Are all pelvic (nonuterine) serous carcinomas of tubal origin? Am J Surg Pathol. 2010;34:1407-1416. [PMID: 20861711 DOI: 10.1097/pas.0b013e3181ef7b16]

Pathology of the Fallopian Tube: Tubal Involvement by Ovarian Tumors and Incidental Findings in the Nontumoral Setting

The fallopian tube is thought to be the site of origin of most high-grade serous carcinomas (HGSCs). However, how often the tube is abnormal in the setting of other ovarian tumors is unknown. The aim of this study is to define the frequency of tubal abnormalities in the tumoral (n = 245) and nontumoral (n = 184) setting. We found that in ovarian tumors, 52.2% of the tubes were normal, while 39.2% were affected by the tumor. Abnormal tubes were found in 80% of HGSCs, in 21% of mucinous carcinomas, in 83.3% of seromucinous carcinomas, in 33.3% of endometrioid carcinomas, in 20% of clear-cell carcinomas, and in 10.5% of borderline tumors. Among normal tubes, almost 70% were histologically normal; transitional metaplasia was present in 17.4%, endometriosis in 8.1%, and adenofibroma in 2.2%, and 1.1% had an incidental serous intraepithelial tubal carcinoma. To conclude, the fallopian tube is abnormal in most serous carcinomas, and in a smaller number of endometrioid, clear-cell and mucinous carcinomas as well as borderline tumors. It is often abnormal in seromucinous tumors, but larger series are needed to study this rare subtype.

Clinical Impact of Somatic Variants in Homologous Recombination Repair-Related Genes in Ovarian High-Grade Serous Carcinoma

Purpose

In this study, we investigated the frequencies of mutations in DNA damage repair genes including BRCA1, BRCA2, homologous recombination genes and TP53 gene in ovarian high-grade serous carcinoma, alongside those of germline and somatic BRCA mutations, with the aim of improving the identification of patients suitable for treatment with poly(ADP-ribose) polymerase inhibitors.

Materials and Methods

Tissue samples from 77 Korean patients with ovarian high-grade serous carcinoma were subjected to next-generation sequencing. Pathogenic alterations of 38 DNA damage repair genes and TP53 gene and their relationships with patient survival were examined. Additionally, we analyzed BRCA germline variants in blood samples from 47 of the patients for comparison.

Results

BRCA1, BRCA2, and TP53 mutations were detected in 28.6%, 5.2%, and 80.5% of the 77 patients, respectively. Alterations in RAD50, ATR, MSH6, MSH2, and FANCA were also identified. At least one mutation in a DNA damage repair gene was detected in 40.3% of patients (31/77). Germline and somatic BRCA mutations were found in 20 of 47 patients (42.6%), and four patients had only somatic mutations without germline mutations (8.5%, 4/47). Patients with DNA damage repair gene alterations with or without TP53 mutation, exhibited better disease-free survival than those with TP53 mutation alone.

Conclusion

DNA damage repair genes were mutated in 40.3% of patients with high-grade serous carcinoma, with somatic BRCA mutations in the absence of germline mutation in 8.5%. Somatic variant examination, along with germline testing of DNA damage repair genes, has potential to detect additional candidates for PARP inhibitor treatment.

Fallopian Tube Neoplasia and Mimics

This review discusses select fallopian tube entities and their associated mimics. It first focuses on adenomatoid tumors, the most common benign tumor of the fallopian tube. High-grade serous carcinoma and its precursor, serous tubal intraepithelial carcinoma, are then addressed. Finally, attention is turned to endometrioid proliferations of the fallopian tube. A diagnostic approach is provided for these lesions, with an emphasis on differential diagnoses and situations in which a benign lesion may appear malignant, and vice-versa.

Ovarian High-Grade Serous Carcinoma: Assessing Pathology for Site of Origin, Staging and Post-neoadjuvant Chemotherapy Changes

High-grade serous (HGSC) stands apart from the other ovarian cancer histotypes in being the most frequent, in occurring as part of a genetic predisposition in a significant proportion of cases, and in having the poorest clinical outcomes. Although the pathologic diagnosis of HGSC is now made with high accuracy, there remain areas of disagreement regarding viewpoints on tissue site of origin and designation of primary site, with impact on staging in low-stage cases, as well as difficulties in reproducible and clinically relevant reporting of HGSC in specimens taken after neoadjuvant chemotherapy. These areas are discussed in the current article.

The fallopian tube as origin of ovarian cancer: Change of diagnostic and preventive strategies

Ovarian cancer is the leading cause of gynecologic cancer death in the world, and its prevention and early diagnosis remain the key to its treatment, especially for high‐grade serous carcinoma (HGSC). Accumulating epidemiological and molecular evidence has shown that HGSC originates from fallopian tube secretory cells through serous tubal intraepithelial carcinoma. Comprehensive molecular analyses and mouse studies have uncovered the key driver events for serous carcinogenesis, providing novel molecular targets. Risk‐reducing bilateral salpingo‐oophorectomy (RRSO) has been proposed to reduce the subsequent occurrence of serous carcinoma in high‐risk patients with BRCA mutations. However, there is no management strategy for isolated precursors detected at RRSO, and the role of subsequent surgery or chemotherapy in preventing serous carcinoma remains unclear. Surgical menopause due to RRSO provides a variety of problems related to patients’ quality of life, and the risks and benefits of hormone replacement are under investigation, especially for women without a previous history of breast cancer. An additional surgical option, salpingectomy with delayed oophorectomy, has been proposed to prevent surgical menopause. The number of opportunistic salpingectomies at the time of surgery for benign disease to prevent the future occurrence of HGSC has increased worldwide. Thus, the changing concept of the origin of serous carcinoma has provided us a great opportunity to develop novel diagnostic and therapeutic approaches.

Evaluation of SEE-FIM (Sectioning and Extensively Examining the FIMbriated End) Protocol in Identifying Fallopian Tube Precursor Lesions in Women with Ovarian Tumors

BACKGROUND

Studies of prophylactic salpingo-oophorectomies in high-risk population led to incidental finding of precursor lesions in the fimbrial end of fallopian tube rather than the ovary. Early detection of these precursor lesions can be helpful in the prevention of ovarian tumors, and the presence of these lesions can be more efficiently studied by applying Sectioning and Extensively Examining the FIMbriated End (SEE-FIM) protocol.

AIM

To study precursor lesions of fallopian tubes associated with ovarian tumors by applying SEE-FIM protocol.

MATERIALS AND METHODS

Sixty specimens of hysterectomy with bilateral salpingo-oophorectomy, clinically diagnosed as ovarian tumor (study group), were examined by SEE-FIM protocol. Specimens without ovarian tumor were taken as the control group, and same protocol was applied on them. Histological changes in fallopian tube were grouped either as tubal intraepithelial carcinoma (TIC), tubal intraepithelial lesion (TIL), only stratification and negative for any changes.

