Low-grade serous carcinoma of the ovary or peritoneum

Primary ovarian cancer combined with primary fallopian tube cancer: A case report

BACKGROUND

Low grade serous carcinoma of the ovary (LGSOC) is a rare type of epithelial ovarian cancer with a low incidence rate. The origin of ovarian cancer has always been a hot topic in gynecological oncology research, and some scholars believe that the origin of ovarian malignant tumors is the fallopian tubes. Primary fallopian tube cancer is the lowest incidence of malignant tumors in the female reproductive system. There are only a few reports in the literature, but the mortality rate is very high. But in clinical practice, fallopian tube cancer is very common, but in most cases, it is classified as ovarian cancer.

CASE SUMMARY

We report a 54 years old postmenopausal woman who was hospitalized with a lower abdominal mass and underwent surgical treatment. The final pathological confirmation was low-grade serous carcinoma of the right ovary and low-grade serous carcinoma of the left fallopian tube. No special treatment was performed after the surgery, and the patient was instructed to undergo regular follow-up without any signs of disease progression.

CONCLUSION

The prognosis of LGSOC is relatively good, over 80% of patients still experience disease recurrence.

Advances in precision therapy of low-grade serous ovarian cancer: A review

Low-grade serous ovarian carcinoma (LGSOC) is a rare subtype of ovarian cancer that accounts for approximately 6% to 10% of serous ovarian cancers. The clinical treatment of LGSOC is similar to that of high-grade serous ovarian carcinoma, however, its clinical and molecular characteristics are different from those of high-grade serous ovarian carcinoma. This article reviews the research on gene diagnosis, surgical treatment, chemotherapy, and biological therapy of LGSOC, providing reference for clinical diagnosis and treatment of LGSOC. Surgery is the cornerstone of LGSOC treatment and maximum effort must be made to achieve R0 removal. Although LGSOC is not sensitive to chemotherapy, postoperative platinum-based combination chemotherapy remains the first-line treatment option for LGSOC. Additional clinical trials are needed to confirm the clinical benefits of chemotherapy and explore new chemotherapy protocols. Hormone and targeted therapies may also play important roles. Some patients, particularly those with residual lesions after treatment, may benefit from hormone maintenance therapy after chemotherapy. Targeted therapies, such as MEKi, show good application prospects and are expected to change the treatment pattern of LGSOC. Continuing to further study the genomics of LGSOC, identify its specific gene changes, and combine traditional treatment methods with precision targeted therapy based on second-generation sequencing may be the direction for LGSOC to overcome the treatment bottleneck. In future clinical work, comprehensive genetic testing should be carried out for LGSOC patients to accumulate data for future scientific research, in order to find more effective methods and drugs for the treatment of LGSOC.

Clinical Observations and Outcomes in Advanced Low-Grade Serous Carcinoma of the Ovary: Case Series from a Tertiary Cancer Center

Low-grade serous carcinoma (LGSC) is a rare histologic subtype of ovarian cancer. We present detailed management of 15 cases of advanced LGSC from a tertiary cancer center of India. Fifteen cases of advanced LGSC who underwent cytoreductive surgery (CRS) were analyzed from a prospectively maintained database. Baseline demographic characteristics, surgical details, and chemotherapy details were recorded. Descriptive statistics were summarized, and progression-free survival (PFS) and overall survival (OS) were estimated. The median age was 37 years. Nine patients had received NACT. All cases were FIGO stage III. Mean PCI was 15. Eleven patients had a completeness of cytoreduction score of 0-1. The median surgical time was 7.5 h; nine patients required multiple gastrointestinal resections. Median blood loss was 2500 ml. Median postoperative ventilation, ICU stay, and hospital stays were 1, 2, and 16 days, respectively. One patient had a grade III complication. Four patients received adjuvant chemotherapy. There was no postoperative mortality at the end of 90 days of surgery. All the patients except one were offered hormonal maintenance therapy. At a median follow-up of 43 months, 4 patients were disease-free, 9 had a recurrence, one died of disease progression, and one was lost to follow-up. Most recurrences were locoregional in the peritoneal cavity or pelvis. Four-year OS and PFS were 71.8% and 29.7%, respectively. Advanced LGSCs occur mostly in young premenopausal women with favorable oncologic outcomes. Optimal CRS is the mainstay of treatment. Relative chemo-resistance and hormone receptor positivity provide an excellent therapeutic opportunity for endocrine therapy.

Metastasis of ovarian cancer to nasal skin and skin on the trunk: a rare case report

Cutaneous metastases of ovarian cancer are rare and often have poor prognosis. We report a case of a 62-year-old woman with recurrent low-grade serous ovarian cancer, who presented with lung, brain, and multiple skin (nasal and anterior chest wall) metastases approximately six months after the initial diagnosis. In this case, Nijmegen breakage syndrome carrier status caused by RAD50 heterozygous mutation and previous bevacizumab therapy could be the predisposing factor for cutaneous metastases. The patient was treated with local radiotherapy (nasal skin and brain, 30Gy/6f/1.2W) and three courses of chemotherapy with albumin-bound paclitaxel and carboplatin, resulting in drastic remission of the cutaneous metastases. Unfortunately, treatment interruption resulted in rapid tumor progression, followed by death. This case represents an interesting example of cutaneous metastasis of ovarian cancer with rare clinical manifestations, unique genetic mutations, and reasonable response to treatment. Chemoradiotherapy might be an appropriate option for cutaneous metastases of ovarian cancer. Nevertheless, we still hope to find out the best treatment strategy after collecting and reviewing more cases in the future.

Molecular Results and Potential Biomarkers Identified from the Phase 3 MILO/ENGOT-ov11 Study of Binimetinib versus Physician Choice of Chemotherapy in Recurrent Low-Grade Serous Ovarian Cancer

PURPOSE

We present the results of a post hoc tumor tissue analysis from the phase 3 MILO/ENGOT-ov11 study (NCT01849874).

PATIENTS AND METHODS

Mutation/copy-number analysis was performed on tissue obtained pre-randomization. The Kaplan-Meier method was used to estimate progression-free survival (PFS). Unbiased univariate analysis, Cox regression, and binary logistic regression were used to test associations between mutation status and outcomes, including PFS and binary response by local RECIST 1.1.

RESULTS

MILO/ENGOT-ov11 enrolled 341 patients, ranging in age from 22 to 79, from June, 2013 to April, 2016. Patients were randomized 2:1 to binimetinib or physician's choice of chemotherapy (PCC). The most commonly altered gene was KRAS (33%). In 135 patients treated with binimetinib with response rate (RR) data, other detected MAPK pathway alterations included: NRAS (n = 11, 8.1%), BRAF V600E (n = 8, 5.9%), RAF1 (n = 2, 1.5%), and NF1 (n = 7, 5.2%). In those with and without MAPK pathway alterations, the RRs with binimetinib were 41% and 13%, respectively. PFS was significantly longer in patients with, compared with those without, MAPK pathway alterations treated with binimetinib [HR, 0.5; 95% confidence interval (CI) 0.31-0.79]. There was a nonsignificant trend toward PFS improvement in PCC-treated patients with MAPK pathway alterations compared with those without (HR, 0.82; 95% CI, 0.43-1.59).

