play a pivotal role in tumor initiation and progression for the MC histotype.

Conclusion

Taken together, these findings suggest that the TFF proteins may play a pivotal role in tumor initiation and progression for the MC histotype. Moreover, these novel histotype-specific diagnostic biomarkers may not only improve patient stratification of early-stage ovarian carcinomas but may also be candidates for the development of molecular targeted therapies.

Evaluation of Outcomes of Mucinous Ovarian Cancer Treated at a Tertiary Care Cancer Hospital in Pakistan

Syed Abdul Mannan HamdaniObjective  To evaluate the clinicopathological features and survival outcomes of mucinous ovarian cancer (MOC) patients in an Asian population. Study Design  Descriptive observational study. Place and Duration of Study  Shaukat Khanum Memorial Cancer Hospital, Lahore, Pakistan, from January 2001 to December 2016. Methods  Data of MOC were evaluated for demographics, tumor stage, clinical characteristics, tumor markers, treatment modalities, and outcomes from electronic Hospital Information System. Results  Nine-hundred patients with primary ovarian cancer were reviewed, out of which 94 patients (10.4%) had MOC. The median age was 36 ± 12.4 years. The most common presentation was abdominal distension 51 (54.3%), while the rest presented with abdominal pain and irregular menstruation. Using FIGO (The International Federation of Gynecology and Obstetrics) staging, 72 (76.6%) had stage I, 3 (3.2%) stage II, stage III in 12 (12.8%), and 7 (7.4%) had stage IV disease. The majority of patients 75 (79.8%) had early-stage (stage I/II), while 19 (20.2%) presented with advanced-stage (III & IV). The median follow-up duration was 52 months (range 1-199 months). Among patients with early-stage (I&II), 3- and 5-year progression-free survival (PFS) was 95%, while for advanced stage (III&IV), PFS was 16% and 8%, respectively. The overall survival (OS) in early-stage I&II was 97%, while for advanced stages III & IV, the OS was 26%. Conclusion  MOC is a challenging and rare subtype of ovarian cancer requiring special attention and recognition. Most patients treated at our center presented with early stages and had excellent outcomes, while advanced-stage disease had dismal results.

Bilateral ovarian mucinous carcinoma (stage III) with omental involvement and incidental hydronephrosis: A rare case report

INTRODUCTION

Though ovarian malignancies are common, mucinous ovarian carcinomas of high grade are rare. They usually occur in a young female under 40 years of age. Here, we present a case of mucinous ovarian carcinoma (stage III), with omental involvement and incidental hydronephrosis in a 67-year-old female patient.

CASE PRESENTATION

A 67-year-old female patient presented to us with a history of lower abdominal pain for 2 months and per-vaginal discharge for the last 6 days. On deep palpation of the abdomen, a nodular mass occupying the suprapubic region was found. Bimanual palpation revealed a mass on the right and left adnexa. After visualization of septate cystic mass bilaterally on CECT, she was planned for staging laparotomy with bilateral salpingo-oophorectomy (BSO) with infra-colic omentectomy with peritoneal cytology. Incidentally, a horseshoe-shaped kidney with right mild hydronephrosis was found. After surgery and histopathologic examination, mucinous ovarian carcinoma (stage III), with omental involvement was confirmed.

DISCUSSION

Mucinous ovarian carcinomas are rare malignancies, with different natural history, molecular profile, and prognosis as compared to other epithelial tumors of the ovary. These carcinomas can be either primary or secondary (those metastasized to the ovary from elsewhere), and this differentiation is essential. The therapeutic approach to the patients depends upon the stage at which these carcinomas are diagnosed.

CONCLUSION

Mucinous ovarian carcinomas are rare and have unique features among the epithelial ovarian carcinomas. Appreciation of these features will surely make a positive impact in improving the management and thus the prognosis of these carcinomas.

Mucinous Ovarian Tumors With Anaplastic Mural Nodules: Case Report

Ovarian mucinous cystic tumors may be associated with various types of mural nodules, which can be classified as benign or malignant (anaplastic carcinoma, sarcoma, carcinosarcoma). However, anaplastic malignant nodules have rarely been reported. Here, we present a case of a 35-year-old woman who presented with abdominal discomfort. Ultrasonography showed a large cystic mass in the pelvic and abdominal cavities measuring 337 × 242 mm. Abdominal computed tomography revealed upper anterior and posterior uterine pelvic cystic lesions based on multiple nodule partition walls and classes. During hospitalization, the patient underwent exploratory laparotomy, which revealed a poorly differentiated ovarian malignant tumor, and subsequent surgical excision was performed. The pathological analysis of the surgical samples of the right ovary revealed a mucinous ovarian tumor, while the mural nodules were classified as anaplastic carcinoma. After surgery, the patient started receiving chemotherapy. Unfortunately, the patient died 6 months later. Mucinous tumor occurring with an anaplastic carcinoma is rare, and the current diagnostic methods are not sufficient in providing an early and accurate diagnosis. Most patients are already in the advanced stage upon diagnosis and combined with poorly differentiated pathological features, the prognosis is extremely poor. Clinicians need to improve the clinical evaluation before surgery and conduct preoperative preparation and communication to improve the prognosis of patients as much as possible.