RESULTS

Out of 60 cases in the study group, 10.00% (6/60) cases showed TIC, 38.34% (23/60) cases revealed TIL, 23.33% (14/60) cases showed changes of stratification and the rest were negative for any changes. Among these 60 cases, there were 7 cases of high-grade serous carcinoma, 5 (71.43%) of them showed changes of TIC. In the control group, out of 60 cases, none showed TIC changes, TIL was noted in 6.66% (4/60) cases, changes of stratification were seen in 26.67% (16/60) cases and the rest were negative for any changes.

CONCLUSION

SEE-FIM protocol maximizes the examination of fimbrial end and is helpful in identifying precursor lesions of ovarian epithelial tumors.

A Comprehensive Review of Ovarian Serous Carcinoma

Although ovarian serous carcinoma is a well-studied human gynecologic malignancy, this high-grade tumor remains fatal. The main purpose of this review is to summarize the accumulated evidence on serous malignant tumors and to clarify the unresolved issues. We discuss the 8 dichotomies of serous carcinoma: high grade versus low grade, ovarian versus extraovarian primary, extrauterine versus uterine primary, sporadic versus hereditary, orthodox versus alternative histology, p53 overexpression versus complete absence of immunophenotype, TP53-mutated versus intact precursor, and therapy responsive versus refractory. In addition, we summarize the molecular classification of high-grade serous carcinoma. This review would lead readers to rapid and parallel developments in understanding high-grade serous carcinoma.

Estrogen and EGFR Pathways Regulate Notch Signaling in Opposing Directions for Multi-Ciliogenesis in the Fallopian Tube

The lumen of the fallopian tube (FT) is lined with columnar epithelium composed of secretory and ciliated cells, both of which are important for reproduction. However, the molecular mechanism regulating cell fate remains controversial. In this study, we established a primary culture system using porcine fallopian tube epithelial cells (FTECs) to study the differentiation mechanism. We found that estrogen promoted the differentiation of multi-ciliated cells (MCCs) through estrogen receptor β, following the reduction of DLL1, a ligand of Notch. Meanwhile, epidermal growth factor (EGF), a regulator of epithelial homeostasis and differentiation, suppressed ciliogenesis by the activation of Notch signaling. However, the estrogen pathway did not affect the activation of the EGF pathway. Taken together, the differentiation of MMCs in FT depends on the balance of EGF and estrogen signaling, either of which inhibits or stimulates the Notch signaling pathway respectively.

Lineage tracing suggests that ovarian endosalpingiosis does not result from escape of oviductal epithelium

Most high-grade serous carcinomas are thought to arise from Fallopian tube epithelium (FTE), but some likely arise outside of the tube, perhaps from ectopic tubal-type epithelium known as endosalpingiosis. Importantly, the origin of endosalpingiosis is poorly understood. The proximity of the tubal fimbriae to the ovaries has led to the proposal that disruptions in the ovarian surface that occur during ovulation may allow detached FTE to implant in the ovary and form tubal-type glands and cysts. An alternative model suggests that cells present in ectopic locations outside the Müllerian tract retain the capacity for multi-lineage differentiation and can form glands with tubal-type epithelium. We used double transgenic Ovgp1-iCreER^T2 ;R26R^LSL-eYFP mice, which express an eYFP reporter protein in OVGP1-positive tissues following transient tamoxifen (TAM) treatment, to track the fate of oviductal epithelial cells. Cohorts of adult mice were given TAM to activate eYFP expression in oviductal epithelium, and ovaries were examined at time points ranging from 2 days to 12 months post-TAM. To test whether superovulation might increase acquisition of endosalpingiosis, additional cohorts of TAM-treated mice underwent up to five cycles of superovulation and ovaries were examined at 1, 6, and 12 months post-TAM. Ovaries were sectioned in their entirety to identify endosalpingiosis. Immunohistochemical staining for PAX8, tubulin, OVGP1, and eYFP was employed to study endosalpingiosis lesions. Ovarian endosalpingiosis was identified in 14.2% of TAM-treated adult mice. The endosalpingiotic inclusion glands and cysts were lined by secretory and ciliated cells and expressed PAX8, tubulin, OVGP1, and eYFP. Neither age nor superovulation was associated with a significant increase in endosalpingiosis. Endosalpingiosis was also occasionally present in the ovaries of pre-pubertal mice. The findings imply that ovarian endosalpingiosis in the mouse does not likely arise as a consequence of detachment and implantation of tubal epithelium and other mechanisms may be relevant. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Challenges in Managing Patients with Hereditary Cancer at Gynecological Services

Aim

To reveal current problems and challenges faced by our gynecologic services department in managing patients with hereditary cancers.

Methods

We collected clinical data of patients with hereditary cancers, identified via genetic testing (or clinically diagnosed in cases of Cowden syndrome or Peutz–Jeghers syndrome), and treated in our gynecological department from 2012 to 2018.

Results

Fifteen patients had hereditary breast and ovarian cancer (HBOC), 6 had Lynch syndrome, 2 had Cowden syndrome, and 2 had Peutz–Jeghers syndrome. Five patients diagnosed with HBOC were younger than 40 years at diagnosis. Risk-reducing salpingo-oophorectomy (RRSO) was performed on 1 patient with a BRCA1 mutation at age 38 years. Seven patients overall underwent RRSO, and none had malignancies on pathological examinations. Peritoneal washing cytology (PWC) was suspicious for malignancy in one patient; however, subsequent PWC at 6 months after RRSO was negative. A patient with endometrial cancer and Lynch syndrome and a patient with atypical endometrial hyperplasia (AEH) and Cowden syndrome strongly desired fertility preservation. They achieved remission after medroxyprogesterone acetate treatment and multiple dilations and curettages, respectively. One patient with Lynch syndrome developed AEH after 11 years of surveillance. Laparotomy revealed adjacent low-grade and high-grade serous ovarian cancer with positive ascites cytology. She had no recurrence during 7-year follow-up after laparotomy.

Conclusion

Managing patients with hereditary cancer, positive or false-positive ascites cytology discovered during RRSO, and desired preservation of fertility is highly challenging.

Association between Cigarette Smoking and Histotype-Specific Epithelial Ovarian Cancer: A Review of Epidemiologic Studies

Many studies have demonstrated that smoking can influence ovarian cancer risk and survival; however, the number of studies investigating this relationship according to histologic subtypes is limited. We conducted a review of epidemiologic research that assessed the role of smoking on ovarian cancer risk and survival after diagnosis, specifically capturing studies that discerned between various histologic subtypes of this disease. In the majority of studies, current smoking was associated with increased risk of mucinous cancer. There was also evidence of a decreased risk of clear cell and endometrioid histotypes. No significant association was observed between cigarette smoking and serous cancer. In the studies investigating the relationship between smoking and survival, all the studies reported an increased risk of mortality associated with smoking. Smoking appeared to be a risk factor for both ovarian cancer risk and mortality. Future studies need to investigate further a potential link between smoking and ovarian cancer by having a better assessment of exposure to smoking and having a larger number of participants with the ability to detect associations within rare histotypes.

