Molecular abnormalities in ovarian carcinoma: clinical, morphological and therapeutic correlates

miR‑146a‑5p and miR‑191‑5p as novel diagnostic marker candidates for ovarian clear cell carcinoma

Ovarian cancer is a malignant gynecologic disease rarely diagnosed in the early stages. Among the various types of ovarian cancer, clear cell carcinoma has a poor prognosis due to its malignant potential. MicroRNAs (miRNAs/miRs) regulate gene expression in cells by suppressing the translation of target genes or by degrading the target mRNA. miRNAs are also secreted from the cells in the blood, binding to proteins or lipids and assisting in cell-cell communication. Therefore, serum miRNAs may be considered potential diagnostic biomarkers for ovarian cancer. The present study investigated and identified specific miRNAs associated with ovarian clear cell carcinoma and compared them to those in ovarian endometrioma samples and healthy controls. CA125, an ovarian tumor marker, did not differ between patients with ovarian clear cell carcinoma, endometriosis or healthy controls. Subsequently, four miRNAs (miR-146a-5p, miR-191-5p, miR-484 and miR-574-3p) were analyzed. The expression levels of miR-146a-5p and miR-191-5p were significantly increased in the serum samples from patients with ovarian clear cell carcinoma compared with those in the healthy controls, but there was no significant difference compared with in patients with endometriosis. Furthermore, the bioinformatics analysis showed that CCND2 and NOTCH2 were the candidate target genes of miR-146a-5p and miR-191-5p. In conclusion, the results of the present study demonstrated that miR-146a-5p and miR-191-5p may be useful as early and non-invasive diagnostic tools in ovarian clear cell carcinoma. These miRNAs can help in distinguishing between ovarian clear cell carcinoma and ovarian endometrioma. To the best of our knowledge, no previous studies have screened any candidates specifically for ovarian clear cell carcinoma.

The role of amphiregulin in ovarian function and disease

Amphiregulin (AREG) is an epidermal growth factor (EGF)-like growth factor that binds exclusively to the EGF receptor (EGFR). Treatment with luteinizing hormone (LH) and/or human chorionic gonadotropin dramatically induces the expression of AREG in the granulosa cells of the preovulatory follicle. In addition, AREG is the most abundant EGFR ligand in human follicular fluid. Therefore, AREG is considered a predominant propagator that mediates LH surge-regulated ovarian functions in an autocrine and/or paracrine manner. In addition to the well-characterized stimulatory effect of LH on AREG expression, recent studies discovered that several local factors and epigenetic modifications participate in the regulation of ovarian AREG expression. Moreover, aberrant expression of AREG has recently been reported to contribute to the pathogenesis of several ovarian diseases, such as ovarian hyperstimulation syndrome, polycystic ovary syndrome, and epithelial ovarian cancer. Furthermore, increasing evidence has elucidated new applications of AREG in assisted reproductive technology. Collectively, these studies highlight the importance of AREG in female reproductive health and disease. Understanding the normal and pathological roles of AREG and elucidating the molecular and cellular mechanisms of AREG regulation of ovarian functions will inform innovative approaches for fertility regulation and the prevention and treatment of ovarian diseases. Therefore, this review summarizes the functional roles of AREG in ovarian function and disease.

Molecular Histopathology for Establishing Diagnostic Method and Clinical Therapy for Ovarian Carcinoma

Ovarian carcinoma (OC) is considered the deadliest gynecological malignancy. It is typically diagnosed in the advanced stages of the disease, with metastatic sites widely disseminated within the abdominal cavity. OC treatment is challenging due to the high rate of disease recurrence, which is further complicated by acquired chemoresistance caused by the reversion of the pathological variant. Therefore, more effective treatments are still being sought. Histologically, OC is classified into serous, mucinous, endometrioid, clear cell, and transitional cell carcinomas and malignant Brenner tumor. Recent clinicopathological and molecular biological studies demonstrated that these subtypes differ in histogenesis and anti-tumor agent sensitivity. In Japan, the incidence rates of the histological types of OC, namely, serous carcinoma, mucinous carcinoma, endometrioid carcinoma, and clear cell adenocarcinoma, are 39%, 12%, 16%, and 23%, respectively. Serous carcinoma is classified as high or low grade, with the former accounting for the overwhelming majority. In this study, the molecular pathological classification of OC has been described based on the characteristics of the two types of OC, types 1 and 2. Compared with Europe and the United States, Japan has a higher prevalence of type 1 OC and a lower prevalence of type 2 OC. The prevalence of each type of OC varies by race. It has been elucidated that the prevalence rate of each type of ovarian cancer in Asian countries is similar to that in Japan. Thus, OC is a heterogeneous disease. Furthermore, OC has been attributed to molecular biological mechanisms that vary among tissue subtypes. Therefore, it is necessary to conduct treatment based on accurate diagnoses of each tissue type and establish an optimal treatment strategy, and now is the transition period.

Nanotechnology-Based Nucleic Acid Vaccines for Treatment of Ovarian Cancer

Anticancer vaccines represent a promising approach for effective treatment of cancer and along with recent advantages of nucleic acid-based vaccines for other diseases form a prospective and potentially efficacious direction of the research, development and clinical applications. Despite the ongoing several clinical trials of mRNA vaccines for the treatment of various types of cancer, to-date no cancer vaccines were approved by the US Food and Drug Administration. The present review analyzes and summarizes major approaches for treating of different forms of ovarian cancer including mRNA-based vaccines as well as nanotechnology-based approaches for their delivery.

Long-term (>5-year) survivors among unresectable or metastatic cancer patients treated with zoledronate-activated killer cells: Seven case reports

We are conducting an adoptive immunotherapy (AIT) trial using zoledronate-activated killer cells for patients in Japan with incurable cancer. We have encountered seven long-term survivors. Since such long survival may be very rare in cancer treatment, we present the details and a discussion of a possible role of AIT.

Clinical Utility of the Geriatric Nutritional Risk Index Before Surgical Intervention for Epithelial Ovarian Cancer Patients: A Retrospective Study

BACKGROUND

The aim of the study is to analyze the impact of the geriatric nutritional risk index (a patient nutritional assessment item) on the prognoses of epithelial ovarian cancer patients.

METHODS

In this retrospective study conducted at a single hospital, we retrospectively analyzed 75 epithelial ovarian cancer patients who underwent surgical treatment at our hospital from 2010 to 2015. The geriatric nutritional risk index cut-off value was calculated using the receiver operating characteristic curve. Patients were divided into two groups on the basis of the calculated value. Kaplan-Meier curves were prepared for each group, and the difference in survival rates was calculated using the log-rank test. Cox proportional hazards regression analysis was used to compare other factors that affect prognosis.

RESULTS

The geriatric nutritional risk index was calculated to be 97.3. The survival rate was 61.9% for the group of patients with an index value > 97.3, and 39.4% for patients with an index value < 97.3 at 48 months (P < 0.001). A univariate analysis was performed with the following variables: age > 60 years, albumin level < 3.5 g/dL, body mass index < 22, presence of ascites, cancer antigen 125 level > 35 U/mL, type of tumor tissue, residual lesion, and geriatric nutritional risk index < 97.3. Albumin level, residual lesion, and geriatric nutritional risk index showed significant differences. A multivariate analysis was also performed, and only the geriatric nutritional risk index showed a significant difference (P = 0.0481).

CONCLUSIONS

The geriatric nutritional risk index may have a strong influence on the prognoses of epithelial ovarian cancer patients. We recommend utilizing these findings in daily clinical practice and incorporating them into treatment strategies for epithelial ovarian cancer.