CONCLUSIONS

Although this hypothesis-generating analysis is limited by multiple testing, higher RRs and longer PFS were seen in patients with low-grade serous ovarian cancer (LGSOC) treated with binimetinib, and to a lesser extent in those treated with PCC, who harbored MAPK pathway alterations. Somatic tumor testing should be routinely considered in patients with LGSOC and used as a future stratification factor.

Low-grade serous ovarian cancer: expert consensus report on the state of the science

Compared with high-grade serous carcinoma, low-grade serous carcinoma of the ovary or peritoneum is a less frequent epithelial ovarian cancer type that is poorly sensitive to chemotherapy and affects younger women, many of whom endure years of ineffective treatments and poor quality of life. The pathogenesis of this disease and its management remain incompletely understood. However, recent advances in the molecular characterization of the disease and identification of novel targeted therapies with activity in low-grade serous carcinoma offer the promise of improved outcomes. To update clinicians regarding recent scientific and clinical trial advancements and discuss unanswered questions related to low-grade serous carcinoma diagnosis and treatment, a panel of experts convened for a workshop in October 2022 to develop a consensus document addressing pathology, translational research, epidemiology and risk, clinical management, and ongoing research. In addition, the patient perspective was discussed. The recommendations developed by this expert panel-presented in this consensus document-will guide practitioners in all settings regarding the clinical management of women with low-grade serous carcinoma and discuss future opportunities to improve research and patient care.

Bevacizumab Treatment for Low-Grade Serous Ovarian Cancer: A Systematic Review

Serous epithelial ovarian cancer, classified as either high-grade (90%) or low-grade (10%), varies in molecular, histological, and clinicopathological presentation. Low-grade serous ovarian cancer (LGSOC) is a rare histologic subtype that lacks disease-specific evidence-based treatment regimens. However, LGSOC is relatively chemo-resistant and has a poor response to traditional treatments. Alternative treatments, including biologic therapies such as bevacizumab, have shown some activity in LGSOC. Thus, the objective of this systematic review is to determine the effect and safety of bevacizumab in the treatment of LGSOC. Following PRISMA guidelines, Medline ALL, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Embase all from the OvidSP platform, ClinicalTrials.gov, International Clinical Trials Registry Platform, International Standard Randomised Controlled Trial Number Registry were searched from inception to February 2022. Articles describing bevacizumab use in patients with LGSOC were included. Article screening, data extraction, and critical appraisal of included studies were completed by two independent reviewers. The effect of bevacizumab on the overall response rate, progression-free survival, overall survival, and adverse effects were summarized. The literature search identified 3064 articles, 6 of which were included in this study. A total of 153 patients were analyzed; the majority had stage IIIC cancer (56.2%). The overall median response rate reported in the studies was 47.5%. Overall, bevacizumab is a promising treatment for LGSOC, with response rates higher than traditional treatment modalities such as conventional chemotherapy, and is often overlooked as a treatment tool. A prospective clinical trial evaluating the use of bevacizumab in LGSOC is necessary to provide greater evidence and support these findings.

Rare Epithelial Ovarian Cancers: Low Grade Serous and Mucinous Carcinomas

The ovarian epithelial cancer histotypes can be divided into common and rare types. Common types include high-grade serous ovarian carcinomas and the endometriosis-associated cancers, endometrioid and clear-cell carcinomas. The less common histotypes are mucinous and low-grade serous, each comprising less than 10% of all epithelial carcinomas. Although histologically and epidemiologically distinct from each other, these histotypes share some genetic and natural history features that distinguish them from the more common types. In this review, we will consider the similarities and differences of these rare histological types, and the clinical challenges they pose.

The highs and lows of serous ovarian cancer

Low-grade serous ovarian cancer was initially described as a distinct type of rare epithelial ovarian cancer 20 years ago; however, only recently have physicians begun to leverage the understanding of the clinical behavior and molecular profile of this disease for treatment. The use of routine next-generation sequencing has allowed a deeper understanding of the molecular drivers of this disease and shown how molecular alterations in mitogen-activated protein kinase pathway genes such as KRAS and BRAF can affect overall prognosis and disease behavior. The use of targeted therapies, including MEK inhibitors, BRAF kinase inhibitors, and other investigational targeted therapies are changing the way this disease is viewed and treated. In addition, endocrine therapy can provide prolonged disease stability with generally mild toxicity, as well as promising response rates in recent studies examining combination therapy with CDK 4/6 inhibitors in the upfront and recurrent setting. Once seen merely as a chemo-resistant form of ovarian cancer, recent studies have worked to harness the unique features of low-grade serous ovarian cancer to provide individualized treatment options for patients with this disease.

Molecular characteristics of low-grade serous carcinoma in effusions

OBJECTIVE

The molecular characteristics of low-grade serous carcinoma (LGSC) in serous effusions have not been studied previously. The present study analysed the molecular profile of LGSC at this anatomical site.

METHODS

Specimens consisted of a series of 17 serous effusions (15 peritoneal, 2 pleural) from 16 patients, of which 15 were LGSC and 2 serous borderline tumour (SBT) who later progressed to LGSC. For comparative purposes, 9 surgical specimens from 6 patients with LGSC were analysed. Fresh-frozen cell pellets and surgical specimens underwent targeted next-generation sequencing covering 50 unique genes.

RESULTS

Mutations were found in tumours from 14 of the 22 patients, of whom 4 had 2 different mutations and 10 had a single mutation. Overall, the most common mutations were in KRAS (n = 3) and BRAF (n = 3), followed by NRAS (n = 2), CDK2NA (n = 2), TP53 (n = 2), ATM (n = 2). Mutations in MET, STK11, ERBB2 and FLT3 were found in one case each. Patient-matched specimens had the same molecular profile. Both effusions with TP53 mutation had concomitant ATM mutation, and both stained immunohistochemically with a wild-type pattern. The absence of mutations was associated with a trend for shorter overall survival in univariate analysis (p = 0.072).

CONCLUSIONS

The molecular alterations in LGSCs in serous effusions are consistent with those found in solid tumours, with frequent alterations in the mitogen-activated protein kinase pathway. Mutations in LGSC may be a marker of better outcomes.

Molecular mechanism of Wilms' tumor (Wt1) (+/-KTS) variants promoting proliferation and migration of ovarian epithelial cells by bioinformatics analysis

Epithelial ovarian cancer (EOC) is a gynecological disease with the highest mortality. With the lack of understanding of its pathogenesis, no accurate early diagnosis and screening method has been established for EOC. Studies revealed the multi-faceted function of Wilms' tumor (Wt1) genes in cancer, which may be related to the existence of multiple alternative splices. Our results show that Wt1 (+KTS) or Wt1 (-KTS) overexpression can significantly promote the proliferation and migration of human ovarian epithelial cells HOSEpiC, and Wt1 (+KTS) effects were more evident. To explore the Wt1 (+/-KTS) variant mechanism in HOSEpiC proliferation and migration and ovarian cancer (OC) occurrence and development, this study explored the differential regulation of Wt1 (+/-KTS) in HOSEpiC proliferation and migration by transcriptome sequencing. OC-related hub genes were screened by bioinformatics analysis to further explore the differential molecular mechanism of Wt1 (+/-KTS) in the occurrence of OC. Finally, we found that the regulation of Wt1 (+/-KTS) variants on the proliferation and migration of HOSEpiC may act through different genes and signaling pathways and screened out key genes and differentially regulated genes that regulate the malignant transformation of ovarian epithelial cells. The implementation of this study will provide new clues for the early diagnosis and precise treatment of OC.