Molecular Classification of Epithelial Ovarian Cancer Based on Methylation Profiling: Evidence for Survival Heterogeneity

PURPOSE

Ovarian cancer is a heterogeneous disease that can be divided into multiple subtypes with variable etiology, pathogenesis, and prognosis. We analyzed DNA methylation profiling data to identify biologic subgroups of ovarian cancer and study their relationship with histologic subtypes, copy number variation, RNA expression data, and outcomes.

EXPERIMENTAL DESIGN

A total of 162 paraffin-embedded ovarian epithelial tumor tissues, including the five major epithelial ovarian tumor subtypes (high- and low-grade serous, endometrioid, mucinous, and clear cell) and tumors of low malignant potential were selected from two different sources: The Polish Ovarian Cancer study, and the Surveillance, Epidemiology, and End Results Residual Tissue Repository (SEER RTR). Analyses were restricted to Caucasian women. Methylation profiling was conducted using the Illumina 450K methylation array. For 45 tumors array copy number data were available. NanoString gene expression data for 39 genes were available for 61 high-grade serous carcinomas (HGSC).

RESULTS

Consensus nonnegative matrix factorization clustering of the 1,000 most variable CpG sites showed four major clusters among all epithelial ovarian cancers. We observed statistically significant differences in survival (log-rank test, P = 9.1 × 10^-7) and genomic instability across these clusters. Within HGSC, clustering showed three subgroups with survival differences (log-rank test, P = 0.002). Comparing models with and without methylation subgroups in addition to previously identified gene expression subtypes suggested that the methylation subgroups added significant survival information (P = 0.007).

CONCLUSIONS

DNA methylation profiling of ovarian cancer identified novel molecular subgroups that had significant survival difference and provided insights into the molecular underpinnings of ovarian cancer.See related commentary by Ishak et al., p. 5729.

Serous Adenocarcinoma of Fallopian Tubes: Histological and Immunohistochemical Aspects

BACKGROUND

Although primary cancer of the fallopian tubes is a relatively rare type of tumor in female reproductive organs, its mortality is quite high. It is important to identify molecular and biological markers of this malignancy that determine its specific phenotype.

METHODS

The study was carried out on samples received from 71 female patients with primary cancer of the fallopian tubes. The main molecular and biological properties, including hormone status (estrogen receptor [ER], progesterone receptor [PR]), human epidermal growth factor receptor (HER2)/neu expression, proliferative potential (Ki-67), apoptosis (p53, Bcl-2), and pro-angiogenic (vascular endothelial growth factor) quality of serous tumors were studied in comparison with clinical and morphological characteristics.

RESULTS

ER and PR expression is accompanied by low grade neoplasia, early clinical disease stage, and absence of lymphogenic metastasis (p < .001). HER2/neu expression is not typical for primary cancer of the fallopian tubes. Ki-67 expression is characterized by an inverse correlation with ER and PR (p < .05) and is associated with lymphogenic metastasis (p < .01). p53+ status correlates with high grade malignancy, tumor progression, metastasis, negative ER/PR (p < .001), and negative Bcl-2 status (p < .05). Positive Bcl-2 status is positively correlated with ER and PR expression and low grade malignancy.

CONCLUSIONS

Complex morphologic (histological and immunohistochemical) study of postoperative material allows estimation of the degree of malignancy and tumor spread to enable appropriate treatment for each case.

Ovarian Carcinosarcoma and Concurrent Serous Tubal Intraepithelial Carcinoma With Next-Generation Sequencing Suggesting an Origin From the Fallopian Tube

Background. Ovarian carcinosarcomas are rare aggressive biphasic tumors. Evidence suggests that these tumors are monoclonal and that the sarcoma component is derived from a stem cell undergoing divergent differentiation. Currently, there remains a paucity of data regarding its origin, with few reports suggesting an association with serous tubal intraepithelial carcinoma (STIC) by immunohistochemistry and genetics. Objective. We sought to determine the relationship of carcinosarcoma to high-grade serous carcinoma and STIC by investigating for similar mutation signatures through next-generation sequencing. Methodology. A case of carcinosarcoma with associated high-grade serous carcinoma and STIC was macrodissected, and next-generation sequencing was performed on each component separately. Results. The STIC, high-grade serous carcinoma component, and chondrosarcoma component were all diffusely positive for p53 and p16 by immunohistochemistry. Next-generation sequencing demonstrated an identical TP53 gene c.376-1G>A 5' splice site pathogenic mutation in all 3 components. Conclusions. Our findings suggest that carcinosarcomas may also originate from the fallopian tube.

Kang SK, Reinhold C, Atri M, Benson CB, Bhosale PR, Jhingran A, Lakhman Y, Maturen KE, Nicola R, Pandharipande PV, Salazar GM, Shipp TD, Simpson L, Small W, Sussman BL, Uyeda JW, Wall DJ, Whitcomb BP, Zelop CM, Glanc P. ACR Appropriateness Criteria® Staging and Follow-Up of Ovarian Cancer

In the management of epithelial ovarian cancers, imaging is used for cancer detection and staging, both before and after initial treatment. The decision of whether to pursue initial cytoreductive surgery for ovarian cancer depends in part on accurate staging. Contrast-enhanced CT of the abdomen and pelvis (and chest where indicated) is the current imaging modality of choice for the initial staging evaluation of ovarian cancer. Fluorine-18-2-fluoro-2-deoxy-d-glucose PET/CT and MRI may be appropriate for problem-solving purposes, particularly when lesions are present on CT but considered indeterminate. In patients who achieve remission, clinical suspicion for relapse after treatment prompts imaging evaluation for recurrence. Contrast-enhanced CT is the modality of choice to assess the extent of recurrent disease, and fluorine-18-2-fluoro-2-deoxy-d-glucose PET/CT is also usually appropriate, as small metastatic foci may be identified. If imaging or clinical examination confirms a recurrence, the extent of disease and timing of disease recurrence then determines the choice of treatments, including surgery, chemotherapy, and radiation therapy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Fallopian Tube Epithelial Changes in Ovarian Serous Tumors Compared with Control Group: A Single-Center Study

BACKGROUND

Recent studies have hypothesized that distal end of fallopian tube is a possible origin of ovarian serous carcinoma. This study investigated histopathological changes in fallopian tube epithelium (FTE) of the patients with ovarian serous tumors compared with control group.