Exosomal MicroRNA as Biomarkers for Diagnosing or Monitoring the Progression of Ovarian Clear Cell Carcinoma: A Pilot Study

Ovarian cancer is the most common cause of gynecological malignancy-related mortality since early-stage disease is difficult to diagnose. Advanced clear cell carcinoma of the ovary (CCCO) has dismal prognosis, and its incidence has been increasing in Japan, emphasizing the need for highly sensitive diagnostic and prognostic CCCO biomarkers. Exosomal microRNAs (miRNAs) secreted by tumor cells are known to play a role in carcinogenesis; however, their involvement in ovarian cancer is unclear. In this study, we performed expression profiling of miRNAs from exosomes released by five cell lines representing different histological types of ovarian cancer. Exosomes isolated from culture media of cancer and normal cells were compared for miRNA composition using human miRNA microarray. We detected 143 exosomal miRNAs, whose expression was ≥1.5-fold higher in ovarian cancer cells than in the control. Among them, 28 miRNAs were upregulated in cells of all histological ovarian cancer types compared to control, and three were upregulated in CCCO cells compared to other types. Functional analyses indicated that miR-21 overexpressed in CCCO cells targeted tumor suppressor genes PTEN, TPM1, PDCD4, and MASP1. The identified miRNAs could represent novel candidate biomarkers to diagnose or monitor progression of ovarian cancer, particularly CCCO.

Key changes to the world health organisation (who) classification of female genital tumours introduced in the 5TH edition (2020)

An updated World Health Organisation (WHO) Classification of Female Genital Tumours was published in Autumn 2020. We discuss the major new additions and changes from the prior 2014 Classification with discussion of the reasons underlying these. A feature of the new Classification is the greater emphasis on key molecular events with integration of morphological and-molecular features. Most of the major changes from the prior Classification pertain to uterine (corpus and cervix) and vulval tumours but changes in all organs are covered.

Intraperitoneal Administration of a Cisplatin-Loaded Nanogel through a Hybrid System Containing an Alginic Acid-Based Nanogel and an In Situ Cross-Linkable Hydrogel for Peritoneal Dissemination of Ovarian Cancer

Intraperitoneal chemotherapy demonstrates potential applicability in the treatment of peritoneally disseminated ovarian cancer because the disseminated tumors can directly receive exposure to high concentrations of anticancer drugs. However, a considerable proportion of drugs, particularly micromolecular and hydrophilic drugs, such as cisplatin (CDDP), are often excreted through glomerular filtration for a short period. To effectively deliver CDDP into peritoneally disseminated ovarian cancer tissues, we developed an alginate (AL)-based hybrid system in which a CDDP-loaded AL nanogel (AL/CDDP-nanogel) was encapsulated in an injectable AL-hydrogel cross-linked with calcium ions. This system enabled the sustained release of CDDP from the AL/CDDP-nanogel/AL-hydrogel hybrid for over a week. Herein, we constructed a peritoneally disseminated ovarian cancer mouse model using ovarian cancer cell lines with KRAS mutations (ID8-KRAS: KRAS^G12V). The AL/CDDP-nanogel/AL-hydrogel hybrid system showed significant antitumor activity in vivo. This therapy may be considered a novel strategy for the treatment of advanced-stage ovarian cancer with KRAS mutations.

A DNA Damage Response Gene Panel for Different Histologic Types of Epithelial Ovarian Carcinomas and Their Outcomes

DNA damage response (DDR) is important for maintaining genomic integrity of the cell. Aberrant DDR pathways lead to accumulation of DNA damage, genomic instability and malignant transformations. Gene mutations have been proven to be associated with epithelial ovarian cancer, and the majority of the literature has focused on BRCA. In this study, we investigated the somatic mutation of DNA damage response genes in epithelial ovarian cancer patients using a multiple-gene panel with next-generation sequencing. In all, 69 serous, 39 endometrioid and 64 clear cell carcinoma patients were enrolled. Serous carcinoma patients (69.6%) had higher percentages of DDR gene mutations compared with patients with endometrioid (33.3%) and clear cell carcinoma (26.6%) (p < 0.001, chi-squared test). The percentages of DDR gene mutations in patients with recurrence (53.9 vs. 32.9% p = 0.006, chi-squared test) or cancer-related death (59.2 vs. 34.4% p = 0.001, chi-squared test) were higher than those without recurrence or living patients. In endometrioid carcinoma, patients with ≥2 DDR gene mutations had shorter PFS (p = 0.0035, log-rank test) and OS (p = 0.015, log-rank test) than those with one mutation or none. In clear cell carcinoma, patients with ≥2 DDR gene mutations had significantly shorter PFS (p = 0.0056, log-rank test) and OS (p = 0.0046, log-rank test) than those with 1 DDR mutation or none. In the EOC patients, somatic DDR gene mutations were associated with advanced-stage tumor recurrence and tumor-related death. Type I EOC patients with DDR mutations had an unfavorable prognosis, especially for clear cell carcinoma.

Decreased Gastric Gland Mucin-specific O-glycans Are Involved in the Progression of Ovarian Primary Mucinous Tumours

Ovarian primary mucinous tumours (OPMTs) show an adenoma–borderline–carcinoma sequence with gastrointestinal metaplasia. Gastric gland mucin-specific O-glycans are unique with an α1,4-linked N-acetylglucosamine (αGlcNAc) residue attached to mucin 6 (MUC6). Although αGlcNAc is expected to be expressed in OPMTs, the relationship between αGlcNAc expression and OPMT progression remains unknown. Here, we analysed 104 areas of benign mucinous tumours (benign), 55 areas of borderline mucinous tumours (borderline), and 18 areas of malignant mucinous tumours (malignant) to investigate the expression patterns of αGlcNAc, mucin 2 (MUC2), mucin 5AC (MUC5AC), and MUC6 during the progression of OPMT from benign to malignant. MUC5AC expression was observed in all areas. The frequencies of MUC6- and αGlcNAc-positive areas were decreased with tumour progression. In particular, the decrease in αGlcNAc-positive areas was remarkable. Furthermore, αGlcNAc expression was lower than MUC6 expression at all grades (benign, p < 0.0001; borderline, p = 0.0014; malignant, p = 0.0039). Conversely, there was no difference in the expression frequency or level of MUC2 among the three grades. These results suggest that decreased expression of αGlcNAc relative to MUC6 occurs early in tumour development and marks the initiation of OPMT progression.

Potential Novel Ovarian Cancer Treatment Targeting Myeloid-Derived Suppressor Cells

Diagnosis by biopsy is difficult in the ovary since it is located deep in the abdomen. As a result, ovarian cancer is mostly found insidiously during exploratory laparotomy. Consequently, the early diagnosis of ovarian cancer is often difficult. The likelihood of peritoneal dissemination increases with the progress of ovarian cancer. With further progression, ovarian cancer metastasizes to the momentum, retroperitoneal lymph nodes, large intestine, small intestine, diaphragm, spleen, and other organs. Ovarian cancer has been considered a tumor that has a favorable response to chemotherapy, but more effective treatments are still being explored. Tumors use their own immune escape mechanism to evade host immunity. The immune checkpoint (IC) mechanism, one of the immune escape mechanisms, is established by programmed cell death-1 (PD-1)/PD-ligand-1 (PD-L1) communication. It has been shown that inhibiting PD-1/PD-L1 communication in various malignancies produces antitumor effects. However, the antitumor effect of ICI monotherapy on ovarian cancer is limited in actual clinical practice. In this review, we describe a novel cancer immunotherapeutic agent that targets myeloid-derived suppressor cells (MDSCs).

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.