The adaptor protein VEPH1 interacts with the kinase domain of ERBB2 and impacts EGF signaling in ovarian cancer cells

Upregulation of ERBB2 and activating mutations in downstream KRAS/BRAF and PIK3CA are found in several ovarian cancer histotypes. ERBB2 enhances signaling by the ERBB family of EGF receptors, and contains docking positions for proteins that transduce signaling through multiple pathways. We identified the adaptor protein ventricular zone-expressed pleckstrin homology domain-containing protein 1 (VEPH1) as a potential interacting partner of ERBB2 in a screen of proteins co-immunoprecipitated with VEPH1. In this study, we confirm a VEPH1 - ERBB2 interaction by co-immunoprecipitation and biotin proximity labelling and show that VEPH1 interacts with the juxtamembrane-kinase domain of ERBB2. In SKOV3 ovarian cancer cells, which bear a PIK3CA mutation and ERBB2 overexpression, ectopic VEPH1 expression enhanced EGF activation of ERK1/2, and mTORC2 activation of AKT. In contrast, in ES2 ovarian cancer cells, which bear a BRAF^V600E mutation with VEPH1 amplification but low ERBB2 expression, loss of VEPH1 expression enabled further activation of ERK1/2 by EGF and enhanced EGF activation of AKT. VEPH1 expression in SKOV3 cells enhanced EGF-induced cell migration consistent with increased Snail2 and decreased E-cadherin levels. In comparison, loss of VEPH1 expression in ES2 cells led to decreased cell motility independent of EGF treatment despite higher levels of N-cadherin and Snail2. Importantly, we found that loss of VEPH1 expression rendered ES2 cells less sensitive to BRAF and MEK inhibition. This study extends the range of adaptor function of VEPH1 to ERBB2, and indicates VEPH1 has differential effects on EGF signaling in ovarian cancer cells that may be influenced by driver gene mutations.

Stage, treatment and survival of low-grade serous ovarian carcinoma in the Netherlands: A nationwide study

INTRODUCTION

Serous ovarian carcinomas constitute the largest group of epithelial ovarian cancer (60%-75%) and are further classified into high- and low-grade serous carcinoma. Low-grade serous carcinoma (LGSC) is a relatively rare subtype (approximately 5% of serous carcinomas) and epidemiologic studies of large cohorts are scarce. With the present study we aimed to report trends in stage, primary treatment and relative survival of LGSC of the ovary in a large cohort of patients in an effort to identify opportunities to improve clinical practice and outcome of this relatively rare disease.

MATERIAL AND METHODS

Patients diagnosed with LGSC between 2000 and 2019 were identified from the Netherlands Cancer Registry (n = 855). Trends in FIGO stages and primary treatment were analyzed with the Cochran-Armitage trend test, and differences in and trends of 5-year relative survival were analyzed using multivariable Poisson regression.

RESULTS

Over time, LGSC was increasingly diagnosed as stage III (39.9%-59.0%) and IV disease (5.7%-14.4%) and less often as stage I (34.6%-13.5%; p < 0.001). Primary debulking surgery was the most common strategy (76.2%), although interval debulking surgery was preferred more often over the years (10.6%-31.1%; p < 0.001). Following primary surgery, there was >1 cm residual disease in only 15/252 patients (6%), compared with 17/95 patients (17.9%) after interval surgery. Full cohort 5-year survival was 61% and survival after primary debulking surgery was superior to the outcome following interval debulking surgery (60% vs 34%). Survival following primary debulking surgery without macroscopic residual disease (73%) was better compared with ≤1 cm (47%) and >1 cm residual disease (22%). Survival following interval debulking surgery without macroscopic residual disease (51%) was significantly higher than after >1 cm residual disease (24%). Except FIGO stage II (85%-92%), survival did not change significantly over time.

CONCLUSIONS

Over the years, LGSC has been diagnosed as FIGO stage III and stage IV disease more often and interval debulking surgery has been increasingly preferred over primary debulking in these patients. Relative survival did not change over time (except for stage II) and worse survival outcomes after interval debulking surgery were observed. The results support the common recommendation to perform primary debulking surgery in patients eligible for primary surgery.

Drug response profiles in patient-derived cancer cells across histological subtypes of ovarian cancer: real-time therapy tailoring for a patient with low-grade serous carcinoma

Many efforts are underway to develop novel therapies against the aggressive high-grade serous ovarian cancers (HGSOCs), while our understanding of treatment options for low-grade (LGSOC) or mucinous (MUCOC) of ovarian malignancies is not developing as well. We describe here a functional precision oncology (fPO) strategy in epithelial ovarian cancers (EOC), which involves high-throughput drug testing of patient-derived ovarian cancer cells (PDCs) with a library of 526 oncology drugs, combined with genomic and transcriptomic profiling. HGSOC, LGSOC and MUCOC PDCs had statistically different overall drug response profiles, with LGSOCs responding better to targeted inhibitors than HGSOCs. We identified several subtype-specific drug responses, such as LGSOC PDCs showing high sensitivity to MDM2, ERBB2/EGFR inhibitors, MUCOC PDCs to MEK inhibitors, whereas HGSOCs showed strongest effects with CHK1 inhibitors and SMAC mimetics. We also explored several drug combinations and found that the dual inhibition of MEK and SHP2 was synergistic in MAPK-driven EOCs. We describe a clinical case study, where real-time fPO analysis of samples from a patient with metastatic, chemorefractory LGSOC with a CLU-NRG1 fusion guided clinical therapy selection. fPO-tailored therapy with afatinib, followed by trastuzumab and pertuzumab, successfully reduced tumour burden and blocked disease progression over a five-year period. In summary, fPO is a powerful approach for the identification of systematic drug response differences across EOC subtypes, as well as to highlight patient-specific drug regimens that could help to optimise therapies to individual patients in the future.

NOTCH Signaling Limits the Response of Low-Grade Serous Ovarian Cancers to MEK Inhibition

Low-grade serous ovarian cancer (LGSOC) is a rare subtype of epithelial ovarian cancer with high fatality rates in advanced stages due to its chemoresistant properties. LGSOC is characterized by activation of MAPK signaling, and recent clinical trials indicate that the MEK inhibitor (MEKi) trametinib may be a good treatment option for a subset of patients. Understanding MEKi-resistance mechanisms and subsequent identification of rational drug combinations to suppress resistance may greatly improve LGSOC treatment strategies. Both gain-of-function and loss-of-function CRISPR-Cas9 genome-wide libraries were used to screen LGSOC cell lines to identify genes that modulate the response to MEKi. Overexpression of MAML2 and loss of MAP3K1 were identified, both leading to overexpression of the NOTCH target HES1, which has a causal role in this process as its knockdown reversed MEKi resistance. Interestingly, increased HES1 expression was also observed in selected spontaneous trametinib-resistant clones, next to activating MAP2K1 (MEK1) mutations. Subsequent trametinib synthetic lethality screens identified SHOC2 downregulation as being synthetic lethal with MEKis. Targeting SHOC2 with pan-RAF inhibitors (pan-RAFis) in combination with MEKi was effective in parental LGSOC cell lines, in MEKi-resistant derivatives, in primary ascites cultures from patients with LGSOC, and in LGSOC (cell line-derived and patient-derived) xenograft mouse models. We found that the combination of pan-RAFi with MEKi downregulated HES1 levels in trametinib-resistant cells, providing an explanation for the synergy that was observed. Combining MEKis with pan-RAFis may provide a promising treatment strategy for patients with LGSOC, which warrants further clinical validation.