MATERIALS AND METHODS

In a prospective cross-sectional study, fallopian tubes (right and left) of 34 cases with ovarian serous tumors were collected from patients who underwent surgery in two major gynecological centers affiliated to Shiraz University of Medical Sciences, Shiraz, Iran (2012-2015). They are composed of 21 (61.8%) high-grade serous carcinomas (HGSCs), 5 (14.7%) borderline ones, and 8 (23.5%) benign serous tumors. As control group, fallopian tubes of 72 hystrectomy cases without ovarian tumor were added to the study. Both tubes of all of the cases were submitted entirely, according to the protocol of sectioning and extensively examining the fimbriated end. The results were statistically analyzed using SPSS-PC windows and Chi-square tests.

RESULTS

Significant differences were found between the cases and control group in tubal epithelial cell stratification (especially >3 cell layers thickness), atypia, mitosis, glandular complexity, tufting, and detached epithelial cells (P < 0.05). These findings particularly atypia and mitosis were more frequently seen in the ampulla and fimbriated end of high-grade ovarian serous carcinomas.

CONCLUSION

Our results showed that premalignant epithelial changes of the ampulla and the distal end of FTE were seen in some of the patients with ovarian HGSCs. Therefore, FTE could be one of the sources of ovarian serous carcinoma.

Gynecologic Cancers: Molecular Updates 2018

Ovarian carcinoma continues to be a concern for woman and maintains significant morbidity and mortality. Emerging molecular markers are providing additional opportunities for effective diagnosis and prognosis of disease. An integrated clinicopathologic and molecular classification of gynecologic malignancies has the potential to refine the clinical risk prediction of patients with cancer and to provide more tailored treatment recommendations.

Methylation and ovarian cancer: Can DNA methylation be of diagnostic use?

Ovarian cancer is a silent killer and, due to late diagnosis and frequent chemo resistance in patients, the primary cause of fatality amongst the various types of gynecological cancer. The discovery of a specific and sensitive biomarker for ovarian cancer could improve early diagnosis, thereby saving lives. Biomarkers could also improve treatment, by predicting which patients will benefit from specific treatment strategies. DNA methylation is an epigenetic mechanism, and 'methylation imbalance' is characteristic of cancer. Previous research suggests that changes in DNA methylation can be used diagnostically, and that they may predict resistance to treatment. This paper gives an up-to-date overview of research investigating the potential of DNA methylation-based markers for diagnostics, prognostics, screening and prediction of drug resistance for ovarian cancer patients. DNA methylation cancer-biomarkers may be useful for cancer treatment, particularly since they are chemically stable and since cancer-associated changes in methylation typically precedes tumor growth. DNA methylation markers could improve diagnosis and treatment and might even be used for screening in the future. Furthermore, DNA methylation biomarkers could facilitate the development of precision medicine. However, at this point no biomarkers for ovarian cancer have a sufficient combination of sensitivity and specificity in a clinical setting. A reason for this is that most studies have focused on a single or a few methylation sites. More large screenings and genome-wide studies must be performed to increase the chance of identifying a DNA methylation marker which can identify ovarian cancer.

When Is "Type I" Ovarian Cancer Not "Type I"? Indications of an Out-Dated Dichotomy

The dualistic classification of epithelial ovarian cancer (EOC) into “type I” and “type II” is widely applied in the research setting; it is used as a convenient way of conceptualizing different mechanisms of tumorigenesis. However, this classification conflicts with recent molecular insights of the etiology of EOC. Molecular and cell of origin studies indicate that while type II tumors could be classed together, type I tumors are not homogenous, even within the histological types, and can have poor clinical outcomes. Type II high grade serous carcinoma and type I low grade serous carcinomas best fit the description of the dualistic model, with different precursors, and distinct molecular profiles. However, endometriosis-associated cancers should be considered a separate group, without assuming an indolent course or type I genetic profiles. Furthermore, the very clear differences between mucinous ovarian carcinomas and other type I tumors, including an uncertain origin, and heterogeneous mutational spectrum and clinical behavior, indicate a non-type I classification for this entity. The impression that only type II carcinomas are aggressive, have poor prognosis, and carry TP53 mutations is an unhelpful misinterpretation of the dualistic classification. In this review, we revisit the history of EOC classification, and discuss the misunderstanding of the dualistic model by comparing the clinical and molecular heterogeneity of EOC types. We also emphasize that all EOC research, both basic and clinical, should consider the subtypes as different diseases beyond the type I/type II model, and base novel therapies on the molecular characteristics of each tumor.

Population Frequency of Serous Tubal Intraepithelial Carcinoma (STIC) in Clinical Practice Using SEE-Fim Protocol

Frequent detection of serous tubal intraepithelial carcinoma (STIC) among BRCA1/2 mutation carriers undergoing risk-reducing surgery prompted the hypothesis that many adnexal high-grade serous carcinomas (HGSCs) arise from the fallopian tube, rather than the ovary, as supposed. The changing paradigm has important implications for HGSC prevention. Most data related to the frequency of STIC are derived from case series and estimates vary widely. Therefore, we analyzed population-based data from 10 523 surgeries including salpingectomy (Jan 2014-Dec 2016) that were examined using the "Sectioning and Extensively Examining the Fimbria" protocol, which optimizes STIC detection. Overall, STIC was detected in 40 (0.38%) specimens, including 32 diagnosed with concurrent gynecologic cancer. STIC was detected in 8 (<0.01%) of 9392 cases with benign diagnoses. We conclude that the relative rarity of STIC diagnoses in routine pathology practice has critical implications for research aiming to elucidate the pathogenesis of HGSC and developing prevention strategies.

Sectioning and extensively examining the fimbriated end (SEE-FIM) of the fallopian tube in routine practices, is it worth the effort?

AIM

To determine the prevalence of fallopian tube high-grade serous carcinoma (HGSC) and to analyze the benefit of the sectioning and extensively examining the fimbriated end (SEE-FIM) protocol.

METHODS

Fallopian tubes from 450 patients with risk-reducing salpingo-oophorectomy, or tumor of the ovary, endometrium, fallopian tube or peritoneum were examined using the SEE-FIM protocol. Microscopic tubal pathology and the number of paraffin blocks used were evaluated. Immunostaining for p53 was performed to confirm TP53 mutation. Cost effectiveness was determined by equation of incremental cost-effectiveness ratio.

RESULTS

Tubal HGSC were detected in 25 out of 70 cases of pelvic extrauterine HGSC, in 1 case of endometrioid carcinoma, and 4 cases of uterine serous carcinoma out of 250 cases of endometrial neoplasm. The mean number of tissue blocks per case was 6. The incremental cost for detecting one case of coexisting fallopian tube HGSC in the study population was 94 Thai baht/3 USD per case.

CONCLUSION

The SEE-FIM protocol facilitates identification of lesions that are not distinguishable by classical sampling protocol, and this results in more accurate tumor staging and a better understanding of the carcinogenesis. The benefit of the SEE-FIM protocol was demonstrated, especially in cases at high risk for coexisting fallopian tube carcinoma.