Prognosis in primary mucinous ovarian carcinoma: focusing on the five pathological findings indicating metastatic mucinous carcinoma to the ovary

Objective

Pathological features indicating metastatic mucinous carcinoma to the ovary (MMCO) have been rarely reported in primary mucinous ovarian carcinoma (PMOC). However, little is known about how often they are observed in PMOC and how they relate to patient prognosis. In this study, we investigated the pathological features indicating MMCO in a large cohort of PMOCs and analyzed their association with patient prognosis.

Methods

We reviewed surgically treated PMOC patients diagnosed at the Seoul National University Hospital from 1995 to 2019, according to the updated WHO classification, and investigated the presence of pathological features indicating MMCO.

Results

A total of 144 patients with PMOCs were included. The 5 pathological findings indicating MMCO, including an infiltrative invasive pattern, the absence of benign or borderline components, a smaller tumor size, the presence of signet ring cells and the presence of extracellular mucin were observed in PMOC (21.6%, 43.1%, 20.8%, 4.3% and 12.9%, respectively), and were significantly correlated with poor overall and progression-free survival rates in PMOC. The patient’s prognosis worsened as the extent of the infiltrative invasive pattern increased (p<0.001). In addition, the prognostic power was stronger when the 5 pathological factors were analyzed together (new grouping system) than when analyzed individually (p<0.001) and the new grouping system was identified as an independent prognostic factor regardless of FIGO stage.

Conclusion

Five pathological findings indicating MMCO in PMOC were significantly associated with poor prognosis in PMOC patients. Also, the new grouping system combining these findings was identified as an independent prognostic factor.

Pathologic features indicating metastatic mucinous carcinoma to the ovary (MMCO) have been rarely reported in primary mucinous ovarian carcinomas (PMOCs). We found the 5 pathological findings indicating MMCO in PMOC were significantly associated with poor prognosis in PMOC patients.

The cell of cancer origin provides the most reliable roadmap to its diagnosis, prognosis (biology) and therapy

Cancers arise from single transformed cells from virtually every organ of the body, divide in a relatively uncontrolled manner, and metastasize widely. A search for a "magic bullet" to precisely diagnose, characterize, and ultimately treat cancer has largely failed because cancer cells do not differ significantly from their organ-specific cells of origin. Instead of searching for genomic, epigenetic, transcriptional, and translational differences between cancers and their cells of origin, we should paradoxically focus on what cancer cells have in common with their untransformed cells of origin. This redirected search will lead to improved diagnostic and therapeutic strategies where therapeutic index considerations and drug-limiting toxicities can largely be circumvented. We cite three cancer examples that illustrate this paradigm-shifting strategy: pseudomyxoma peritonei (PP), metastasis of unknown origin (cancers of unknown primary) (MUO), and cancers that arise from potentially dispensable organs (CAD). In each of these examples, the cell of cancer origin still provides the most reliable road map to its diagnosis, prognosis (biology), and therapy.

Future Screening Prospects for Ovarian Cancer

Simple Summary

Ovarian cancer (OC) has the highest mortality rate of all gynecological cancers. It is usually diagnosed in late stages (FIGO III-IV), and therefore, overall survival is very poor. If diagnosed at the early stages, ovarian cancer has a 90% five-year survival rate. Liquid biopsy has a good potential to improve early ovarian cancer detection and is discussed in this review.

Abstract

Current diagnostic tools used in clinical practice such as transvaginal ultrasound, CA 125, and HE4 are not sensitive and specific enough to diagnose OC in the early stages. A lack of early symptoms and an effective asymptomatic population screening strategy leads to a poor prognosis in OC. New diagnostic and screening methods are urgently needed for early OC diagnosis. Liquid biopsies have been considered as a new noninvasive and promising method, using plasma/serum, uterine lavage, and urine samples for early cancer detection. We analyzed recent studies on molecular biomarkers with specific emphasis on liquid biopsy methods and diagnostic efficacy for OC through the detection of circulating tumor cells, circulating cell-free DNA, small noncoding RNAs, and tumor-educated platelets.