Apparent diffusion coefficient (ADC) values of serous, endometrioid, and clear cell carcinoma of the ovary: pathological correlation

BACKGROUND

Primary epithelial ovarian cancer is divided into several subtypes. The relationships between apparent diffusion coefficient (ADC) values and their subtypes have not yet been established.

PURPOSE

To investigate whether ADC values of epithelial ovarian cancer vary according to histologic tumor cellularity and evaluate the difference of clear cell carcinoma (CCC), high-grade serous carcinoma (HGSC), and endometrioid carcinoma (EC).

MATERIAL AND METHODS

This retrospective study included 51 cases of epithelial ovarian cancer (17 CCC, 20 HGSC, and 14 EC) identified by magnetic resonance imaging with pathological confirmation. All patients underwent diffusion-weighted imaging and the ADC values of lesions were measured. We counted the tumor cells in three high-power fields and calculated the average for each case. The Spearman's correlation coefficient test was used to analyze correlation between ADC values and tumor cellularity. The ADC values of HGSC, EC, and CCC were compared using the Steel-Dwass test.

RESULTS

The ADC values of all cases were significantly inversely correlated with tumor cellularity (r_s = -0.761; P < 0.001). The mean ± SD ADC values (×10^-3 mm²/s) of CCC, HGSC, and EC were 1.24 ± 0.17 (range 0.98--1.65), 0.84 ± 0.10 (range 0.67--1.06), and 0.84 ± 0.10 (range 0.67--1.07). The mean ± SD tumor cellularity of CCC, HGSC, and EC was 162.88 ± 63.28 (range 90.33--305.67), 440.60 ± 119.86 (range 204.67--655.67), and 461.02 ± 81.86 (range 333.33--602.33).

CONCLUSION

There is a significant inverse correlation between ADC values and tumor cellularity in epithelial ovarian cancer. The mean ADC value of CCC was higher than those of HGSC and EC, seemingly due to the low cellularity of CCC.

In vivo modeling of metastatic human high-grade serous ovarian cancer in mice

Metastasis is responsible for 90% of human cancer mortality, yet it remains a challenge to model human cancer metastasis in vivo. Here we describe mouse models of high-grade serous ovarian cancer, also known as high-grade serous carcinoma (HGSC), the most common and deadliest human ovarian cancer type. Mice genetically engineered to harbor Dicer1 and Pten inactivation and mutant p53 robustly replicate the peritoneal metastases of human HGSC with complete penetrance. Arising from the fallopian tube, tumors spread to the ovary and metastasize throughout the pelvic and peritoneal cavities, invariably inducing hemorrhagic ascites. Widespread and abundant peritoneal metastases ultimately cause mouse deaths (100%). Besides the phenotypic and histopathological similarities, mouse HGSCs also display marked chromosomal instability, impaired DNA repair, and chemosensitivity. Faithfully recapitulating the clinical metastases as well as molecular and genomic features of human HGSC, this murine model will be valuable for elucidating the mechanisms underlying the development and progression of metastatic ovarian cancer and also for evaluating potential therapies.

Rarely does an experimental model fully replicate the clinical metastases of a human malignancy. Faithfully representing the clinical metastases of human high-grade serous ovarian cancer with complete penetrance, coupled with histopathological, molecular, and genomic similarities, these mouse models, particularly one harboring mutant p53, will be vital to elucidating the underlying pathogenesis of human ovarian cancer. In-depth understanding of the development and progression of ovarian cancer is crucial to medical advances in the early detection, effective treatment, and prevention of ovarian cancer. Also, these robust mouse models, as well as cell lines established from the mouse primary and metastatic tumors, will serve as useful preclinical tools to evaluate therapeutic target genes and new therapies in ovarian cancer.

Synergistic effect of the inhibitors of RAF/MEK and AXL on KRAS-mutated ovarian cancer cells with high AXL expression

KRAS mutation is frequently seen in a subtype of ovarian cancer categorized as type 1. The KRAS-MAPK pathway, which is closely involved in type 1 cancer progression, is under the regulation of receptor tyrosine kinases (RTKs). AXL, one of the RTKs, has been reported to be overexpressed in ovarian cancer and contributes to the poor prognosis. However, there is no useful target-based agent against such gene profiles. We examined the combined effect of the dual RAF/MEK inhibitor CH5126766 and AXL inhibitor R428 on the growth of ovarian cancer HEY-T30 and OVCAR-5 cell lines, both of which bear KRAS mutation and express AXL at a high level, using the WST-8 assay and the colony formation assay. The synergistic effect of the combination was evaluated by the combination index. The apoptotic cells were analyzed by flow cytometry. The expression of apoptotic proteins and the phosphorylation of MAPK and AKT pathway proteins were investigated by western blotting. We found that CH5126766 and R428 suppressed the phosphorylation of ERK and AKT, respectively, and their combination synergistically inhibited the growth of both cell lines with enhancement of apoptosis accompanied by the Bim upregulation. Combined treatment with CH5126766 and R428 is expected as the novel therapeutic option for KRAS-mutated ovarian cancer with high expression of AXL.

The Preoperative Prognostic Nutritional Index for the Prediction of Outcomes in Patients with Early-Stage Ovarian Clear Cell Carcinoma

The prognostic nutritional index (PNI), which reflects preoperative malnutrition, is useful for predicting the incidence of postoperative complications and has been reported in recent years to predict the long-term prognosis of various malignancies. The purpose of this study was to clarify the significance of PNI as a prognostic factor for early-stage clear cell ovarian carcinoma. A total of 82 patients with stage I-II (FIGO 2014) ovarian clear cell carcinoma undergoing primary surgery at our hospital from January 2005 to December 2017 were enrolled. PNI was calculated using the formula: 10 × serum albumin (g/ dL) + 0.005 × peripheral blood lymphocyte count (/mm3). Preoperative PNI exhibited relatively high area under the curve value (0.709) for 5 year survival, and the optimal cutoff value was 46.5. The overall survival was significantly shorter in the PNI-low group than in the PNI-high group. Multivariate analysis showed that high PNI was a significant independent prognostic factor for favorable prognosis (hazard ratio = 0.102, p = 0.010). There was no significant difference in recurrence-free survival between the two groups (p = 0.220), but the postrecurrence survival was significantly longer in the PNI-high group than in the PNI-low group (p = 0.0383). The preoperative PNI was a useful predictor of prognosis, even in early-stage ovarian clear cell carcinoma.

Identification of novel mutations of ovarian cancer-related genes from RNA-sequencing data for Japanese epithelial ovarian cancer patients

Ovarian cancer has the highest mortality rate among gynecological cancers. Gene mutations are involved in the carcinogenesis, metastasis, and therapeutic response in ovarian cancer. However, the variety and proportion of gene mutation is not fully analyzed in Japanese ovarian cancer patients, especially, in those with recurrent tumors. In the present study, RNA-sequencing was performed for 32 clinical ovarian specimens obtained from 24 Japanese patients (24 primary cancer specimens and 8 recurrent specimens paired with corresponding primary cancer specimens). Mutations in 24 primary specimens were analyzed by comparing the sequence data mapped on RefSeq genes with those in the public online databases BRCA Exchange, COSMIC, ClinVar, and cBioportal. Mutations were observed in TP53 in 16 specimens (67%), BRCA1 in 9 (38%), BRCA2 in 13 (54%), ARID1A in 3 (13%), PIK3CA in 2 (8%), KRAS in 1 (4%), PTEN in 1 (4%), and CTNNB1 in 1 (4%), excluding synonymous mutations. Among those identified muations, 13 of 14 mutations in TP53, 10 of 11 mutations of BRCA1, 10 of 23 mutation positions of BRCA2, none of 7 mutations of ARID1A, 1 mutation of PIK3CA, and 1 mutation of CTNNB1 were consistent with those reported in the public online databases; however, the other mutations identified were novel. Comparison between matched-paired specimens of primary and recurrent tumors revealed the changes of mutational status in expressed RNAs. RNA-sequencing-based mutation analysis will be useful to reveal ethnic differences of gene mutations in ovarian cancer and to understand the contribution of gene mutations to recurrence.