Resection for Primary Retroperitoneal Serous Adenocarcinoma and Liver Metastasis

Primary retroperitoneal serous adenocarcinoma (PRSA) is a rare malignancy of which only seven cases have been reported in the literature. The clinical features and outcomes of PRSA are not well understood. We herein report a case of PRSA with liver metastasis in a 74-year-old woman who was treated with surgical excision. The tumor cells were positive for estrogen receptor, Wilms tumor 1, PAX8, p53, and cytokeratin AE1/AE3. The final diagnosis was PRSA and liver metastasis. The pathological features of PRSA resemble those of ovarian serous carcinoma, which suggests that a combination of surgical excision with adjuvant chemotherapy may be the best option.

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.

Protein tyrosine phosphatase L1 inhibits high-grade serous ovarian carcinoma progression by targeting IκBα

Background

High-grade serous ovarian cancer (HGSOC) represents most of the ovarian cancers and accounts for 70%-80 % of related deaths. The overall survival of HGSOC has not been remarkably improved in the past decades, due to the tumor dissemination in peritoneal cavity and invasion of adjacent organs. Therefore, identifying molecular biomarkers is invaluable in helping predicting clinical outcomes and developing targeted chemotherapies. Although there have been studies revealing the prognostic significance of protein tyrosine phosphatase L1 (PTPL1) in breast cancer and lung cancer, its involvement and functions in HGSOC remains to be elucidated.

Methods

We retrospectively enrolled a cohort of HGSOC patients after surgical resection. And analyzed the mRNA and protein levels of PTPL1 in tissue samples.

Results

We found that PTPL1 presented a lower expression in HGSOC tissues than in adjacent normal ovarian tissues. Besides, the PTPL1 level was negatively correlated with tumor stage, implying its potential role as a tumor suppressor. Univariate and multivariate analyses identified that patients with higher PTPL1 showed a better overall survival compared to those with lower PTPL1 expression. In addition, cellular experiments confirmed the role of PTPL1 in suppressing tumor proliferation and invasion. Furthermore, we demonstrated that PTPL1 negatively regulated phosphorylation of tyrosine 42 on IκBα (IκBα-pY42). To our knowledge, this is the initial finding on PTPL1 targeting IκBα-pY42 site. Finally, our data indicated that PTPL1 suppressed tumor progression by dephosphorylating IκBα-pY42, which stabilized IκBα and attenuated nucleus translocation of NF-κB.

Conclusion

Our study revealed a tumor-suppressing role of PTPL1 in HGSOC by targeting IκBα.

Clinicopathologic features and BRCA mutations in primary fallopian tube cancer in Japanese women

Objective

The present study aimed to clarify the clinicopathological features, including the level of p53 protein expression and BRCA mutations, of primary fallopian tube cancer (PFTC) in Japanese women.

Methods

A multicenter clinical survey was conducted at three Japanese institutions. Clinical data in patients with PFTC between 1998 and 2016 were collected. Immunohistochemical staining of p53 and BRCA mutation analysis by exome sequence using paraffin-embedded surgical resected specimens were performed.

Results

A total of 40 patients with PFTC were enrolled in the study. The median age was 58 years (range: 38-78 years); 31 patients were menopausal. Thirty-four (85.0%) patients were diagnosed with serous adenocarcinoma (high grade, 33; low grade, 1). PFTC was classified into ampulla type, fimbriae type and undeterminable type by tumor-occupying lesion; ampulla type and fimbriae type occurred with the same frequency. Among 30 patients with high-grade serous adenocarcinoma, 6 patients showed germline mutations of BRCA1 (stop-gain 4 and frameshift deletion 2) and 2 patients showed germline mutation of BRCA2 (stop-gain 1 and frameshift deletion 1). However, only 1 patient had familial history of breast or ovarian cancer. Patients with BRCA mutations in the germline were frequently observed in ampulla type and FIGO stage I/II cancers, but no significant difference in the frequency of p53 overexpression and overall survival was observed.

Conclusions

Among Japanese patients with PFTC, 26.7% presented with BRCA mutations in the germline. Additionally, p53 was important for the carcinogenesis in fallopian tubes, independent of the specific BRCA mutation.

Fallopian Tube Lesions in Women at High Risk for Ovarian Cancer: A Multicenter Study

The prognosis of women diagnosed with invasive high-grade serous ovarian carcinoma (HGSC) is poor. More information about serous tubal intraepithelial carcinoma (STIC) and serous tubal intraepithelial lesions (STIL), putative precursor lesions of HGSC, could inform prevention efforts. We conducted a multicenter study to identify risk/protective factors associated with STIC/STILs and characterize p53 signatures in the fallopian tube. The fallopian tubes and ovaries of 479 high-risk women ≥30 years of age who underwent bilateral risk-reducing salpingo-oophorectomy were reviewed for invasive cancer/STICs/STILs. Epidemiologic data was available for 400 of these women. In 105 women, extensive sampling of the tubes for STICs/STILs/p53 signatures were undertaken. Descriptive statistics were used to compare groups with and without lesions. The combined prevalence of unique tubal lesions [invasive serous cancer (n = 6) /STICs (n = 14)/STILs (n = 5)] was 6.3% and this was split equally among BRCA1 (3.0%) and BRCA2 mutation carriers (3.3%). A diagnosis of invasive cancer was associated with older age but no risk/protective factor was significantly associated with STICs/STILs. Extensive sampling identified double the number of STICs/STILs (11.9%), many p53 signatures (27.0%), and multiple lesions in 50% of the cases. Women with p53 signatures in the fimbria were older than women with signatures in the remaining tube (P = 0.03). STICs/STILs may not share the protective factors that are associated with HGSC. It is plausible that these factors are only associated with STICs that progress to HGSC. Having multiple lesions in the fimbria may be an important predictor of disease progression. Cancer Prev Res; 11(11); 697-706. ©2018 AACR.

Fallopian Tube Lesions in Women at High Risk for Ovarian Cancer: A Multicenter Study

The prognosis of women diagnosed with invasive high-grade serous ovarian carcinoma (HGSC) is poor. More information about serous tubal intraepithelial carcinoma (STIC) and serous tubal intraepithelial lesions (STIL), putative precursor lesions of HGSC, could inform prevention efforts. We conducted a multicenter study to identify risk/protective factors associated with STIC/STILs and characterize p53 signatures in the fallopian tube. The fallopian tubes and ovaries of 479 high-risk women ≥30 years of age who underwent bilateral risk-reducing salpingo-oophorectomy were reviewed for invasive cancer/STICs/STILs. Epidemiologic data was available for 400 of these women. In 105 women, extensive sampling of the tubes for STICs/STILs/p53 signatures were undertaken. Descriptive statistics were used to compare groups with and without lesions. The combined prevalence of unique tubal lesions [invasive serous cancer (n = 6) /STICs (n = 14)/STILs (n = 5)] was 6.3% and this was split equally among BRCA1 (3.0%) and BRCA2 mutation carriers (3.3%). A diagnosis of invasive cancer was associated with older age but no risk/protective factor was significantly associated with STICs/STILs. Extensive sampling identified double the number of STICs/STILs (11.9%), many p53 signatures (27.0%), and multiple lesions in 50% of the cases. Women with p53 signatures in the fimbria were older than women with signatures in the remaining tube (P = 0.03). STICs/STILs may not share the protective factors that are associated with HGSC. It is plausible that these factors are only associated with STICs that progress to HGSC. Having multiple lesions in the fimbria may be an important predictor of disease progression. Cancer Prev Res; 11(11); 697-706. ©2018 AACR.