Clinical value of N-acetyl mucinous compounds and lipid peaks in differentiating benign and malignant ovarian mucinous tumors by MR spectroscopy

PURPOSE

To retrospectively evaluate the clinical significance of the peaks of N-acetyl mucinous compounds (NAMC) at 2 ppm and lipid at 1.3 ppm in in-vivo proton magnetic resonance (MR) spectroscopy for distinguishing benign and malignant mucinous tumors in patients with ovarian masses.

METHODS

MR spectroscopy was performed in patients with pathologically diagnosed mucinous ovarian tumors at 3 T MRI system. The peaks of NAMC, lipid, and total choline compounds (tCho) were classified into three classes in comparison with the noise level by visual estimation. The NAMC concentration was quantified relative to unsuppressed water by using LCModel analysis.

RESULTS

A total of 27 ovarian mucinous tumors in 27 patients were included in this study. The NAMC peak was observed in all 27 mucinous tumors, and the lipid peak was observed in 14 of 27 tumors: 1 of 9 benign tumors (11%), and 13 of 18 malignant tumors (11 borderline malignancies and 7 carcinomas) (72%). The presence of the lipid peak for the diagnosis of malignant mucinous tumor showed generally better diagnostic ability than MR imaging, with a sensitivity of 72%, specificity of 89%, accuracy of 78%, PPV of 93%, and NPV of 62%. The concentration of the NAMC in malignant mucinous tumors tended to be higher than that in benign mucinous tumors, but there was no statistically significant difference.

CONCLUSIONS

The bimodal peaks of NAMC and lipid are suggestive of malignant mucinous tumors, and the presence of the lipid peak may be useful in distinguishing benign from malignant ovarian mucinous tumors.

Characterization and clinical significance of the CADM1/HER2/STAT3 axis in serous ovarian tumors

The subtypes of serous ovarian tumors (SOTs), including benign serous cystadenoma, serous borderline tumor (SBT), low-grade serous ovarian carcinoma (LGSC), and high-grade serous ovarian carcinoma (HGSC), remain poorly understood. Herein, we aimed to characterize the cell adhesion molecule 1 (CADM1)/signal transducer and activator of transcription 3 (STAT3)/human epidermal growth factor receptor 2 (HER2) axis and identify its clinical significance in patients with serous cystadenoma, SBT, LGSC, and HGSC.The immunohistochemical expression of CADM1, HER2, and STAT3 was assessed in 180 SOT specimens, and its association with clinical data was determined.High levels of CADM1 expression were detected in 100% of serous cystadenomas and 83.33% of SBTs, while a loss of CADM1 expression was observed in 44% of LGSCs and 72.5% of HGSCs. Relative to the levels in benign cystadenomas and SBTs, higher levels of HER2 and STAT3 expression were observed in LGSCs and aggressive HGSCs. Furthermore, the expression profile of the CADM1/HER2/STAT3 axis was significantly associated with histologic type, International Federation of Gynecology and Obstetrics stage, and lymph node metastasis in patients with SOT.Our study identified the changes in the CADM1/HER2/STAT3 axis that were closely associated with the clinical behavior of SOTs. These molecular data may provide new insights into SOT carcinogenesis and aid in the diagnosis and treatment of patients with SOT.

Phagocytosis: Sweet Repulsions via the Glycocalyx

New work shows that the glycocalyx meshwork on the surface of macrophages prevents phagocytic receptors from binding their ligands by two means - electrostatic charge and steric hindrance. Components of this barrier are present on pathogenic and malignant targets that elude phagocytosis.

Current and Futuristic Roadmap of Ovarian Cancer Management: An Overview

Ovarian cancer (OC) is the most lethal gynecological malignancy among women worldwide. In most cases, it is diagnosed late at an advanced stage and does not respond well to existing therapies leading to its poor prognosis. In addition, other factors including epidemiological, complex histological diversity, multiple molecular alterations, and overlapping signaling pathways are also important contributors to poor disease outcome. Efforts have continued to develop a deeper understanding of the molecular pathogenesis and altered signaling nodes that provide hope for better clinical management through the development of novel approaches for early diagnosis, disease subtyping, prognosis, and therapy. In this chapter, we provide a detailed overview of OC and its histological subtypes and discuss prevalent molecular aberrations and active signaling pathways that drive OC progression. We also summarize various diagnostic and prognostic markers and therapeutic approaches currently being employed and discuss emerging findings that hold the potential to change the future course of OC management.