Debulking surgery for colorectal liver metastases: Foolish or chance?

Even with the recent advances of surgical techniques and systemic therapies, we are often facing patients with multinodular bilateral disease for whom neither R0 nor R1 resection appears possible to perform. For such extensive cases, the tumor debulking approaches might provide a survival benefit, provided that an objective tumor response is obtained with chemotherapy. Here, we review all the arguments which may defend this strategy and propose some recommendations.

Extragonadal Giant Endometrial Cyst with Endometrioid Borderline Tumor

We describe an extremely rare case of a borderline tumor arising from an extragonadal giant endometrial cyst. A 41-year-old woman complaining of abdominal pain was referred to our hospital with a diagnosis of large ovarian tumor. Magnetic resonance imaging revealed a large cystic tumor approximately 27 cm × 9 cm in area. The cyst contents were largely removed by suction, and then the tumor was resected laparoscopically. Both adnexa were normal in size and location. The tumor did not originate from the ovaries, and it was adherent only to the bilateral uterosacral ligaments and uterine body. The postoperative histopathological evaluation confirmed the presence of endometrioid borderline tumor with transition from endometriosis. Staging laparotomy was performed, and no remnant tumor was detected. This case is extremely unusual because such a large cystic tumor originating from extragonadal endometriosis is very rare, as is endometrioid borderline tumor arising from endometriosis.

Relationship between Microsatellite Instability, Immune Cells Infiltration, and Expression of Immune Checkpoint Molecules in Ovarian Carcinoma: Immunotherapeutic Strategies for the Future

Ovarian cancer has the worst prognosis among gynecological cancers. Thus, new ovarian cancer treatment strategies are needed. Currently, immune checkpoint inhibitors such as anti-PD-1/PD-L1 antibody are attracting attention worldwide. The Food and Drug Administration approved the use of the PD-1 antibody pembrolizumab for solid cancers with microsatellite instability (MSI)-H or mismatch repair (MMR) deficiency in 2017. However, few studies on ovarian carcinoma have evaluated the relationship among MSI status, lymphocyte infiltration into the tumor, and the expression of immune checkpoint molecules by histologic type. We evaluated the expression of MMR proteins, tumor-infiltrating lymphocytes (CD8+), and immune checkpoint molecules (PD-L1/PD-1) by immunohistochemistry in 136 ovarian cancer patients (76, 13, 23, and 24 cases were high-grade serous, mucinous, endometrioid, and clear cell carcinoma, respectively) to investigate the effectiveness of immune checkpoint inhibitors. Only six cases (4.4%) had loss of MMR protein expression. There was no significant relationship between MSI status and age (p = 0.496), FIGO stage (p = 0.357), initial treatment (primary debulking surgery [PDS] or neoadjuvant chemotherapy) (p = 0.419), residual tumor after PDS or interval debulking surgery (p = 0.202), and expression of CD8 (p = 0.126), PD-L1 (p = 0.432), and PD-1 (p = 0.653). These results suggest that only a small number of MSI cases in ovarian cancer can be effectively treated with immune checkpoint inhibitor monotherapy. Therefore, to improve the prognosis of ovarian carcinoma, a combination therapy of immune checkpoint inhibitors and other anticancer drugs is necessary.

Systematic Identification of Characteristic Genes of Ovarian Clear Cell Carcinoma Compared with High-Grade Serous Carcinoma Based on RNA-Sequencing

Objective: Ovarian cancer has the highest mortality among gynecological cancers. High-grade serous carcinoma (HGSC) is the most common histotype of ovarian cancer regardless of ethnicity, whereas clear cell carcinoma (CCC) is more common in East Asians than Caucasians. The elucidation of predominant signaling pathways in these cancers is the first step towards understanding their molecular mechanisms and developing their clinical management. Methods: RNA sequencing was performed for 27 clinical ovarian specimens from Japanese women. Principal component analysis (PCA) was conducted on the sequence data mapped on RefSeq with normalized read counts, and functional annotation analysis was performed on genes with substantial weights in PCA. Knockdown experiments were conducted on the selected genes on the basis of PCA. Results: Functional annotation analysis of PCA-defined genes showed predominant pathways, such as cell growth regulators and blood coagulators in CCC and transcription regulators in HGSC. Knockdown experiments showed that the inhibition of the calcium-dependent protein copine 8 (CPNE8) and the transcription factor basic helix-loop-helix family member e 41 (BHLHE41) repressed the proliferation of CCC- and HGSC-derived cells, respectively. Conclusions: This study identified CPNE8 and BHLHE41 as characteristic genes for CCC and HGSC, respectively. The systemic identification of differentially expressed genes in CCC and HGSC will provide useful information to understand transcriptomic differences in these ovarian cancers and to further develop potential diagnostic and therapeutic options for advanced disease.

Peritoneal involvement by salpingoliths clinical significance and cytological challenges of interpretation

We present a case of salpingoliths detected in peritoneal washing, during an elective bilateral salpingo-oophorectomy, in a 32 years old woman with history of familial BRCA gene mutation. Salpingoliths are psammoma body-like types of calcification that originate from the fallopian tubes and can be encountered in peritoneal washings. Unlike psammoma bodies, salpingoliths have been tagged to benign and hyperplastic processes more often than neoplastic processes. Misinterpreting salpingoliths as psammoma bodies in peritoneal washings can be misleading for both cytopathologists and clinicians, especially as in the presented case, where there is a high risk for ovarian carcinoma. In this article, we aim to shed light on this rare finding, and report theories explaining its pathogenesis, in addition we provide an example of its challenging cytological presentation, to increase awareness among cytopathologists.

ADP-ribosylation factor-like 4C predicts worse prognosis in endometriosis-associated ovarian cancers

BACKGROUND

Endometrioid ovarian carcinoma and clear cell ovarian carcinoma are both classified as endometriosis-associated ovarian cancer (EAOC). Despite the high rates of recurrence and mortality of EAOC, no prognostic biomarkers have been determined. ADP-ribosylation factor-like protein 4C (ARL4C) has been reported to be involved in various tumor progression processes, but its clinical significance for predicting prognosis in EAOC cases has never been studied.

OBJECTIVE

The present study aimed to determine the clinical significance of ARL4C expression in EAOC prognosis.

METHODS

ARL4C expression was semi-quantitatively evaluated via immunohistochemistry in 61 EAOC patients, and the correlations between ARL4C expression and clinicopathological data and survival were statistically analyzed.

RESULTS

Thirty-six (59%) cases had high levels of ARL4C, which was related to worse 5-year overall survival (OS) (log-rank test, p= 0.036). In multivariate Cox proportional hazard model, high ARL4C expression was a significantly independent predictive factor for worse 5-year OS (hazard ratio = 12.048, p= 0.0201) and 5-year PFS (hazard ratio = 8.130, p= 0.0036).

CONCLUSIONS

ARL4C is a biomarker for worse prognosis and a novel therapeutic target in EAOC.