Genomic profiling in low grade serous ovarian cancer: Identification of novel markers for disease diagnosis and therapy

OBJECTIVES

Low grade serous ovarian cancer (LGSOC) differs from high grade serous in terms of pathogenesis, molecular, genetic, and clinical features. Molecular studies have been hampered by small sample sizes, heterogenous histology, and lack of comprehensive testing. We sought to molecularly profile LGSOC in a homogenously tested, histologically confirmed cohort.

METHODS

Using hot-spot and whole exome next generation sequencing (NGS), fusion gene analysis interrogating RNA, fragment analysis, in situ hybridization and/or immunohistochemistry, 179 specimens were evaluated by Caris Life Sciences (Phoenix, AZ). A second independent histologic review confirmed histology in 153 specimens.

RESULTS

Most frequently mutated genes (5% or greater) were members of the mitogen-activated protein kinase (MAPK) pathway: KRAS (23.7%, n = 36), NRAS (11.2%, n = 19), NF1 (7.9%, n = 5), and BRAF (6.6%, n = 10). Class III mutations were seen in 3 of 10 BRAF mutations while 7 were Class I V600E. Overall, estrogen and progesterone receptor expression was 80.2% (n = 130) and 27.8% (n = 45), respectively. Of those that were hormone negative, nearly 50% contained KRAS or NF1 mutations. None were NRAS mutated. Markers of response to immunotherapy were low to absent.

CONCLUSION

BRAF mutations were seen to be lower than those traditionally reported. With increased MAPK activation resulting in ligand independent activation of ERα, a role of combination therapy with hormonal and targeted therapy should be considered as 49.2% of hormone negative specimens were KRAS or NF1 mutated. Absence of immunotherapy biomarkers suggest limited benefit to immunotherapeutic agents.

Evaluation of the prognostic value of lymphadenectomy for low-grade serous ovarian cancer: A case-control multicenter retrospective study

BACKGROUND

The prognostic value of lymphadenectomy in low-grade serous ovarian cancer (LGSOC) remains uncertain.

MATERIALS AND METHODS

A retrospective analysis of 155 patients with LGSOC who underwent surgery over a ten-year period (2011-2020) was performed. The propensity score matching (PSM) algorithm was performed between the lymphadenectomy and no lymphadenectomy groups, and Kaplan-Meier analyses were conducted to evaluate clinical prognosis. Finally, univariate and multivariate Cox proportional hazards regression analyses were performed to analyze high-risk factors associated with clinical prognosis.

RESULTS

In the pre-PSM cohort, 110 (71.0%) patients underwent lymphadenectomy. Of these, 54 (34.8%) experienced recurrence, and 27 (17.4%) died. There were statistical differences in disease-free survival (DFS) (P = 0.018) and overall survival (OS) (P = 0.016) in the post-PSM cohort. In the subgroup analysis, there were no statistically significant differences in DFS (P = 0.449) or OS (P = 0.167) in the FIGO I/II cohort. However, in the FIGO III/IV cohort, DFS (P = 0.011) and OS (P = 0.046) were statistically different between the two groups. Age > 50 years, FIGO stage III/IV, and suboptimal cytoreductive surgery were risk factors associated with prognosis. In the lymphadenectomy group, the histological status of pelvic lymph nodes had no significant effect on DFS (P = 0.205) or OS (P = 0.114).

CONCLUSION

Lymphadenectomy was associated with DFS and OS, particularly in patients with advanced LGSOC patients. Age > 50 years, advanced FIGO stage III/IV, and suboptimal cytoreductive surgery were high-risk factors associated with clinical prognosis in patients with LGSOC.

CA-125 Levels Are Predictive of Survival in Low-Grade Serous Ovarian Cancer-A Multicenter Analysis

Simple Summary

Low-grade serous cancer (LGSC) accounts for approximately 5% of all ovarian cancers. It is characterized by its high resistance to chemotherapy. Cytoreductive surgery, therefore, is the primary treatment modality for this disease and previous studies have shown that complete removal of all visible tumor tissue should be achieved. In this study, 176 women with LGSC were included and most of them had advanced disease stages, where the disease had already spread. CA-125 is a biomarker that has been previously studied in ovarian cancer. We have found that CA-125 level following treatment of LGSC is an important and independent prognostic factor for progression-free and overall survival. It may be a better surrogate for the true amount of residual disease following treatment compared to the gross estimation of visible residual disease during surgery.

Abstract

Objective: Studies on low-grade serous ovarian cancer (LGSC) are limited by a low number of cases. The aim of this study was to define the prognostic significance of age, stage, and CA-125 levels on survival in a multi-institutional cohort of women with pathologically confirmed LGSC. Methods: Women with LGSC were identified from the collaborative Ovarian Cancer Association Consortium (OCAC). Cases of newly diagnosed primary LGSC were included if peri-operative CA-125 levels were available. Age at diagnosis, FIGO stage, pre- and post-treatment CA-125 levels, residual disease, adjuvant chemotherapy, disease recurrence, and vital status were collected by the participating institutions. Progression-free (PFS) and overall survival (OS) were calculated. Multivariable (MVA) Cox proportional hazard models were used and hazard ratios (HR) calculated. Results: A total of 176 women with LGSC were included in this study; 82% had stage III/IV disease. The median PFS was 2.3 years and the median OS was 6.4 years. Age at diagnosis was not significantly associated with worse PFS (p = 0.23) or OS (p = 0.3) (HR per year: 0.99; 95%CI, 0.96–1.01 and 0.98; 95%CI 0.95–1.01). FIGO stage III/IV was independently associated with PFS (HR 4.26, 95%CI 1.43–12.73) and OS (HR 1.69, 95%CI 0.56–5.05). Elevated CA-125 (≥35 U/mL) at diagnosis was not significantly associated with worse PFS (p = 0.87) or OS (p = 0.78) in MVA. Elevated CA-125 (≥35 U/mL) after completion of primary treatment was independently associated with worse PFS (HR 2.81, 95%CI 1.36–5.81) and OS (HR 6.62, 95%CI 2.45–17.92). In the MVA, residual disease was independently associated with PFS (0.022), but not OS (0.85). Conclusion: Advanced LGSC was associated with poor long-term prognosis. FIGO stage and abnormal post-treatment CA-125 level are key prognostic factors inversely associated with PFS and OS. Highlights: 1. Through a multi-center collaborative effort, data from 176 women with low-grade serous ovarian cancer were analyzed. 2. Although low-grade serous ovarian cancer is often considered indolent, the progression-free and overall survival are poor. 3. Elevated post-treatment CA-125 levels are independently associated with poor survival.