Analysis of Multimerin 1 (MMRN1) expression in ovarian cancer

Ovarian cancer, the most lethal gynecological cancer, is the fifth most common cause of cancer-related deaths in women. A cost-effective and non-invasive early screening method for ovarian cancer is required to reduce the high mortality rate. Saliva is a clinically informative unique fluid, which is useful for novel approaches to prognosis, clinical diagnosis, and monitoring for non-invasive detection of disease. Multimerin1 (MMRN1) is a di-sulfide linked homo-polymeric glycoprotein from EMILIN family. Altered expression of MMRN1 has been reported in hepatocellular carcinoma, cervical cancer, and ovarian cancer. But, its role in epithelial ovarian cancer (EOC) is not clear and well documented. In this study, expression of Multimerin 1 was validated in saliva and tissues of EOC patients and age-matched controls by western blotting, ELISA, RT-PCR, and immunohistochemistry. Significant over expression of MMRN1 was observed by western blot and ELISA in saliva samples of EOC patients. The average concentration of MMRN1 in the saliva of healthy controls was 28.7 pg/ml (SE ± 1.76), 42.53 pg/ml (SE ± 4.06) in low grade and 52.91 pg/ml (SE ± 4.24) with p < 0.01 in high-grade EOC. Upregulated cytoplasmic expression of MMRN1 was observed in EOC tissue by immunohistochemistry. Our results suggest that MMRN1 expression is associated with EOC progression and MMRN1 may be potential biomarker candidates for early-stage EOC detection however further experiments are required in a large cohort to establish this proposition. Also, saliva can be explored as a novel medium for ovarian cancer diagnosis.

Ovarian mucinous neoplasms, intestinal type, in premenopausal patients, develop in abnormal ovaries

Although several studies have addressed different aspects of mucinous neoplasms arising in the ovary, such as their clinicopathologic features, immunohistochemical profile, and molecular characteristics, no study has presented an analysis of the ovarian tissue where these neoplasms arise. In this study, we included 196 cases of intestinal-type ovarian mucinous neoplasms in premenopausal patients. Our main goal was to perform a rigorous examination of the ovarian tissue surrounding these neoplasms. We also reviewed the clinicopathologic features of these cases. For comparison, the background ovarian tissue in 85 cases of ovarian serous neoplasm and in 29 cases of metastatic neoplasms to the ovary, as well as 57 normal ovaries, was examined. All the patients in this study, which included those with mucinous and with serous neoplasms primary in the ovary, those with metastatic tumors to the ovaries, and those with normal ovaries, were also premenopausal. Patients affected by ovarian mucinous neoplasms ranged in age from 13 to 52 years (median = 36 years). Nulligravidity was seen in 50%, 32%, and 22% of patients with mucinous carcinomas, mucinous borderline neoplasms, and mucinous cystadenomas, respectively. Ovarian mucinous intestinal neoplasms arise in abnormal ovaries characterized by two important features: (1) an abnormal ovarian cortex, seen in 95% of the cases, which is hypocellular or with no distinction between the cellular cortex and medulla, and (2) a remarkable paucity of primordial follicles. The abnormalities detected in the background ovarian tissue might provide insights into the tumorigenesis of these neoplasms and might facilitate their distinction from metastasis to the ovary, in premenopausal patients.

Multimodality Imaging Approach to Ovarian Neoplasms with Pathologic Correlation

Ovarian neoplasms can be categorized on the basis of histopathologic features into epithelial surface cell tumors, germ cell tumors, sex cord-stromal tumors, and metastases. While their imaging appearance is often nonspecific, it closely parallels the gross pathologic appearance, and radiologic-pathologic correlation is helpful to aid in a deeper understanding of the subtypes. Epithelial cell neoplasms are the most common category, and they can be benign, borderline, or malignant. Specific subtypes include serous (most common), mucinous, seromucinous, endometrioid, clear cell, Brenner, and undifferentiated. High-grade serous cystadenocarcinoma accounts for the majority of malignant ovarian tumors and the most ovarian cancer deaths. While serous neoplasms are often unilocular and bilateral, mucinous neoplasms are larger, unilateral, and multilocular. Solid components, thickened septa, and papillary projections, particularly with vascularity, indicate borderline or malignant varieties. Endometrioid and clear cell carcinomas can arise within endometriomas. Fibrous tumors (cystadenofibroma, adenofibroma, fibroma or fibrothecoma, and Brenner tumors) demonstrate low T2-weighted signal intensity of their solid components, while teratomas contain lipid. The nonspecific imaging appearance of additional malignant ovarian germ cell tumors can be narrowed with tumor marker profiles. Sex cord-stromal tumors are often solid, and secondary signs from their hormonal secretion can be a clue to their diagnosis. The authors review the anatomy of the ovary and distal fallopian tube, the proposed origins of the histologic subtypes of tumors, the clinical features and epidemiology of ovarian neoplasms, and the applications of US, CT, and MRI in imaging ovarian neoplasms. The main focus is on the radiologic and pathologic features of the multiple ovarian neoplasm subtypes. An algorithmic approach to the diagnosis of ovarian neoplasms is presented. Online supplemental material is available for this article. ^©RSNA, 2020.