RAS Mutation in Mucinous Carcinoma of the Ovary

Objective: This study was designed to identify genetic mutation in mucinous carcinoma of the ovary of the patients in King Chulalongkorn Memorial hospital, Bangkok, Thailand and study the relationship between genetic mutation and patients’ prognosis. Methods: Fifty cases of primary mucinous carcinoma of the ovary were selected. DNA was analyzed for genetic mutation using ColoCarta Panel v1.0 and MassArray® System. Demographic data and clinical information of the participants were reviewed from electronic medical records and government data services. Results: Median of disease-free survival is 171.33 +/- 9.04 months and the median overall survival is 171.37 +/- 9.03 months. Twelve percent of the participants had recurrence and all of recurrent cases died from disease or its complication. We found three mutations which were KRAS (27 cases, 54%), PIK3CA (4 cases, 8%) and BRAF (1 case, 2%). Among the KRAS-mutated patients, the majority of the cases (25 cases, 92.6%) were in stage I. Recurrence and disease related mortality were not observed in the KRAS mutated patients. Conclusion: The genetic mutation analysis found three mutations which were KRAS 27 cases (54%), PIK3CA 4 cases (8%) and BRAF 1 case (2%) The ovarian mucinous carcinoma patients with KRAS mutation in our study showed excellent prognosis.

Evaluation of lysophosphatidic acid in vaginal fluid as a biomarker for ovarian cancer: A pilot study

There remains a need to differentiate between women with a benign or a malignant adnexal mass prior to surgery. As part of an ongoing evaluation of vaginal fluid compounds as potential tumor biomarkers we evaluated whether vaginal lysophosphatidic acid (LPA) predicted the subsequent diagnosis of a malignant adnexal mass. In this prospective pilot study vaginal fluid was obtained from 100 post-menopausal women referred for evaluation of a suspicious adnexal mass and tested for LPA by ELISA. Clinical data and serum CA125 results were obtained only after completion of all laboratory testing. Twenty eight of the women were subsequently diagnosed with an ovarian malignancy, four had a borderline tumor and 68 had a benign diagnosis. Among women with a malignant ovarian mass, 11 (39.3%) had an endometrioid adenocarcinoma +/− Clear cell tumor components, 6 (21.4%) had a high grade serous carcinoma, 3 (10.7%) had a mucinous tumor, 2 each (7.1%) had a malignant mixed mesodermal or a granulosa tumor and 1 each (3.6%) had a Clear cell tumor, a mixed cell tumor, leimyosarcoma or metastatic adrenal tumor. Compared to the median vaginal LPA level in women with benign lesions (1.5 μM), LPA was significantly elevated only in women with endometrioid ovarian cancer (7.9 μM) (p = 0.0137). Of the 6 endometrioid tumors in which values for both plasma CA125 and vaginal LPA were available 5 were positive only for LPA while one was only CA125 positive. Detection of LPA in vaginal secretions may be of value for the noninvasive diagnosis of endometrioid ovarian malignancies in post-menopausal women.

Cell Origins of High-Grade Serous Ovarian Cancer

High-grade serous ovarian cancer, also known as high-grade serous carcinoma (HGSC), is the most common and deadliest type of ovarian cancer. HGSC appears to arise from the ovary, fallopian tube, or peritoneum. As most HGSC cases present with widespread peritoneal metastases, it is often not clear where HGSC truly originates. Traditionally, the ovarian surface epithelium (OSE) was long believed to be the origin of HGSC. Since the late 1990s, the fallopian tube epithelium has emerged as a potential primary origin of HGSC. Particularly, serous tubal intraepithelial carcinoma (STIC), a noninvasive tumor lesion formed preferentially in the distal fallopian tube epithelium, was proposed as a precursor for HGSC. It was hypothesized that STIC lesions would progress, over time, to malignant and metastatic HGSC, arising from the fallopian tube or after implanting on the ovary or peritoneum. Many clinical studies and several mouse models support the fallopian tube STIC origin of HGSC. Current evidence indicates that STIC may serve as a precursor for HGSC in high-risk women carrying germline BRCA1 or 2 mutations. Yet not all STIC lesions appear to progress to clinical HGSCs, nor would all HGSCs arise from STIC lesions, even in high-risk women. Moreover, the clinical importance of STIC remains less clear in women in the general population, in which 85–90% of all HGSCs arise. Recently, increasing attention has been brought to the possibility that many potential precursor or premalignant lesions, though composed of microscopically—and genetically—cancerous cells, do not advance to malignant tumors or lethal malignancies. Hence, rigorous causal evidence would be crucial to establish that STIC is a bona fide premalignant lesion for metastatic HGSC. While not all STICs may transform into malignant tumors, these lesions are clearly associated with increased risk for HGSC. Identification of the molecular characteristics of STICs that predict their malignant potential and clinical behavior would bolster the clinical importance of STIC. Also, as STIC lesions alone cannot account for all HGSCs, other potential cellular origins of HGSC need to be investigated. The fallopian tube stroma in mice, for instance, has been shown to be capable of giving rise to metastatic HGSC, which faithfully recapitulates the clinical behavior and molecular aspect of human HGSC. Elucidating the precise cell(s) of origin of HGSC will be critical for improving the early detection and prevention of ovarian cancer, ultimately reducing ovarian cancer mortality.

A Pathological Study Using 2014 WHO Criteria Reveals Poor Prognosis of Grade 3 Ovarian Endometrioid Carcinomas

BACKGROUND/AIM

The purpose of this study was to compare the clinical behavior of several grades of endometrioid carcinoma (EC) compared to high-grade serous carcinoma (HGSC), based on World Health Organization 2014 criteria.

MATERIALS AND METHODS

Clinicopathological features were compared between all grades of EC and HGSC, and between HGSC and either grade 1/2 or grade 3 EC.

RESULTS

Sixty-five patients with EC and 214 with HGSC were identified. Among patients with EC, 56 displayed 1/2 EC and nine had grade 3 EC. The progression-free (PFS) and overall (OS) survival of patients with grade 1/2 EC were better than of those of patients with HGSC; however, PFS and OS did not statistically differ between patients with grade 3 EC and those with HGSC. Grade 1/2 EC, but not grade 3, was a better prognostic factor compared with HGSC.

CONCLUSION

A grading system for EC would be beneficial for the accurate prognosis of ovarian cancer.

Comparative study of endometrioid borderline ovarian tumor with and without endometriosis

Background

Synchronous endometriosis has been poorly studied in women with endometrioid borderline ovarian tumors (EBOTs). The aims of this study were to compare the clinicopathological features and prognosis of EBOTs with or without endometriosis.

Results

Of 52 patients diagnosed with EBOTs, no death was observed and only one case had successful pregnancy during the follow-up period. Older, menopausal EBOT patients, EBOT patients with small tumors and relatively low CA125 level probably had better progression-free survival (PFS) outcomes. About 1/3 of EBOTs had concomitant endometrial lesions. Approximately 1/3 of EBOTs were associated with endometriosis. Patients were divided into two groups according to the presence or not of endometriosis in this retrospective cohort study. Patients with endometriosis-associated endometrioid borderline ovarian tumor (EAEBOT) were more likely to be younger and premenopausal. Variables such as PFS outcomes, endometrial lesions did not differ statistically between groups. However, in specific EBOT patients like parous patients, patients with CA125 ≥ 140 U/ml or patients without fertility sparing surgery, coexisting endometriosis perhaps predicted worse PFS outcomes.

Conclusion

We considered EAEBOT as an entity similar to non-EAEBOT. Closely follow-up for some particular patients with concomitant endometriosis was necessary.

Preclinical Models of Ovarian Cancer: Pathogenesis, Problems, and Implications for Prevention

Preclinical models are relatively underutilized and underfunded resources for modeling the pathogenesis and prevention of ovarian cancers. Several reviews have detailed the numerous published models of ovarian cancer. In this review, we will provide an overview of experimental model systems, their strengths and limitations, and use selected models to illustrate how they can be used to address specific issues about ovarian cancer pathogenesis. We will then highlight some of the preclinical prevention studies performed to date and discuss experiments needed to address important unanswered questions about ovarian cancer prevention strategies.