Bilateral salpingectomy to reduce the risk of ovarian/fallopian/peritoneal cancer in women at average risk: a position statement of the Korean Society of Obstetrics and Gynecology (KSOG)

Based on the current understanding of a preventive effect of bilateral salpingectomy on ovarian/fallopian/peritoneal cancers, the Korean Society of Obstetrics and Gynecology, Korean Society of Gynecologic Endocrinology, Korean Society of Gynecologic Oncology, Korean Society of Maternal Fetal Medicine, and Korean Society for Reproductive Medicine support the following recommendations: • Women scheduled for hysterectomy for benign gynecologic disease should be informed that bilateral salpingectomy reduces the risk of ovarian/fallopian/peritoneal cancer, and they should be counseled regarding this procedure at the time of hysterectomy. • Although salpingectomy is generally considered as a safe procedure in terms of preserving ovarian reserve, there is a lack of evidences representing its long-term outcomes. Therefore, patients should be informed about the minimal potential of this procedure for decreasing ovarian reserve. • Prophylactic salpingectomy during vaginal hysterectomy is favorable in terms of prevention of ovarian/fallopian/peritoneal cancer, although operation-related complications minimally increase with this procedure, compared to the complications associated with vaginal hysterectomy alone. Conversion to open or laparoscopic approach from vaginal approach to perform prophylactic salpingectomy is not recommended. • Women who desire permanent sterilization at the time of cesarean delivery could be counseled for prophylactic salpingectomy before surgery on an individual basis.

Inflammation is a key contributor to ovarian cancer cell seeding

The incidence of ovarian cancer dramatically increases in early menopause but the factors contributing to cancer onset are unclear. Most ovarian cancers originate in the fallopian tube with subsequent implantation of malignant cells into the ovary. However, the events and conditions that lead to cancer cell implantation are unknown. To quantify which conditions are conducive to the seeding of cancer cells in an immunocompetent mouse model, we surgically implanted mouse ovarian cancer cells into the oviducts of syngeneic mice and simulated conditions associated with ovulatory wound repair, incessant ovulation, ovarian surface scarring, and aging. We found that the dominant site of cancer cell seeding was not the ovary but the nearby surgical wound site, which was associated with a strong and persistent inflammatory reaction. Conditions in the ovary associated with inflammation, such as acute ovulatory wound repair, active healing of the scarred ovarian surface, and mouse aging, contributed to increased seeding of the cancer cells to the surgical wound site and tissues surrounding the ovary. Changes in the ovary not accompanied by inflammation, such as completed ovulatory cycles and fully-healed scars on the ovarian surface, did not contribute to increased cancer cell seeding. We conclude that inflammation is the most likely mechanism by which ovulation and postmenopausal events contribute to the increased risk of ovarian cancer.

Case for a role of the microbiome in gynecologic cancers: Clinician's perspective

In this review, we aimed to provide insight into the microbiome and its association with endometrial and ovarian cancer and their risk factors. We reviewed the literature focusing on the relationship between the microbiome and cancer, as well as the relationship between gynecologic diseases and cancers. The human body contains different kinds of microorganisms in various body parts, which is termed the microbiome. The number of microorganisms that live in and on the human body is greater than that of the human germ and somatic cells by 10-fold. The relationship between a human and their microbiome is complex; it is also one of the most important components of homeostasis. Impairment of microbiome-host homeostasis has been associated with obesity, several cancers, preterm labor, inflammatory and allergic conditions and neurodevelopmental disorders. Direct and strong causal relationships have been established for several cancers and microorganisms, such as gastric lymphoma and Helicobacter pylori infection. Interestingly, eradication of the infectious agents has also been shown to be therapeutic. The association between cancer and the microbiome, however, is more complicated than a 1 bacteria-1 cancer model, and a shift in a healthy microbiome can result in various cancers via inflammation, change in microenvironment or DNA-damaging toxins. The human microbiome is an integral part of homeostasis. Understanding the mechanisms that cause dysbiosis will enable us to elucidate the pathways that result in malignancy and investigate new treatment modalities.

Can Stemness and Chemoresistance Be Therapeutically Targeted via Signaling Pathways in Ovarian Cancer?

Ovarian cancer is the most lethal gynecological malignancy. Poor overall survival, particularly for patients with high grade serous (HGS) ovarian cancer, is often attributed to late stage at diagnosis and relapse following chemotherapy. HGS ovarian cancer is a heterogenous disease in that few genes are consistently mutated between patients. Additionally, HGS ovarian cancer is characterized by high genomic instability. For these reasons, personalized approaches may be necessary for effective treatment and cure. Understanding the molecular mechanisms that contribute to tumor metastasis and chemoresistance are essential to improve survival rates. One favored model for tumor metastasis and chemoresistance is the cancer stem cell (CSC) model. CSCs are cells with enhanced self-renewal properties that are enriched following chemotherapy. Elimination of this cell population is thought to be a mechanism to increase therapeutic response. Therefore, accurate identification of stem cell populations that are most clinically relevant is necessary. While many CSC identifiers (ALDH, OCT4, CD133, and side population) have been established, it is still not clear which population(s) will be most beneficial to target in patients. Therefore, there is a critical need to characterize CSCs with reliable markers and find their weaknesses that will make the CSCs amenable to therapy. Many signaling pathways are implicated for their roles in CSC initiation and maintenance. Therapeutically targeting pathways needed for CSC initiation or maintenance may be an effective way of treating HGS ovarian cancer patients. In conclusion, the prognosis for HGS ovarian cancer may be improved by combining CSC phenotyping with targeted therapies for pathways involved in CSC maintenance.

Processing of fallopian tube, ovary, and endometrial surgical pathology specimens: A survey of U.S. laboratory practices

OBJECTIVE

Many high-grade serous carcinomas initiate in fallopian tubes as serous tubal intraepithelial carcinoma (STIC), a microscopic lesion identified with specimen processing according to the Sectioning and Extensive Examination of the Fimbria protocol (SEE-Fim). Given that the tubal origin of these cancers was recently recognized, we conducted a survey of pathology practices to assess processing protocols that are applied to gynecologic surgical pathology specimens in clinical contexts in which finding STIC might have different implications.

METHODS

We distributed a survey electronically to the American Society for Clinical Pathology list-serve to determine practice patterns and compared results between practice types by chi-square (χ2) tests for categorical variables. Free text comments were qualitatively reviewed.