Impressive and durable clinical responses obtained with dabrafenib and trametinib in low-grade serous ovarian cancer harbouring a BRAF V600E mutation

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LGSOC is characterized scarce therapeutic options in the advanced setting.

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BRAF mutations are frequent on these types of tumours.

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Dabrafenib/trametinib yield impressive responses in patients with BRAF mutations.

Low-grade serous ovarian cancer (LGSOC) is now considered a different entity from high-grade serous ovarian cancer. The chemoresistance inherent to this type of ovarian cancer narrows the therapeutic options, especially in the recurrent setting. It is thought that the mitogen-activated protein kinase (MAPK) pathway plays a significant role in the pathogenesis of these tumours, and about 2 to 20% of LGSOC harbour a BRAF mutation. Here we present a case report of two patients with a BRAF V600E mutation that achieved sustained clinical responses with combination treatment with dabrafenib (BRAF inhibitor) and trametinib (MEK inhibitor).

Can integrative biomarker approaches improve prediction of platinum and PARP inhibitor response in ovarian cancer?

Epithelial ovarian carcinoma (EOC) encompasses distinct histological, molecular and genomic entities that determine intrinsic sensitivity to platinum-based chemotherapy. Current management of each subtype is determined by factors including tumour grade and stage, but only a small number of biomarkers can predict treatment response. The recent incorporation of PARP inhibitors into routine clinical practice has underscored the need to personalise ovarian cancer treatment based on tumour biology. In this article, we review the strengths and limitations of predictive biomarkers in current clinical practice and highlight integrative strategies that may inform the development of future personalised medicine programs and composite biomarkers.

Factors associated with the involvement of lymph nodes in low-grade serous ovarian cancer

BACKGROUND AND OBJECTIVES

Evaluating nodal metastases in low-grade serous ovarian cancer (LGSOC) patients.

METHODS

Women with LGSOC who had undergone primary cytoreductive surgery comprising systematic pelvic-paraaortic lymphadenectomy were included. Data were obtained retrospectively from 12 oncology centers.

RESULTS

One hundred and forty-eight women with LGSOC who had undergone comprehensive surgical staging were included. Seventy-one (48.0%) patients had metastatic lymph nodes. Preoperative serum CA-125 levels of ≥170 U/ml (odds ratio [OR]: 3.84; 95% confidence interval [CI]: 1.22-12.07; p = 0.021) and presence of lymphovascular space invasion (LVSI) (OR: 13.72; 95% CI: 3.36-55.93; p < 0.001) were independent predictors of nodal metastasis in LGSOC. Sixty (40.5%) patients were classified to have apparently limited disease to the ovary/ovaries. Twenty (33.3%) of them were upstaged after surgical staging. Twelve (20.0%) had metastatic lymph nodes. Presence of LVSI (OR: 12.96; 95% CI: 1.14-146.43; p = 0.038) and preoperative serum CA-125 of ≥180 U/ml (OR: 7.19; 95% CI: 1.35-38.12; p = 0.02) were independent predictors of lymph node metastases in apparent Stage Ⅰ disease.

CONCLUSIONS

Clinicians may consider to perform a reoperation comprising systematic lymphadenectomy in patients who had apparently limited disease to the ovary/ovaries and had not undergone lymphadenectomy initially. Reoperation may be considered particularly in patients whose preoperative serum CA-125 is ≥180 U/ml and/or whose pathological assessment reported the presence of LVSI.

Development and Validation of Prognostic Nomogram for Primary Peritoneal Serous Carcinoma Compared With FIGO Staging System: A Population-Based Study

Background

Primary peritoneal serous carcinoma (PPSC) is a rare tumor that lacks a prognostic prediction model. Our study aims to develop a nomogram to predict overall survival (OS) of PPSC patients.

Methods

Patients confirmed to have PPSC between 2004 and 2012 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. LASSO and multivariate Cox regression analyses were used to screen for meaningful independent prognostic factors to construct a nomogram model for 3-, 5-, and 10-year OS among patients with PPSC. The nomogram compared the discrimination, calibration, and net benefits with the International Federation of Gynecology and Obstetrics (FIGO) staging system of PPSC patients.

Results

Eight variables were selected to establish the nomogram for PPSC. The established nomogram performed significantly better than the FIGO staging system (p < 0.05). The 3-, 5-, and 10-year OS of PPSC was 0.498, 0.306, and 0.152, respectively. Patients of old age, widowed marital status, grade high, FIGO IIIB, IIIC, or IV, lymph node metastasis, no lymphadenectomy, no surgery, and no chemotherapy got higher score which corresponds with higher risk and lower OS. In the multivariate Cox regression analysis, age, histological grade, FIGO staging, lymph node metastasis, and lymphadenectomy (four or more) were identified as independent prognostic factors for PPSC.

Conclusions

PPSC patients have distinct characteristics with respect to their presentation and survival outcomes. A prognostic nomogram constructed by various clinical indicators can provide better and more accurate predictions for patients with PPSC.

Impact of cytoreductive surgery on survival of patients with low-grade serous ovarian carcinoma: A multicentric study of Turkish Society of Gynecologic Oncology (TRSGO-OvCa-001)

BACKGROUND AND OBJECTIVES

The aim of this study was to analyze the factors affecting recurrence-free (RFS) and overall survival (OS) rates of women diagnosed with low-grade serous ovarian cancer (LGSOC).

METHODS

Databases from 13 participating centers in Turkey were searched retrospectively for women who had been treated for stage I-IV LGSOC between 1997 and 2018.

RESULTS

Overall 191 eligible women were included. The median age at diagnosis was 49 years (range, 21-84 years). One hundred seventy-five (92%) patients underwent primary cytoreductive surgery. Complete and optimal cytoreduction was achieved in 148 (77.5%) and 33 (17.3%) patients, respectively. The median follow-up period was 44 months (range, 2-208 months). Multivariate analysis showed the presence of endometriosis (p = .012), lymphovascular space invasion (LVSI) (p = .022), any residual disease (p = .023), and the International Federation of Gynecology and Obstetrics (FIGO) stage II-IV disease (p = .045) were negatively correlated with RFS while the only presence of residual disease (p = .002) and FIGO stage II-IV disease (p = .003) significantly decreased OS.

CONCLUSIONS

The maximal surgical effort is warranted for complete cytoreduction as achieving no residual disease is the single most important variable affecting the survival of patients with LGSOC. The prognostic role of LVSI and endometriosis should be evaluated by further studies as both of these parameters significantly affected RFS.

Differences between primary peritoneal serous carcinoma and advanced serous ovarian carcinoma: a study based on the SEER database

Objective

This study aimed to compare clinical features and overall survival (OS) between patients with primary peritoneal serous carcinoma (PPSC) and those with advanced serous ovarian carcinoma (ASOC) and to identify prognostic factors.

Methods

Patients diagnosed with PPSC and ASOC from 2010 to 2015 from the Surveillance, Epidemiology, and End Results (SEER) database were enrolled. Pearson’s chi-square test was used to compare clinical features. The primary endpoint was OS. The Kaplan–Meier method and log–rank test were used to perform the survival analysis. Propensity score matching was also conducted. Univariate, multivariate and subgroup analyses were performed using the Cox proportional hazards model.