Transcription factors in epithelial ovarian cancer: histotype-specific drivers and novel therapeutic targets

Transcription factors (TFs) are major contributors to cancer risk and somatic development. In preclinical and clinical studies, direct or indirect inhibition of TF-mediated oncogenic gene expression profiles have proven to be effective in many tumor types, highlighting this group of proteins as valuable therapeutic targets. In spite of this, our understanding of TFs in epithelial ovarian cancer (EOC) is relatively limited. EOC is a heterogeneous disease composed of five major histologic subtypes; high-grade serous, low-grade serous, endometrioid, clear cell and mucinous. Each histology is associated with unique clinical etiologies, sensitivity to therapies, and molecular signatures - including diverse transcriptional regulatory programs. While some TFs are shared across EOC subtypes, a set of TFs are expressed in a histotype-specific manner and likely explain part of the histologic diversity of EOC subtypes. Targeting TFs present with unique opportunities for development of novel precision medicine strategies for ovarian cancer. This article reviews the critical TFs in EOC subtypes and highlights the potential of exploiting TFs as biomarkers and therapeutic targets.

Targeting UDP-glucose dehydrogenase inhibits ovarian cancer growth and metastasis

More than 70% of patients with ovarian cancer are diagnosed in advanced stages. Therefore, it is urgent to identify a promising prognostic marker and understand the mechanism of ovarian cancer metastasis development. By using proteomics approaches, we found that UDP-glucose dehydrogenase (UGDH) was up-regulated in highly metastatic ovarian cancer TOV21G cells, characterized by high invasiveness (TOV21GHI ), in comparison to its parental control. Previous reports demonstrated that UGDH is involved in cell migration, but its specific role in cancer metastasis remains unclear. By performing immunohistochemical staining with tissue microarray, we found overexpression of UGDH in ovarian cancer tissue, but not in normal adjacent tissue. Silencing using RNA interference (RNAi) was utilized to knockdown UGDH, which resulted in a significant decrease in metastatic ability in transwell migration, transwell invasion and wound healing assays. The knockdown of UGDH caused cell cycle arrest in the G0 /G1 phase and induced a massive decrease of tumour formation rate in vivo. Our data showed that UGDH-depletion led to the down-regulation of epithelial-mesenchymal transition (EMT)-related markers as well as MMP2, and inactivation of the ERK/MAPK pathway. In conclusion, we found that the up-regulation of UGDH is related to ovarian cancer metastasis and the deficiency of UGDH leads to the decrease of cell migration, cell invasion, wound healing and cell proliferation ability. Our findings reveal that UGDH can serve as a prognostic marker and that the inhibition of UGDH is a promising strategy for ovarian cancer treatment.

Modeling the Diversity of Epithelial Ovarian Cancer through Ten Novel Well Characterized Cell Lines Covering Multiple Subtypes of the Disease

Cancer cell lines are amongst the most important pre-clinical models. In the context of epithelial ovarian cancer, a highly heterogeneous disease with diverse subtypes, it is paramount to study a wide panel of models in order to draw a representative picture of the disease. As this lethal gynaecological malignancy has seen little improvement in overall survival in the last decade, it is all the more pressing to support future research with robust and diverse study models. Here, we describe ten novel spontaneously immortalized patient-derived ovarian cancer cell lines, detailing their respective mutational profiles and gene/biomarker expression patterns, as well as their in vitro and in vivo growth characteristics. Eight of the cell lines were classified as high-grade serous, while two were determined to be of the rarer mucinous and clear cell subtypes, respectively. Each of the ten cell lines presents a panel of characteristics reflective of diverse clinically relevant phenomena, including chemotherapeutic resistance, metastatic potential, and subtype-associated mutations and gene/protein expression profiles. Importantly, four cell lines formed subcutaneous tumors in mice, a key characteristic for pre-clinical drug testing. Our work thus contributes significantly to the available models for the study of ovarian cancer, supplying additional tools to better understand this complex disease.

Mucinous borderline ovarian tumors with BRAFV600E mutation may have low risk for progression to invasive carcinomas

Purpose

Mucinous ovarian carcinomas (MOCs) are relatively rare. It has been proposed that a subset of mucinous cystadenomas (MCAs) may progress to mucinous borderline tumors (MBTs), and then to MOCs. KRAS is the predominantly mutated gene in MOC; however, other associated mutations and the mechanism underlying carcinogenesis in MOC remain unclear. Here, we assessed molecular genetic alterations in mucinous ovarian tumors and constructed mutation profiles.

Methods

Using the Sanger sequencing method, we assessed genetic mutations (KRAS, BRAF, TP53, and PIK3CA) in 16 cases of MOC, 10 cases of MBT, and 12 cases of MCA.