RESULTS

Survey responses were received from 159 laboratories (72 academic, 87 non-academic), which reported diverse specimen volumes and percentage of gynecologic samples. Overall, 74.1% of laboratories reported performing SEE-Fim for risk-reducing surgical specimens (82.5% academic versus 65.7% non-academic, p < 0.05). In specimens from surgery for benign indications in which initial microscopic sections showed an unanticipated suspicious finding, 75.9% of laboratories reported using SEE-Fim to process the remainder of the specimen (94.8% academic versus 76.4% non-academic, p < 0.01), and 84.6% submitted the entire fimbriae.

CONCLUSIONS

Changes in the theories of pathogenesis of high-grade serous carcinoma have led to implementation of pathology specimen processing protocols that include detailed analysis of the fallopian tubes. These results have implications for interpreting trends in cancer incidence data and considering the feasibility of developing a bank of gynecologic tissues containing STIC or early cancer precursors.

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.

Pathology of Ovarian Cancer: Recent Insights Unveiling Opportunities in Prevention

Ovarian carcinomas were formerly referred to as "surface epithelial carcinomas," reflecting the belief that they all arise from the ovarian surface epithelium. It is now appreciated that most ovarian carcinomas originate from either fallopian tube or endometriotic epithelium, and how we approach prevention will thus differ between histotypes. The 5 histotypes of ovarian carcinoma (high-grade serous, clear cell, endometrioid, mucinous, and low-grade serous, in descending order of frequency) can be reproducibly diagnosed, and are distinct disease entities, differing with respect to genetic risk factors, molecular events during oncogenesis, patterns of spread, and response to chemotherapy.

Origins based clinical and molecular complexities of epithelial ovarian cancer

Ovarian cancer is the most lethal of all common gynaecological malignancies in women worldwide. Ovarian cancer comprises of >15 distinct tumor types and subtypes characterized by histopathological features, environmental and genetic risk factors, precursor lesions and molecular events during oncogenesis. Recent studies on gene signature profiling of different subtypes of ovarian cancer have revealed significant genetic heterogeneity between and within each ovarian cancer histological subtype. Thus, an immense interest have shown towards a more personalized medicine for understanding the clinical and molecular complexities of four major types of epithelial ovarian cancer (serous, endometrioid, clear cell, and mucinous). As such, further in depth studies are needed for identification of molecular signalling network complexities associated with effective prognostication and targeted therapies to prevent or treat metastasis. Therefore, understanding the metastatic potential of primary ovarian cancer and therapeutic interventions against lethal ovarian cancer for the development of personalized therapies is very much indispensable. Consequently, in this review we have updated the key dysregulated genes of four major subtypes of epithelial carcinomas. We have also highlighted the recent advances and current challenges in unravelling the complexities of the origin of tumor as well as genetic heterogeneity of ovarian cancer.

Multicenter Clinicopathological Study of High-Grade Serous Carcinoma Presenting as Primary Peritoneal Carcinoma

OBJECTIVE

We conducted a multicenter clinicopathological study to characterize patients with high-grade serous carcinoma presenting as primary peritoneal carcinoma (clinical PPC).

METHODS

At 9 sites in Japan, patients with clinical PPC diagnosed according to Gynecologic Oncology Group criteria were enrolled retrospectively. The Gynecologic Oncology Group criteria allow for minor ovarian involvement by high-grade serous carcinoma. There was no systematic detailed histopathological review of the fallopian tubes to determine whether they were involved by serous carcinoma.

RESULTS

There were 139 patients and 64% were aged 60 years or older. Median pretreatment serum CA-125 was 1653.5 IU/mL. Pretreatment performance status was poor in more than 50%, endometrial cytology was positive in 40.3%, and the preoperative clinical diagnosis was correct in 72.7%. Primary debulking surgery was performed in 36% of patients, whereas 64% underwent neoadjuvant chemotherapy (NAC) with interval debulking surgery (IDS). The main tumor sites were the upper abdomen (greater omentum), extrapelvic peritoneum, mesentery, and diaphragm. Lymph node metastasis was found in 46.8% of patients undergoing systematic retroperitoneal node dissection. The optimal surgery rate was 32.0% with primary debulking surgery versus 53.9% with NAC and IDS (P = 0.0139). The response rate was 82.0% with NAC and 80.6% with postoperative chemotherapy. Median progression-free survival was 19.0 months and median overall survival was 41.0 months. Multivariate analysis showed that prognostic factors for progression-free survival were NAC and residual tumor diameter after debulking surgery, whereas the only prognostic factor for overall survival was the residual tumor diameter.

CONCLUSIONS

This study identified various characteristics of clinical PPC. Neoadjuvant chemotherapy with IDS is a reasonable treatment strategy, and complete debulking surgery is optimum.

Extrauterine high-grade serous carcinomas with bilateral adnexal involvement as the only two disease sites are clonal based on tp53 sequencing results: implications for biology, classification, and staging

A previous multicenter study of 67 cases of Stage I/II tubo-ovarian high-grade serous carcinoma with complete tubal sampling identified 7 cases in which there were only two disease sites, comprising tumor involving opposite adnexa with no extra-adnexal involvement. This study aimed to determine whether such low-stage extrauterine high-grade serous carcinomas with only two sites of involvement, located on opposite adnexa, have identical or different TP53 mutations in order to investigate their clonal relationship. DNA extracted from both sites of involvement was subjected to TP53 sequencing (n=6) or sequencing of one site and mutation confirmation by droplet digital PCR for the other site (n=1). Of the 7 cases analyzed, 1 case had unilateral serous tubal intraepithelial carcinoma with contralateral ovarian high-grade serous carcinoma, 3 had tubal high-grade serous carcinomas (±serous tubal intraepithelial carcinoma) with contralateral ovarian high-grade serous carcinoma, 2 had bilateral ovarian high-grade serous carcinomas with normal tubes, and 1 had bilateral fallopian tube high-grade serous carcinoma with normal ovaries. All 7 cases showed identical TP53 mutations in tumor from both disease sites. Therefore, these rare cases of high-grade serous carcinoma confined to opposite adnexa all show clonal identity between the two sites of involvement, suggesting unifocal origin and metastasis rather than multifocal origin. Our results suggest that serous tubal intraepithelial carcinoma or adnexal high-grade serous carcinoma can metastasize to the contralateral adnexa without peritoneal involvement. Given the clonal relationship between the two sites, such cases should be considered stage II, with stage I reserved for cases with unilateral and unifocal adnexal involvement. Furthermore, serous tubal intraepithelial carcinoma without invasion should be taken to constitute a disease site for staging purposes.