Results

A total of 708 PPSC patients and 7610 ASOC patients were enrolled. The clinical features of PPSC patients were noticeably different from those of ASOC patients. The survival analysis showed that PPSC patients had poorer outcomes than ASOC patients. Even after the clinical features were balanced, PPSC patients still had poorer survival. Univariate and multivariate analyses indicated that older age, higher tumor grade and advanced American Joint Committee on Cancer stage were adverse prognostic factors in both groups, while surgery and chemotherapy were protective factors. A subgroup analysis demonstrated that most factors favored ASOC patients. The total distant metastasis rates of PPSC and ASOC were similar. Liver or lung metastasis was common, but bone and brain metastases were rare. A higher proportion of liver metastasis was observed in the ASOC group.

Conclusion

The clinical features and survival outcomes between PPSC patients and ASOC patients are clearly different, and PPSC is more aggressive than ASOC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-021-00788-y.

KRAS-Mutated, Estrogen Receptor-Positive Low-Grade Serous Ovarian Cancer: Unraveling an Exceptional Response Mystery

We report on a woman with aggressive estrogen receptor‐positive, KRAS‐mutated ovarian cancer who achieved a remarkable response to combination therapy with the MEK inhibitor (trametinib) and the aromatase inhibitor (letrozole), even though the disease had failed to respond to a combination of a PI3K inhibitor and different MEK inhibitor, as well as to trametinib and the estrogen modulator, tamoxifen, and to letrozole by itself. The mechanism of action for exceptional response was elucidated by in vitro experiments that demonstrated that the fact that tamoxifen can have an agonistic effect in addition to antagonist activity, whereas letrozole results only in estrogen depletion was crucial to the response achieved when letrozole was combined with an MEK inhibitor. Our current observations indicate that subtle variations in mechanisms of action of outwardly similar regimens may have a major impact on outcome and that such translational knowledge is critical for optimizing a precision medicine strategy.

Key Points

This report describes the remarkable response of a patient with KRAS‐mutated, estrogen receptor‐positive low‐grade serous ovarian cancer treated with trametinib (MEK inhibitor) and letrozole (aromatase inhibitor), despite prior progression on similar agents including tamoxifen (estrogen modulator).

In vitro investigation revealed that tamoxifen can have agonistic in addition to antagonistic effects, which could be the reason for the patient not responding to the combination of trametinib and tamoxifen.

The current observations suggest that drugs with different mechanisms of action targeting the same receptor may have markedly different anticancer activity when used in combinations.

This article reports the case of a patient with aggressive estrogen receptor‐positive, KRAS‐mutated ovarian cancer who achieved a remarkable response to combination therapy with the MEK inhibitor trametinib and the aromatase inhibitor letrozole, despite earlier failures of treatment with other combination inhibitor treatment. This article focuses on the possibility that subtle variations in mechanisms of action of outwardly similar regimens may have major effects on patient outcomes.

Multiomics Characterization of Low-Grade Serous Ovarian Carcinoma Identifies Potential Biomarkers of MEK Inhibitor Sensitivity and Therapeutic Vulnerability

Low-grade serous ovarian carcinoma (LGSOC) is a rare tumor subtype with high case fatality rates in patients with metastatic disease. There is a pressing need to develop effective treatments using newly available preclinical models for therapeutic discovery and drug evaluation. Here, we use multiomics integration of whole-exome sequencing, RNA sequencing, and mass spectrometry-based proteomics on 14 LGSOC cell lines to elucidate novel biomarkers and therapeutic vulnerabilities. Comparison of LGSOC cell line data with LGSOC tumor data enabled predictive biomarker identification of MEK inhibitor (MEKi) efficacy, with KRAS mutations found exclusively in MEKi-sensitive cell lines and NRAS mutations found mostly in MEKi-resistant cell lines. Distinct patterns of Catalogue of Somatic Mutations in Cancer mutational signatures were identified in MEKi-sensitive and MEKi-resistant cell lines. Deletions of CDKN2A/B and MTAP genes were more frequent in cell lines than tumor samples and possibly represent key driver events in the absence of KRAS/NRAS/BRAF mutations. These LGSOC cell lines were representative models of the molecular aberrations found in LGSOC tumors. For prediction of in vitro MEKi efficacy, proteomic data provided better discrimination than gene expression data. Condensin, minichromosome maintenance, and replication factor C protein complexes were identified as potential treatment targets in MEKi-resistant cell lines. This study suggests that CDKN2A/B or MTAP deficiency may be exploited using synthetically lethal treatment strategies, highlighting the importance of using proteomic data as a tool for molecular drug prediction. Multiomics approaches are crucial to improving our understanding of the molecular underpinnings of LGSOC and applying this information to develop new therapies. SIGNIFICANCE: These findings highlight the utility of global multiomics to characterize LGSOC cell lines as research models, to determine biomarkers of MEKi resistance, and to identify potential novel therapeutic targets.

Clinical factors associated with prognosis in low-grade serous ovarian carcinoma: experiences at two large academic institutions in Korea and Taiwan

Low-grade ovarian serous carcinoma (LGSOC) has clinical features different from high-grade serous ovarian carcinoma (HGSOC) accounting for the majority of epithelial ovarian cancer. Because of its rarity, previous studies have only focused on the high-grade disease without considering the differences between the two subtypes. This study aimed to evaluate the effect of the clinical prognostic factors known for HGSOC on survival in patients with LGSOC. Based on the Federation of Gynecology and Obstetrics (FIGO) stage, progression-free survival (PFS) was markedly decreased in advanced disease compared with early disease. For stage I, patients with stage IC had poorer survival than those with stage IA and IB regardless of the number of cycles of adjuvant chemotherapy. For advanced disease, no gross residual disease after primary cytoreductive surgery was significantly associated with longer PFS when compared with gross residual disease. In multivariate analysis for PFS and overall survival (OS), age, preoperative CA-125, time interval from surgery to chemotherapy, and the number of cycles of adjuvant chemotherapy were not associated with prognosis. Complete cytoreduction was the only independent prognostic factor for PFS (HR 2.45, p = 0.045). Our study revealed that the known prognostic factors in HGSOC did not show any effect on the survival in LGSOC except for FIGO stage and complete cytoreduction.

Glucocorticoids induce differentiation and chemoresistance in ovarian cancer by promoting ROR1-mediated stemness

Glucocorticoids are routinely used in the clinic as anti-inflammatory and immunosuppressive agents as well as adjuvants during cancer treatment to mitigate the undesirable side effects of chemotherapy. However, recent studies have indicated that glucocorticoids may negatively impact the efficacy of chemotherapy by promoting tumor cell survival, heterogeneity, and metastasis. Here, we show that dexamethasone induces upregulation of ROR1 expression in ovarian cancer (OC), including platinum-resistant OC. Increased ROR1 expression resulted in elevated RhoA, YAP/TAZ, and BMI-1 levels in a panel of OC cell lines as well as primary ovarian cancer patient-derived cells, underlining the translational relevance of our studies. Importantly, dexamethasone induced differentiation of OC patient-derived cells ex vivo according to their molecular subtype and the phenotypic expression of cell differentiation markers. High-throughput drug testing with 528 emerging and clinical oncology compounds of OC cell lines and patient-derived cells revealed that dexamethasone treatment increased the sensitivity to several AKT/PI3K targeted kinase inhibitors, while significantly decreasing the efficacy of chemotherapeutics such as taxanes, as well as anti-apoptotic compounds such as SMAC mimetics. On the other hand, targeting ROR1 expression increased the efficacy of taxane drugs and SMAC mimetics, suggesting new combinatorial targeted treatments for patients with OC.