Results

Among MOC cases, the prevalence of G12D and G13D KRAS mutations was 43.8% (7/16). No MOC cases showed V600E BRAF and TP53 mutations. Among MBT cases, the prevalence of G12D KRAS mutation was 20.0% (2/10), those of TP53 and PIK3CA mutations were nil, and that of V600E BRAF mutation was 40% (4/10). None of the genetic mutations assessed were detected among MCA cases.

Conclusion

These results suggest that MBT with V600E BRAF mutation may rarely progress to MOC, while MBT with G12D or G13D KRAS mutation may more commonly progress to MOC.

Identification of PLK1 as a New Therapeutic Target in Mucinous Ovarian Carcinoma

Mucinous epithelial ovarian cancer (mEOC) is a rare subset of epithelial ovarian cancer. When diagnosed at a late stage, its prognosis is very poor, as it is quite chemo-resistant. To find new therapeutic options for mEOC, we performed high-throughput screening using a siRNA library directed against human protein kinases in a mEOC cell line, and polo-like kinase1 (PLK1) was identified as the kinase whose downregulation interfered with cell proliferation. Both PLK1 siRNA and two specific PLK1 inhibitors (onvansertib and volasertib) were able to inhibit cell growth, induce apoptosis and block cells in the G2/M phase of the cell cycle. We evaluated, in vitro, the combinations of PLK1 inhibitors and different chemotherapeutic drugs currently used in the treatment of mEOC, and we observed a synergistic effect of PLK1 inhibitors and antimitotic drugs. When translated into an in vivo xenograft model, the combination of onvansertib and paclitaxel resulted in stronger tumor regressions and in a longer mice survival than the single treatments. These effects were associated with a higher induction of mitotic block and induction of apoptosis, similarly to what was observed in vitro. These data suggest that the combination onvansertib/paclitaxel could represent a new active therapeutic option in mEOC.

Establishment of patient-derived tumor xenograft models of mucinous ovarian cancer

Mucinous ovarian carcinoma (mEOC) represents a rare subtype of epithelial ovarian cancer, accounting for 3-4% of all ovarian carcinomas. The rarity of this tumor type renders both the preclinical and clinical research compelling. Very few preclinical in vitro and in vivo models exist. We here report the molecular, metabolic and pharmacological characterization of two patient derived xenografts (PDXs) from mEOC, recently obtained in our laboratory. These PDXs maintain the histological and molecular characteristics of the patient's tumors they derived from, including a wild type TP53. Gene expression analysis and metabolomics profile suggest that they differ from high grade serous/endometrioid ovarian carcinoma PDXs. The pharmacological characterization was undertaken testing the in vivo antitumor activity of both cytotoxic agents (cisplatin, paclitaxel, yondelis, oxaliplatin and 5-fluorouracile) and targeted agents (bevacizumab and lapatinib). These newly established mucinous PDXs do recapitulate mEOC and will be of value in the preclinical development of possible new therapeutic strategies for this tumor type.

Risk of specific types of ovarian cancer after borderline ovarian tumors in Denmark: A nationwide study

Population-based evidence regarding risk of ovarian cancer after a borderline ovarian tumor (BOT) is sparse. We aimed to examine the incidence of specific types of ovarian cancer in women with serous or mucinous BOTs in a nationwide cohort study with up to 36 years of follow-up. Using the nationwide Danish Pathology Data Bank, we identified 4,281 women with a BOT (2,058 serous BOTs and 2,223 mucinous BOTs) in Denmark during 1978-2012. We computed standardized incidence ratios (SIRs) to compare the incidence of ovarian cancer among women with BOTs compared to general population rates. We found that a serous BOT was especially and strongly associated with subsequent serous ovarian cancer (SIR = 9.2; 95% CI: 6.8-12.2), and that a mucinous BOT was strongly related to mucinous ovarian cancer (SIR = 18.6; 95% CI: 10.8-29.8). The SIRs remained elevated ≥10 years after a serous BOT and up to 5-9 years after a mucinous BOT. The increased incidence of serous ovarian cancer in women with a serous BOT was mostly pronounced in women <50 years at the serous BOT diagnosis. In conclusion, women with a serous BOT experience long-term increased incidence of serous ovarian cancer, and women with a mucinous BOT have long-term elevated incidence of mucinous ovarian cancer compared to the general population. This is the first population-based study to show compelling evidence of the histo-specific increased risk of ovarian cancer following specific types of BOTs. Thus, these results are supportive of the hypothesis that BOTs may be precursor lesions to carcinomas of the corresponding histologic type.