Screening for ovarian cancer: imaging challenges and opportunities for improvement

The United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) recently reported a reduction in the average overall mortality among ovarian cancer patients screened with an annual sequential, multimodal strategy that tracked biomarker CA125 over time, where increasing serum CA125 levels prompted ultrasound. However, multiple cases were documented wherein serum CA125 levels were rising, but ultrasound screens were normal, thus delaying surgical intervention. A significant factor which could contribute to false negatives is that many aggressive ovarian cancers are believed to arise from epithelial cells on the fimbriae of the fallopian tubes, which are not readily imaged. Moreover, because only a fraction of metastatic tumors may reach a sonographically-detectable size before they metastasize, annual screening with ultrasound may fail to detect a large fraction of early-stage ovarian cancers. The ability to detect ovarian carcinomas before they metastasize is critical and future efforts towards improving screening should focus on identifying unique features specific to aggressive, early-stage tumors, as well as improving imaging sensitivity to allow for detection of tubal lesions. Implementation of a three-stage multimodal screening strategy in which a third modality is employed in cases where the first-line blood-based assay is positive and the second-line ultrasound exam is negative may also prove fruitful in detecting early-stage cases missed by ultrasound.

PTEN loss in the fallopian tube induces hyperplasia and ovarian tumor formation

The signaling events involved in the onset of ovarian cancer from the fallopian tube epithelium (FTE) are crucial for early detection and treatment of the disease, but they remain poorly defined. Conditional homozygous knockout of PTEN mediated by PAX8-cre recombinase was sufficient to drive endometrioid and serous borderline ovarian carcinoma, providing the first model of FTE-derived borderline tumors. In addition, heterozygous PTEN deletion in the FTE resulted in hyperplasia, providing a model to study early events of human ovarian pathogenesis. To uncover the mechanism underlying the invasion of cancerous oviductal cells to the ovary, PTEN-deficient murine oviductal cells were developed and tagged with green fluorescent protein. Loss of PTEN increased cell migration, invasion, and upregulated WNT4, a key regulator of Müllerian duct development during embryogenesis. Further investigation revealed that WNT4 was required for increased migration and colonization of the ovary by PTEN-deficient oviductal cells in a β-catenin independent manner. Human tumor microarrays and ovarian cancer cells lines confirmed WNT4 expression in cancer and its role in migration. Together, these findings provide a novel model to study the mechanism of fallopian tube tumor initiation and invasion to the ovary mediated by loss of PTEN, which may help to define early events of human ovarian carcinogenesis.

Efficacy and safety of dose-dense paclitaxel plus carboplatin as neoadjuvant chemotherapy for advanced ovarian, fallopian tube or peritoneal cancer

Objective

Interval debulking surgery (IDS) after neoadjuvant chemotherapy (NAC) is currently one of the preferred treatment options for advanced ovarian, fallopian tube or peritoneal cancer. This study was conducted to evaluate the clinical efficacy and safety of dose-dense paclitaxel plus carboplatin therapy (ddTC therapy) as NAC for these cancers.

Patients and methods

A retrospective study was conducted in 25 patients with Stage III/IV ovarian, fallopian tube or peritoneal cancer who received ddTC therapy as NAC. For ddTC therapy, paclitaxel (80 mg/m2) was administered intravenously on Days 1, 8 and 15 and carboplatin (AUC 6.0 mg/ml × min) was administered intravenously on Day 1 every 3 weeks. IDS was performed after three cycles of ddTC therapy, and ddTC therapy was also continued after surgery.

Results

With ddTC therapy as NAC, the response rate was 92% and disease progression did not occur in any patient. Grade 4 hematologic toxicity and ≥Grade 3 non-hematologic toxicity both occurred in 8% of the patients, but no patient discontinued NAC because of adverse events. When IDS was performed, the complete surgery rate was 64% and the optimal surgery rate was 96%. ≥Grade 3 perioperative complications occurred in 16% of the patients, but there were no perioperative deaths. Median overall survival was 35.7 months and median progression-free survival was 17.7 months.

Conclusion

This study showed that ddTC therapy was considerably effective and tolerable as NAC. The complete surgery rate was high with IDS, and perioperative complications were acceptable.

Pathogenesis and heterogeneity of ovarian cancer

PURPOSE OF REVIEW

The most common type of ovarian cancer, high-grade serous ovarian carcinoma (HGSOC), was originally thought to develop from the ovarian surface epithelium. However, recent data suggest that the cells that undergo neoplastic transformation and give rise to the majority of HGSOC are from the fallopian tube. This development has impacted both translational research and clinical practice, revealing new opportunities for early detection, prevention, and treatment of ovarian cancer.

RECENT FINDINGS

Genomic studies indicate that approximately 50% of HGSOC are characterized by mutations in genes involved in the homologous recombination pathway of DNA repair, especially BRCA1 and BRCA2. Clinical trials have demonstrated successful treatment of homologous recombination-defective cancers with poly-ribose polymerase inhibitors through synthetic lethality. Recently, amplification of CCNE1 was found to be another major factor in HGSOC tumorigenesis, accounting for approximately 20% of all cases. Interestingly, amplification of CCNE1 and mutation of homologous recombination repair genes are mutually exclusive in HGSOC.

SUMMARY

The fallopian tube secretory cell is the cell of origin for the majority of ovarian cancers. Although it remains unclear what triggers neoplastic transformation of these cells, certain tumors exhibit loss of BRCA function or amplification of CCNE1. These alterations represent unique therapeutic opportunities in ovarian cancer.

Reconstitution of high-grade serous ovarian carcinoma from primary fallopian tube secretory epithelial cells

Fallopian tube secretory epithelial cells (FTSECs) have been suggested to be the source of high-grade serous ovarian carcinoma (HGSOC). Although several genetic alterations are known to be involved in HGSOC development, the minimal requirements remain unclear. We aimed to identify oncogenic mutations indispensable for HGSOC development in a stepwise model, using immortalized FTSECs. FTSECs were isolated from clinical samples and immortalized by overexpression of cyclin D1, CDK4^R24C, and hTERT. Oncogenic mutations in the p53, c-Myc, and RAS/PI3K pathways were mimicked by lentiviral transduction. We found two distinct patterns of gene alteration essential for HGSOC development: p53/KRAS/AKT and p53/KRAS/c-Myc. Dominant-negative p53, alone or combined with oncogenic KRAS (KRASV12), constitutively active AKT (CA-AKT), and c-Myc, did not induce tumorigenesis in immortalized cells; however, overexpression of CA-AKT or c-Myc, along with dominant-negative p53 and KRASV12, conferred tumorigenic potential. Transformed FTSECs formed tumors in nude mice that were grossly, histologically, and immunohistochemically similar to human HGSOCs. Interestingly, mice harboring tumors with c-Myc amplifications displayed extensive metastases, consistent with the increased dissemination in their human counterparts. Thus, aberrant p53/KRASV12/c-Myc or p53/KRASV12/PI3K-AKT signaling was the minimum requirement for FTSEC carcinogenesis. The model based on this evidence could shed light on the early stages of HGSOC development.