Therapeutic Approach to Low-Grade Serous Ovarian Carcinoma: State of Art and Perspectives of Clinical Research

Low-grade serous ovarian carcinoma (LGSOC) is a distinct pathologic and clinical entity, characterized by less aggressive biological behavior, lower sensitivity to chemotherapy and longer survival compared with high-grade serous ovarian carcinoma. LGSOC often harbors activating mutations of genes involved in mitogen activated protein kinase (MAPK) pathway. Patients with disease confined to the gonad(s) should undergo bilateral salpingo-oophorectomy, total hysterectomy and comprehensive surgical staging, although fertility-sparing surgery can be considered in selected cases. Women with stage IA-IB disease should undergo observation alone after surgery, whereas observation, chemotherapy or endocrine therapy are all possible options for those with stage IC-IIA disease. Patients with advanced disease should undergo primary debulking surgery with the aim of removing all macroscopically detectable disease, whereas neoadjuvant chemotherapy followed by interval debuking surgery. After surgery, the patients can receive either carboplatin plus paclitaxel followed by endocrine therapy or endocrine therapy alone. Molecularly targeted agents, and especially MEK inhibitors and Cyclin-dependent kinase (CDK) inhibitors, are currently under evaluation. Additional research on the genomics of LGSOC and clinical trials on the combination of MEK inhibitors with hormonal agents, other molecularly targeted agents or metformin, are strongly warranted to improve the prognosis of patients with this malignancy.

Evolving population-based statistics for rare epithelial ovarian cancers

OBJECTIVE

To describe how population-based statistics for rare epithelial ovarian cancers are evolving.

METHODS

This is a retrospective observational study examining the Surveillance, Epidemiology, and End Results Program from 1988 to 2016. Overall survival (OS) of clear cell (OCCC), mucinous (MOC), and low-grade serous (LGSOC) ovarian cancers were compared to high-grade serous ovarian cancer (HGSOC) by fitting a propensity score matching.

RESULTS

Among 113,365 ovarian malignancies, 5780 OCCCs (5.1%), 7561 MOCs (6.7%), and 2021 LGSOCs (1.8%) were compared to 38,199 HGSOCs. OCCCs and MOCs were more likely to be diagnosed with stage I disease compared to HGSOC (57.0-59.5% versus 8.6%, P<0.001). For early-stage disease, OCCC (hazard ratio [HR] 0.91, 95% confidence interval [CI] 0.82-1.01) and MOC (HR 0.94, 95%CI 0.85-1.04) had similar OS to HGSOC whereas LGSOC had superior OS (HR 0.93, 95%CI 0.89-0.97) versus HGSOC. Conversely, for advanced-stage disease, OCCC (HR 1.42, 95%CI 1.32-1.53) and MOC (HR 1.11, 95%CI 1.09-1.13) had poorer OS whereas LGSOC (HR 0.86, 95%CI 0.84-0.89) had superior OS compared to HGSOC. OCCC (HR range, 1.92-2.45) and MOC (HR range, 1.73-2.22) had particularly poorer OS in the first three years following diagnosis compared to HGSOC. Population-level statistics for advanced-stage disease showed that 5-year OS rates have increased in HGSOC (16.9% to 36.8%, P<0.001) and LGSOC (50.8% to 66.4%, P=0.010); but remain unchanged for OCCC (21.0% to 28.2%, P=0.174) and MOC (21.4% to 16.5%, P=0.102).

CONCLUSION

OCCC, MOC, and LGSOC comprise 2-7% of ovarian malignancies, have distinct characteristics and survival compared to HGSOC. While these rare tumors have a favorable to comparable prognosis in early-stage disease, disproportionally poor survival in advanced-stage OCCC and MOC highlights the need for further research into novel treatment strategies.

Diagnosis-shift between low-grade serous ovarian cancer and serous borderline ovarian tumor: A population-based study

OBJECTIVE

To determine changes in the characteristics of low-grade serous ovarian cancer (LGSOC) and serous borderline ovarian tumor (serous-BOT) in a time-specific manner.

METHODS

We conducted a population-based retrospective study examining the Surveillance, Epidemiology, and End Results Program from 1988 to 2000. Trends, demographics, and outcomes of 775 women with well-differentiated serous ovarian cancer, used as a surrogate for LGSOC, were compared to 3937 women with serous-BOT.

RESULTS

In the multivariable analysis, women with LGSOC were more likely to be older, have stage II-IV disease, and have undergone hysterectomy at surgery, but less likely to be a Western U.S. resident compared to those with serous-BOT (all, adjusted-P < 0.05). During the study period, the number of LGSOCs decreased by 25.9%, particularly stage I disease (37.6% relative decrease) compared to stage II-IV disease (21.1% relative decrease) (all, P < 0.05). With a median follow-up of 16.9 years, there was a decreasing trend in the 15-year overall survival rates among LGSOC (28.7% relative decrease, P = 0.056) but not in serous-BOT (2.5% relative increase, P = 0.416) as a whole cohort. The magnitude of hazard risk from all-cause death for women with LGSOC compared to those with serous-BOT increased by 68.9% from 1988 to 2000 (P < 0.001). LGSOC remained an independent prognostic factor for decreased overall survival compared to serous-BOT (adjusted-P < 0.05).

CONCLUSION

Our study suggests that the decreasing number and survival of LGSOC over time may be due to a diagnosis-shift from LGSOC to serous-BOT. Given the distinct characteristics and outcomes of LGSOC compared to serous-BOT, our study endorses the importance of making the correct diagnosis upfront. Whether this diagnostic-shift supports a hypothesis that serous-BOT is a precursor lesion of LGSOC merits further investigation.

Hormone receptor expression and outcomes in low-grade serous ovarian carcinoma

OBJECTIVE

Low-grade serous ovarian carcinomas (LGSC) are frequently ER/PR positive, though the mechanisms by which ER/PR regulate prognosis or anti-estrogen treatment efficacy are poorly understood. We studied ER/PR expression in LGSC tumors and cell lines to evaluate patient outcomes and cellular treatment responses.

METHODS

LGSC tumors and patient-derived cell lines were studied from patients with advanced-stage (III/IV) disease. Tumor samples and clinical data were obtained from the Canadian Ovarian Experimental Unified Resource (COEUR-tissue microarray) and the Ovarian Cancer Research (OvCaRe) tissue bank. ER/PR expression was assessed by both Western blot and immunohistochemistry (IHC). Two different IHC scoring systems (simple and Allred) were used. Cox regression was used to identify factors (age, disease residuum, ER/PR status, etc.) associated with progression-free (PFS) and overall survival (OS). Estradiol and tamoxifen proliferation and viability experiments were performed in LGSC cell lines.

RESULTS

In 55 LGSC cases studied, median follow-up was 56 months (range 1-227). Fifty-three (96%) cases strongly expressed ER whereas 37 (67%) expressed PR. Cox-regression analysis showed that residuum (p < 0.001) was significantly associated with PFS, whereas both ER Allred score (p = 0.005) and residuum (p = 0.004) were significant for OS. None of the LGSC cell lines expressed PR. Loss of PR and ER expression over time was detected in LGSC tumors and cell lines respectively. Estrogen and tamoxifen treatment did not alter LGSC cell proliferation or viability in-vitro.