An update on the use of immunohistochemistry and molecular pathology in the diagnosis of pre-invasive and malignant lesions in gynecological oncology

OBJECTIVE

One of the most common challenges in everyday clinical practice of gynecological oncology is to identify the type and the primary origin of a tumor. This is a crucial step in the management, treatment, prognosis, and survival of patients suffering from a gynecological malignancy. Immunohistochemistry has been widely adopted over the last three decades in pathology laboratories all over the world. Recent advances in our understanding of the differentiation of gynecological tumors based on immunohistochemical expression have resulted in use of immunohistochemistry as a major diagnostic tool in gynecology, for precise tumor classification. More recently, advances in molecular pathology, have taken this disease sub-classification further resulting in more effective personalised treatment regimens. The aim of this review is to provide clinicians with up to date information on the various immunohistochemical and molecular tests used in the diagnosis of gynecological malignancies of the female genital tract and an understanding of how to interpret them.

METHODS

We performed a review of the current literature including review articles, original research articles, and guidelines on various immunohistochemical markers and molecular techniques which are used for the differential diagnosis of gynecologic malignancies.

CONCLUSIONS

Immunohistochemistry is useful as an objective means for improved diagnostic reproducibility, accuracy, and precise classification in cases where the diagnosis with histochemical stains is inconclusive, providing a more reliable estimate of clinical outcomes. The diagnosis, in some cases, can be further refined by the use of molecular techniques leading to personalised medical treatments.

Mutational Aberrations Detected in Mucinous Epithelial Ovarian Cancer of Asian Women

BACKGROUND

Mucinous epithelial ovarian cancers (mEOCs) respond poorly to conventional chemotherapy and have a poor prognosis in advanced stages. The genomic landscape for mEOC in the Asian settings is ill defined. We seek to identify various mutational aberrations present in mEOC and correlate them with clinical outcomes.

METHODS

A total of 199 cases of mEOC were identified from a prospectively maintained gynecologic oncology tumor database. DNA was extracted and analyzed for KRAS mutations by using Sanger sequencing. Further MassArray sequencing was performed on 45 samples. Clinicopathologic correlation was performed with the results obtained.

FINDINGS

KRAS mutation status was evaluable in 124 cases. Fifty-five percent (68/124) were KRAS negative, whereas 45% (56/124) harbored a KRAS mutation, lower than that in Western populations. Successful ascertainment of both KRAS and HER2 statuses by Sanger sequencing occurred for 105 cases. The proportion of the double-positive subtype (HER2+ and KRAS positive) was 8% (8/105); double-negative subtype (HER2- and KRAS negative), 34% (36/105); and cases with mutation in either KRAS or HER2, 58% (61/105). The KRAS mutation rate was 44%, 50%, and 29% among Chinese, Indians, and Malays, respectively. There was no significant difference in overall survival (P = 0.952) or progression-free survival (P = 0.635) between KRAS-positive and KRAS-negative patients. Similar results were observed for progression-free survival (P = 0.206) and overall survival (P = 0.440) when outcomes were examined between the 4 groups based on KRAS and HER2 mutation. Patients in the double-negative mutation subgroup had higher risk for death/progression compared with patients in the other 3 mutation subgroups. Further MassARRAY multiplexed profiling was performed in patients with sufficient DNA material (n = 45) and yielded KRAS mutations (n = 16), PDGFRA mutations (n = 3), PIK3CA (n = 1) and KIT (n = 1), and HRAS, FGFR, MET, and NRAS (n = 1 each).

CONCLUSIONS

Our study provides further knowledge about the mutational aberrations in mEOC in Asian populations. Neither the presence of KRAS mutation nor their correlation with HER2 mutations influenced outcomes.

Endometriosis-associated ovarian neoplasia

This article reviews the most relevant pathological and molecular features of ovarian tumours that are associated with endometriosis. Endometriosis is a common condition, affecting 5-15% of all women, and it has been estimated that 0.5-1% of cases are complicated by neoplasia. The most common malignant tumours in this setting are endometrioid adenocarcinoma and clear cell adenocarcinoma, each accounting for approximately 10% of ovarian carcinomas in Western countries. A minority of cases are associated with Lynch syndrome. These carcinomas are often confined to the ovaries at presentation in which case they have relatively favourable outcomes. However, high-stage tumours, particularly clear cell carcinomas, generally have a poor prognosis and this partly reflects relative resistance to current treatment. Histological diagnosis is straightforward in the majority of cases but some variants, for example endometrioid carcinomas with sex cord-like appearances or oxyphil cells, may create diagnostic difficulty. Similarly, clear cell carcinomas can show a range of architectural and cytological patterns that overlap with other tumours, both primary and metastatic, involving the ovaries. Endometriosis-associated borderline tumours are less common, and they often show mixed patterns of differentiation (seromucinous tumours). Atypical endometriosis may represent an intermediate step in neoplastic progression and some of these lesions demonstrate immunohistological and molecular alterations similar to those observed in endometriosis-related tumours. ARID1A mutations are relatively common in all of these tumours, but each has additional characteristic molecular alterations which are likely to be of increasing clinical relevance as targeted therapies are developed. Less is known of the pathogenesis of rarer endometriosis-associated ovarian tumours including endometrioid stromal sarcoma, mesodermal (Müllerian) adenosarcoma, and carcinosarcoma. This article also briefly reviews the issue of synchronous endometrioid carcinomas of the endometrium and the ovary, including the most recent developments on pathogenesis.

Phosphoproteomics of Primary Cells Reveals Druggable Kinase Signatures in Ovarian Cancer

Our understanding of the molecular determinants of cancer is still inadequate because of cancer heterogeneity. Here, using epithelial ovarian cancer (EOC) as a model system, we analyzed a minute amount of patient-derived epithelial cells from either healthy or cancerous tissues by single-shot mass-spectrometry-based phosphoproteomics. Using a multi-disciplinary approach, we demonstrated that primary cells recapitulate tissue complexity and represent a valuable source of differentially expressed proteins and phosphorylation sites that discriminate cancer from healthy cells. Furthermore, we uncovered kinase signatures associated with EOC. In particular, CDK7 targets were characterized in both EOC primary cells and ovarian cancer cell lines. We showed that CDK7 controls cell proliferation and that pharmacological inhibition of CDK7 selectively represses EOC cell proliferation. Our approach defines the molecular landscape of EOC, paving the way for efficient therapeutic approaches for patients. Finally, we highlight the potential of phosphoproteomics to identify clinically relevant and druggable pathways in cancer.