Germline and somatic mutations of homologous recombination-associated genes in Japanese ovarian cancer patients

We explored the frequency of germline and somatic mutations in homologous recombination (HR)-associated genes in major histological types of ovarian cancer. We performed targeted sequencing to assess germline and somatic mutations of 16 HR-associated genes and 4 mismatch repair (MMR) genes among 207 ovarian cancer patients (50 high-grade serous carcinomas (HGSC), 99 clear cell carcinomas (CCC), 39 endometrioid carcinomas (EC), 13 mucinous carcinomas (MC), and 6 low-grade serous carcinomas (LGSC)). Germline or somatic mutations of HR-associated genes were detected in 44% of HGSC, 28% of CCC, 23% of EC, 16% of MC, and 17% of LGSC patients. The profile of HR-associated gene mutations was remarkably different among each histological type. Germline BRCA1/2 mutations were frequently detected in HGSC and were rarely observed in CCC, EC, and MC patients. ATM somatic mutation was more frequently detected in CCC (9%) and EC patients (18%) than in HGSC patients (4%). There was a positive correlation between MMR gene mutations and HR-associated gene mutations (p = 0.0072). Our findings might be useful in selection of ovarian cancer patients that should be treated with PARP inhibitors.

Appendiceal mucinous neoplasm mimics ovarian tumors: Challenges for preoperative and intraoperative diagnosis and clinical implication

OBJECTIVE

The aim of this study was to investigate the clinicopathological characteristics of appendiceal mucinous neoplasm that had been preoperatively misdiagnosed as a mucinous ovarian tumor and to discuss the clinical impacts of misdiagnosis.

METHODS

Seventy-eight patients with a final pathologic diagnosis of appendiceal mucinous neoplasm during a 10-year period were retrospectively reviewed. All patients were diagnosed with ovarian tumor before treatment. A univariate analysis was performed to evaluate predictors of the diagnostic accuracy of a frozen section.

RESULTS

The patients' median age was 61 years (range, 21-82 years), and most were diagnosed as low-grade appendiceal mucinous neoplasm (LAMN) (84.62%). The diagnostic concordance between the frozen section and the final pathology was 56.92%. The most consistent diagnosis was LAMN (64.14%). Univariate analysis indicated that maximal diameter of the ovarian tumor (unilateral), laterality of the ovarian tumors (unilateral or bilateral), and frozen section site (appendix or extra-appendix) significantly correlated with the accuracy of frozen section diagnosis (all p < 0.05). Although the diagnostic discordance between the frozen section and the final pathology was 43.08%, only one patient was clinically impacted because of suboptimal surgery.

CONCLUSION

Appendiceal mucinous neoplasm should be considered as a differential diagnosis of pelvic mass in women. For patients who do not require fertility-sparing surgery, excision and frozen section of the bilateral ovaries and appendix regardless of the appearance of the appendix might improve the diagnosis. For older patients with peritoneal dissemination, appropriate cytoreductive surgery is recommended to reduce the clinical impact of misdiagnosis.

Efficacy and safety of intraperitoneally administered resveratrol against rat orthotopic ovarian cancers

Background

Resveratrol (Res) inhibits ovarian cancer (OC) cell growth but its in vivo anti-OC effects are unclear due to the low bioavailability of systemically administered Res. Intraperitoneal administration may overcome this therapeutic dilemma because it makes Res directly affect the abdominal tumors. Ethanol and DMSO are common Res solvents, while their reliability and safety for long-term in vivo treatment remain unknown.

Methods

A rat orthotopic OC model was established using the rat NUTU-19 OC cell line. Res dissolved in 10% ethanol or 0.2% DMSO was injected intraperitoneally (20 mg/kg/day) into tumor-free and tumor-bearing rats for 2 weeks. The tumors were collected for gross, morphological and molecular examinations, and blood and ascitic samples were obtained for a CA125 ELISA. Res concentration in ovarian tissues was determined by high performance liquid chromatography (HPLC).

Results

The average tumor weight (0.187±0.065 g) of the Res-in-DMSO group was lower than that of untreated (0.426±0.091 g; P<0.01) and Res-in-ethanol (0.238±0.073 g; P<0.05) group. The average bloody ascitic volumes collected from untreated, Res-in-ethanol, and Res-in-DMSO groups were 5.65±0.27, 2.75±0.14, and 2.09±0.11 ml, respectively. Abundant TUNEL-positive cells, ARHI and PIAS3 upregulation, CA125 reduction, and decreased STAT3 nuclear translocation were found in the Res-in-ethanol and, especially, the Res-in-DMSO group. Widespread plaques of Res deposits were found on the abdominal serosa of the Res-in-ethanol group, but not in the Res-in-DMSO group. HPLC revealed a higher Res concentration in Res-in-DMSO-treated tumor tissues than in those treated by Res-in-ethanol (P<0.01). Fertility was maintained after long-term Res treatment.

Conclusion

Intraperitoneal administration of Res effectively inhibited rat orthotopic ovarian cancer growth without affecting normal tissues. The Res-in-DMSO group had the highest drug bioavailability and therefore stronger tumor-suppressive effects on ovarian cancer tissues.