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We analyze ex-vivo-cultured primary cells using phosphoproteomics

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We investigate epithelial ovarian cancer (EOC) and healthy tissue

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We uncover expression of cancer-specific proteins and kinase signatures

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The kinase CDK7 phosphorylates POLR2A and regulates EOC cell proliferation

Clonal composition of human ovarian cancer based on copy number analysis reveals a reciprocal relation with oncogenic mutation status

Intratumoral heterogeneity of cancer cells remains largely unexplored. Here we investigated the composition of ovarian cancer and its biological relevance. A whole-genome single nucleotide polymorphism array was applied to detect the clonal composition of 24 formalin-fixed, paraffin-embedded samples of human ovarian cancer. Genome-wide segmentation data consisting of the log2 ratio (log2R) and B allele frequency (BAF) were used to calculate an estimate of the clonal composition number (CC number) for each tumor. Somatic mutation profiles of cancer-related genes were also determined for the same 24 samples by next-generation sequencing. The CC number was estimated successfully for 23 of the 24 cancer samples. The mean ± SD value for the CC number was 1.7 ± 1.1 (range of 0-4). A somatic mutation in at least one gene was identified in 22 of the 24 ovarian cancer samples, with the mutations including those in the oncogenes KRAS (29.2%), PIK3CA (12.5%), BRAF (8.3%), FGFR2 (4.2%), and JAK2 (4.2%) as well as those in the tumor suppressor genes TP53 (54.2%), FBXW7 (8.3%), PTEN (4.2%), and RB1 (4.2%). Tumors with one or more oncogenic mutations had a significantly lower CC number than did those without such a mutation (1.0 ± 0.8 versus 2.3 ± 0.9, P = 0.0027), suggesting that cancers with driver oncogene mutations are less heterogeneous than those with other mutations. Our results thus reveal a reciprocal relation between oncogenic mutation status and clonal composition in ovarian cancer using the established method for the estimation of the CC number.

Epithelial-to-Mesenchymal Transition in the Female Reproductive Tract: From Normal Functioning to Disease Pathology

Epithelial-to-mesenchymal transition (EMT) is a physiological process that is vital throughout the human lifespan. In addition to contributing to the development of various tissues within the growing embryo, EMT is also responsible for wound healing and tissue regeneration later in adulthood. In this review, we highlight the importance of EMT in the development and normal functioning of the female reproductive organs (the ovaries and the uterus) and describe how dysregulation of EMT can lead to pathological conditions, such as endometriosis, adenomyosis, and carcinogenesis. We also summarize the current literature relating to EMT in the context of ovarian and endometrial carcinomas, with a particular focus on how molecular mechanisms and the tumor microenvironment can govern cancer cell plasticity, therapy resistance, and metastasis.

The changing landscape of gynaecological cancer diagnosis: implications for histopathological practice in the 21st century

The era of molecular medicine has led to dramatically improved understanding of the genetic events that give rise to different types of cancers. In the case of gynaecological malignancies, this has resulted in distinct shifts in how these tumours are diagnosed in routine surgical pathology practice, with an increased emphasis on accurate subtype diagnosis. This has happened across all sites in the gynaecological tract and for most cell types, but in ways that are site-specific and may appear to be subtle, as in most instances the diagnostic terminology has not changed. For example, the diagnosis of clear cell carcinoma of the ovary is still in use, but the diagnostic criteria and clinical implications are different in 2017 from what they were in 2000. As a result, there can be a failure to appreciate how important these changes are and the resulting necessity of incorporating them into our daily practice. In this review we will describe changes in diagnostic surgical pathology occasioned by improved understanding of molecular events during pathogenesis, for cancers of ovary/tube, endometrium, cervix and vulva, and highlight how current practice differs from that of only a few years ago.

Risk-reducing salpingectomy: Let us be opportunistic

Because there is no screening test for ovarian cancer, effective prevention strategies may be the best way to reduce the mortality of this most lethal gynecologic malignancy. Increasing evidence supports the hypothesis that the fallopian tube is the site of origin for the vast majority of high-grade serous carcinomas. Our growing understanding of the pathogenesis of this disease offers a rare opportunity to explore new preventive measures, such as bilateral salpingectomy, which may provide great benefit without compromising ovarian function. If the tubal paradigm is accurate, then the impact of bilateral salpingectomy could extend to BRCA1 and BRCA2 mutation carriers, high-risk noncarriers, and average-risk women. The authors present a review of the literature on the role of risk-reducing salpingectomy in all women and in high-risk groups, with a focus on morbidity, ovarian function, potential clinical applicability, and epidemiological considerations. Cancer 2017;123:1714-1720. © 2017 American Cancer Society.

Frequency of papillary tubal hyperplasia (PTH), salpingoliths and transition from adenoma to borderline ovarian tumors (BOT): A systematic analysis of 74 BOT with different histologic types

Borderline ovarian tumors (BOT) arise from cystadenomas and represent a transition step within the development of low-grade ovarian carcinomas (Type I tumors). That pathway mirrors the adenoma-to-carcinoma sequence known for colorectal cancer. It has been suggested that papillary tubal hyperplasia (PTH) and salpingoliths may be associated with the development of BOT. To evaluate the frequency of the presence of benign cystadenoma and its transition to BOT in a given patient as well as the presence of PTH and salpingoliths we re-valuated in 74 consecutive cases of BOT with different histologic types. The majority of cases represented serous-BOT (60.8%), followed by mucinous BOT (25.7%), other histologic types were rare. 86.5% showed an adenoma-BOT sequence, which was seen in all mucinous BOT but was missed in 15.6% of serous BOT. Two cases had salpingoliths without associated PTH. PTH was seen in four out of the 74 (5.4%) BOT and occurred only in cases with serous histology. The vast majority of BOT represent a transition from benign cystadenoma to BOT in cases with mucinous and serous histology. Salpingoliths are rarely seen in association with BOT and occurred exclusively in BOT with serous histology. PTH may represent a distinct lesion but is rarely seen in association with BOT, especially in those with non-serous histology. Further studies are needed to evaluate the frequency and pathogenetic association of PTH with BOT.

Diagnosis of Ovarian Carcinoma Histotype Based on Limited Sampling: A Prospective Study Comparing Cytology, Frozen Section, and Core Biopsies to Full Pathologic Examination

Growing insights into the biological features and molecular underpinnings of ovarian cancer has prompted a shift toward histotype-specific treatments and clinical trials. As a result, the preoperative diagnosis of ovarian carcinomas based on small tissue sampling is rapidly gaining importance. The data on the accuracy of ovarian carcinoma histotype-specific diagnosis based on small tissue samples, however, remains very limited in the literature. Herein, we describe a prospective series of 30 ovarian tumors diagnosed using cytology, frozen section, core needle biopsy, and immunohistochemistry (p53, p16, WT1, HNF-1β, ARID1A, TFF3, vimentin, and PR). The accuracy of histotype diagnosis using each of these modalities was 52%, 81%, 85%, and 84% respectively, using the final pathology report as the reference standard. The accuracy of histotype diagnosis using the Calculator for Ovarian Subtype Prediction (COSP), which evaluates immunohistochemical stains independent of histopathologic features, was 85%. Diagnostic accuracy varied across histotype and was lowest for endometrioid carcinoma across all diagnostic modalities (54%). High-grade serous carcinomas were the most overdiagnosed on core needle biopsy (accounting for 45% of misdiagnoses) and clear cell carcinomas the most overdiagnosed on frozen section (accounting for 36% of misdiagnoses). On core needle biopsy, 2/30 (7%) cases had a higher grade lesion missed due to sampling limitations. In this study, we identify several challenges in the diagnosis of ovarian tumors based on limited tissue sampling. Recognition of these scenarios can help improve diagnostic accuracy as we move forward with histotype-specific therapeutic strategies.

Time to diagnosis of Type I or II invasive epithelial ovarian cancers: a multicentre observational study using patient questionnaire and primary care records

OBJECTIVE

To compare time to diagnosis of the typically slow-growing Type I (low-grade serous, low-grade endometrioid, mucinous, clear cell) and the more aggressive Type II (high-grade serous, high-grade endometrioid, undifferentiated, carcinosarcoma) invasive epithelial ovarian cancer (iEOC).

DESIGN

Multicentre observational study.

SETTING

Ten UK gynaecological oncology centres.

POPULATION

Women diagnosed with primary EOC between 2006 and 2008.

METHODS

Symptom data were collected before diagnosis using patient questionnaire and primary-care records. We estimated patient interval (first symptom to presentation) using questionnaire data and diagnostic interval (presentation to diagnosis) using primary-care records. We considered the impact of first symptom, referral and stage on intervals for Type I and Type II iEOC.

MAIN OUTCOME MEASURES

Patient and diagnostic intervals.

RESULTS

In all, 78% of 60 Type I and 21% of 134 Type II iEOC were early-stage. Intervals were comparable and independent of stage [e.g. median patient interval for Type I: early-stage 0.3 months (interquartile range 0.3-3.0) versus late-stage 0.3 months (interquartile range 0.3-4.5), P = 0.8]. Twenty-seven percent of women with Type I and Type II had diagnostic intervals of at least 9 months. First symptom (questionnaire) was also similar, except for the infrequent abnormal bleeding (Type I 15% versus Type II 4%, P = 0.01). More women with Type I disease (57% versus 41%, P = 0.04) had been referred for suspected gynaecological cancer. Median time from referral to diagnosis was 1.4 months for women with iEOC referred via a 2-week cancer referral to any specialty compared with 2.6 months (interquartile range 2.0-3.7) for women who were referred routinely to gynaecology.

CONCLUSION

Overall, shorter diagnostic delays were seen when a cancer was suspected, even if the primary tumour site was not recognised to be ovarian. Despite differences in carcinogenesis and stage for Type I and Type II iEOC, time to diagnosis and symptoms were similar. Referral patterns were different, implying subtle symptom differences. If symptom-based interventions are to impact on ovarian cancer survival, it is likely to be through reduced volume rather than stage-shift. Further research on histological subtypes is needed.

TWEETABLE ABSTRACT

No difference in time to diagnosis for Type I versus Type II invasive epithelial ovarian cancers.

[Dualistic classification of epithelial ovarian cancer: Is it clinically relevant?]

Malignant epithelial tumors (carcinomas) are the most common ovarian cancers and the most lethal gynecological malignancies. Based on their heterogeneous morphology, a dualistic model of carcinogenesis was proposed in 2004. Type I carcinomas, composed of low grade serous, endometrioid, mucinous, clear cell carcinomas and malignant Brenner tumors, were distinct from type II carcinomas (high grade serous, undifferentiated carcinomas and carcinosarcomas). However, clinical studies failed to demonstrate the prognostic value of such a classification. The main reproach to this dualistic model was that it lumped together in type I tumors, heterogeneous lesions such as clear cell and mucinous carcinomas. Recent advances on molecular genetic alterations and precursor lesions favor the classification of ovarian carcinomas as five distinct diseases. The dualistic model of carcinogenesis in type I and II can finally be applied only to serous ovarian carcinomas (low grade and high grade).

Morphologic and Molecular Characteristics of Mixed Epithelial Ovarian Cancers

Epithelial ovarian cancer (EOC) consists of 5 major histotypes: high-grade serous carcinoma (HGSC), endometrioid carcinoma (EC), clear cell carcinoma (CCC), mucinous carcinoma (MC), and low-grade serous carcinoma (LGSC). Each can have a broad spectrum of morphologic appearances, and 1 histotype can closely mimic histopathologic features more typical of another. Historically, there has been a relatively high frequency of mixed, defined by 2 or more distinct histotypes present on the basis of routine histopathologic assessment, histotype carcinoma diagnoses (3% to 11%); however, recent immunohistochemical (IHC) studies identifying histotype-specific markers and allowing more refined histotype diagnoses suggest a much lower incidence. We reviewed hematoxylin and eosin-stained slides from 871 cases of EOC and found the frequency of mixed carcinomas to be 1.7% when modern diagnostic criteria are applied. Through international collaboration, we established a cohort totaling 22 mixed EOCs, consisting of 9 EC/CCC, 4 EC/LGSC, 3 HGSC/CCC, 2 CCC/MC, and 4 other combinations. We interrogated the molecular differences between the different components of each case using IHC, gene expression, and hotspot sequencing analyses. IHC data alone suggested that 9 of the 22 cases were not mixed tumors, as they presented a uniform immuno-phenotype throughout, and these cases most probably represent morphologic mimicry and variation within tumors of a single histotype. Synthesis of molecular data further reduces the incidence of mixed carcinomas. On the basis of these results, true mixed carcinomas with both morphologic and molecular support for the presence of >1 histotype within a given tumor represent <1% of EOCs.

Novel high-grade serous epithelial ovarian cancer cell lines that reflect the molecular diversity of both the sporadic and hereditary disease

Few cell line models of epithelial ovarian cancer (EOC) have been developed for the high-grade serous (HGS) subtype, which is the most common and lethal form of gynaecological cancer. Here we describe the establishment of six new EOC cell lines spontaneously derived from HGS tumors (TOV2978G, TOV3041G and TOV3291G) or ascites (OV866(2), OV4453 and OV4485). Exome sequencing revealed somatic TP53 mutations in five of the cell lines. One cell line has a novel BRCA1 splice-site mutation, and another, a recurrent BRCA2 nonsense mutation, both of germline origin. The novel BRCA1 mutation induced abnormal splicing, mRNA instability, resulting in the absence of BRCA1 protein. None of the cell lines harbor mutations in KRAS or BRAF, which are characteristic of other EOC subtypes. SNP arrays showed that all of the cell lines exhibited structural chromosomal abnormalities, copy number alterations and regions of loss of heterozygosity, consistent with those described for HGS. Four cell lines were able to produce 3D-spheroids, two exhibited anchorage-independent growth, and three (including the BRCA1 and BRCA2 mutated cell lines) formed tumors in SCID mice. These novel HGS EOC cell lines and their detailed characterization provide new research tools for investigating the most common and lethal form of EOC.

Intra-tumor heterogeneity in TP53 null High Grade Serous Ovarian Carcinoma progression

Background

High grade serous ovarian cancer is characterised by high initial response to chemotherapy but poor outcome in the long term due to acquired resistance. One of the main genetic features of this disease is TP53 mutation. The majority of TP53 mutated tumors harbor missense mutations in this gene, correlated with p53 accumulation. TP53 null tumors constitute a specific subgroup characterised by nonsense, frameshift or splice-site mutations associated to complete absence of p53 expression. Different studies show that this kind of tumors may have a worse prognosis than other TP53 mutated HGSC.

Methods

In this study, we sought to characterise the intra-tumor heterogeneity of a TP53 null HGSC consisting of six primary tumor samples, two intra-pelvic and four extra-pelvic recurrences using exome sequencing and comparative genome hybridisation.

Results

Significant heterogeneity was found among the different tumor samples, both at the mutational and copy number levels. Exome sequencing identified 102 variants, of which only 42 were common to all three samples; whereas 7 of the 18 copy number changes found by CGH analysis were presented in all samples. Sanger validation of 20 variants found by exome sequencing in additional regions of the primary tumor and the recurrence allowed us to establish a sequence of the tumor clonal evolution, identifying those populations that most likely gave rise to recurrences and genes potentially involved in this process, like GPNMB and TFDP1. Using functional annotation and network analysis, we identified those biological functions most significantly altered in this tumor. Remarkably, unexpected functions such as microtubule-based movement and lipid metabolism emerged as important for tumor development and progression, suggesting its potential interest as therapeutic targets.

Conclusions

Altogether, our results shed light on the clonal evolution of the distinct tumor regions identifying the most aggressive subpopulations and at least some of the genes that may be implicated in its progression and recurrence, and highlights the importance of considering intra-tumor heterogeneity when carrying out genetic and genomic studies, especially when these are aimed to diagnostic procedures or to uncover possible therapeutic strategies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1952-z) contains supplementary material, which is available to authorized users.