Epigenetic therapy for ovarian cancer: promise and progress

Ovarian cancer is the deadliest gynecologic malignancy, with a 5-year survival rate of approximately 47%, a number that has remained constant over the past two decades. Early diagnosis improves survival, but unfortunately only 15% of ovarian cancers are diagnosed at an early or localized stage. Most ovarian cancers are epithelial in origin and treatment prioritizes surgery and cytoreduction followed by cytotoxic platinum and taxane chemotherapy. While most tumors will initially respond to this treatment, recurrence is likely to occur within a median of 16 months for patients who present with advanced stage disease. New treatment options separate from traditional chemotherapy that take advantage of advances in understanding of the pathophysiology of ovarian cancer are needed to improve outcomes. Recent work has shown that mutations in genes encoding epigenetic regulators are mutated in ovarian cancer, driving tumorigenesis and resistance to treatment. Several of these epigenetic modifiers have emerged as promising drug targets for ovarian cancer therapy. In this article, we delineate epigenetic abnormalities in ovarian cancer, discuss key scientific advances using epigenetic therapies in preclinical ovarian cancer models, and review ongoing clinical trials utilizing epigenetic therapies in ovarian cancer.

The Evolving Landscape of Chemotherapy in Newly Diagnosed Advanced Epithelial Ovarian Cancer

The treatment of women with advanced-stage epithelial ovarian cancer (EOC) is aggressive surgical cytoreduction and a combination of platinum plus taxane chemotherapy. The timing and extent of surgery has direct implications on the selection of subsequent treatment as well as the prognosis of patients with EOC. Frontline chemotherapeutic regimens have evolved through a series of large multi-institutional randomized clinical trials that focused on targeted agents as maintenance therapy. On June 13, 2018, the U.S. Food and Drug Administration (FDA) approved adding bevacizumab to adjuvant intravenous chemotherapy followed by maintenance based on the results of Gynecologic Oncology Group protocol 218. Maintenance olaparib was FDA-approved on December 19, 2018, for frontline maintenance among those with advanced EOC who respond to frontline chemotherapy and harbor a germline or somatic BRCA1 or BRCA2 mutation. This was based on the results of SOLO-1. Despite a strong rationale and extensive study, intraperitoneal chemotherapy has not been adopted in clinical practice. Alternatively, heated intraperitoneal chemotherapy has shown promise as a more tolerable and technically feasible method of regional therapy, but widespread application will require more evidence. Significant strides have also been made in understanding the biology of EOC, resulting in a personalized approach to first-line therapy. One approach calls for recognizing differences in histologic subtypes and molecular alterations, which may open up alternative therapeutic interventions.

Borderline tumours of the ovary: Common practice in the Netherlands

Objectives

Discordance between frozen section diagnosis and the definite histopathological diagnosis and the fact that the frozen section result is not always unambiguous, may contribute to differences in clinical practice regarding perioperative treatment and follow-up of borderline ovarian tumours (BOTs) patients amongst gynaecologic oncologists, which may lead to over- and undertreatment. The aim of the study was to map the Dutch gynaecologists' preferred treatment and follow-up strategy in case of BOTs.

Methods

A questionnaire was sent to all Dutch gynaecologists involved in ovarian surgery with perioperative frozen section analysis, and the outcomes were assessed using descriptive statistics.

Results

Nearly half of the respondents (41.0%) would not perform a staging procedure in case of a BOT. In case of an ambiguous frozen section diagnosis, tending towards invasive carcinoma, a considerable number (sBOT 56.4%; mBOT 30.8%) would perform a lymph node sampling as part of the staging procedure. A relaparotomy/relaparoscopy, to perform a lymph node sampling in case of a serous or mucinous carcinoma after a BOT frozen section diagnosis, would be performed by 97.4% and 48.7% of the respondents, respectively.

Conclusions

A considerable number of gynaecologists would perform a staging procedure that is recommended for ovarian cancer in case of an ambiguous BOT frozen section diagnosis, especially for serous tumours. In addition, nearly all gynaecologists would perform a second procedure including a lymph node sampling in case of a serous invasive carcinoma after a BOT frozen section diagnosis, which applies to half of the gynaecologists in case of a mucinous carcinoma.

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In case of an unambiguous frozen section BOT diagnosis, a staging procedure is omitted by nearly half of the gynaecologists.

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When the frozen section BOT diagnosis is ambiguous, a full ovarian cancer staging procedure is frequently performed.

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Most gynaecologists perform a second procedure to complete staging when definitive diagnosis shows invasive ovarian cancer.

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Full staging is performed more frequently in case of serous histopathology, when compared to mucinous tumours.