CONCLUSIONS

In patients with advanced LGSC, higher ER Allred scores were significantly associated with better overall survival. ER/PR expression changed over time in both LGSC tumors and cell lines. Better translational research models are needed to elucidate the molecular mechanisms of ER/PR signalling in LGSC.

The miR-34 family and its clinical significance in ovarian cancer

The tumor suppressor miR-34 family is transcriptionally induced by p53. Clinical significance of the various miR-34 family members has not been studied in ovarian cancer. In 228 ovarian cancers and in 19 non-neoplastic fallopian tube samples we analysed miR-34 a/b/c expression in relation to clinicopathological characteristics and clinical outcome. We found significantly lower levels of miR-34 a/b/c in ovarian cancers as compared to control-tissues (P=0.002, P<0.001, P<0.001, respectively). Expression of miR-34 b/c revealed an inverse correlation with BRCA1/2 mRNA-expression (BRCA1: miR34 b/c P=0.002 each; BRCA2: miR-34 b/c P<0.001 each), the same was true for miR-34a and BRCA2 mRNA-expression (P<0.001). The miR-34 family expression was found to be significantly lower in type 2 in comparison to type 1 cancers (P<0.001) and in TP53-mutated compared with TP53-wild-type ovarian cancers (P<0.001, P=0.002, P=0.004, respectively). When low grade serous ovarian cancers were compared with high grade serous cancers the respective miR-34 a/b/c expression was 2.6-, 40.8- and 32.3-fold higher. The expression of each of the miR-34 family members was revealed to be of independent prognostic relevance regarding progression free survival (PFS); miR-34a: HR 0.6, P=0.033; miR-34b: HR 0.2, P=0.001 and miR-34c: HR 0.3, P=0.002, respectively). For overall survival (OS) independency of the prognostic value was confined to miR-34b (HR 0.4, P=0.016) and miR-34c (HR 0.6, P=0.049). The independency of the prognostic value of our identified thresholds was confirmed for PFS for miR-34c in a publicly available dataset (NCBI Gene Expression Omnibus GSE73582). Our findings suggest that downregulation of miR-34 family is a crucial part in ovarian cancer development. Low miR-34 levels are linked to a worse overall survival and progression free survival and may indicate a more aggressive disease.

Low-grade serous ovarian carcinoma: A comprehensive literature review

BACKGROUND

Low-grade serous ovarian carcinoma (LGSOC) is a unique entity with clinical and molecular characteristics distinct from high-grade serous ovarian carcinoma (HGSOC). To date the majority of research has focused on the more common HGSOC, with treatment recommendations often extrapolated to LGSOC. Women with LGSOC are typically diagnosed younger and have indolent and relatively chemoresistant disease. Recently there have been major research advances in LGSOC.

AIMS

This systematic review describes the epidemiological, clinical and molecular characteristics of LGSOC, with advances in research and novel treatment options also discussed.

MATERIALS AND METHODS

A 10-year comprehensive systematic review of peer-reviewed literature was conducted, with a total of 132 abstracts read, 89 articles reviewed and 49 included in this review.

RESULTS

This review highlights the clinical and molecular features of LGSOC, current and traditional treatment options and areas of current research into targeted agents.

CONCLUSIONS

Our growing knowledge about LGSOC as a distinct clinical and molecular entity from HGSOC has led to the investigation of more targeted and tailored therapies as their clinical course, optimal management and therapeutic targets differ. There is a need for ongoing collaborative research to provide better treatment options for these patients.

Asparagine Synthetase and Filamin A Have Different Roles in Ovarian Cancer

Early-stage ovarian serous carcinoma is usually difficult to detect in clinical practice. The profiling of protein expression in high-grade serous carcinoma (HGSC) and low-grade serous carcinoma (LGSC) would provide important information for diagnoses and chemotherapy. Here, we performed proteomic profiling of specimens from 13 HGSC and 7 LGSC patients by iTRAQ. A total of 323 proteins that were differentially expressed were identified. After immunohistochemical confirmation of expressed proteins in 166 clinical tissues, asparagine synthetase (ASNS) and filamin A (FLNA) were selected for further functional study. Cisplatin-sensitive (CS; ASNS^high and FLNA^low) and cisplatin-resistant (CR; ASNS^low and FLNA^high) SKOV3 and OVCAR3 ovarian cancer cell lines were used for subsequent in vitro and in vivo experiments. Notably, ASNS overexpression (ASNS⁺) or FLNA knockdown (shFLNA) enabled cisplatin-induced apoptosis and autophagy in CR cells. However, ASNS⁺ and shFLNA promoted and attenuated tumor growth, respectively. In CS cells, ASNS knockdown (shASNS) attenuated clonogenicity, cell proliferation, and the epithelial–mesenchymal transition, whereas FLNA overexpression (FLNA⁺) protected cells from cisplatin. In vivo, cisplatin resistance was attenuated in mice xenografted with ASNS⁺, shFLNA, or ASNS⁺-shFLNA CR cells, whereas xenografts of shASNS or FLNA⁺ CS cells exhibited resistance to cisplatin. Clinically, all HGSC patients (83/83) responded to cisplatin, while 6 in 41 LGSC patients exhibited cisplatin resistance. These findings identify ASNS and FLNA as distinct biomarkers for HGSC and LGSC, which may have potential value in the prognosis and clinical treatment of serous carcinoma.

Cutaneous Metastases in Ovarian Cancer

Skin metastases in ovarian cancer are uncommon, but their incidence may be increasing due to improved survival rates. Skin metastases can be divided into umbilical metastases, which are known as Sister Joseph nodules (SJNs) and are associated with peritoneal metastasis, and non-SJN skin metastases, which usually develop within surgical scars and in the vicinity of superficial lymphadenopathy. As most skin metastases develop after specific conditions, recognition of preceding metastatic diseases and prior treatments is necessary for early diagnosis of skin lesions. The prognosis of skin metastases in ovarian cancer varies widely since they are heterogeneous in the site of lesion and the time of appearance. Patients with SJNs at initial diagnosis and patients with surgical scar recurrences without concomitant metastases may have prolonged survival with a combination of surgery and chemotherapy. In patients who developed skin recurrences as a late manifestation, symptoms should be treated with external beam radiotherapy and immune response modifiers. Immune checkpoint blockade can enhance anti-tumor immunity and induce durable clinical responses in multiple tumor types, including advanced chemoresistant ovarian cancer. With the use of radiation therapy, which enhances the systemic anti-tumor immune response, immune checkpoint blockade may be a promising therapeutic strategy for distant metastasis, including skin metastasis.

Low Grade Ovarian Serous Carcinoma - A Clinical-Morphologic Study

Low grade ovarian serous carcinomas (LGSC) are rare tumors, representing only a small part of all ovarian carcinomas. The study included six LGSC cases for which we followed the clinical-epidemiological and morphological parameters depending on the tumoral stages. The tumors corresponded to stage I in four cases, in one case to stage II and in another case to stage III. The majority of the analyzed histopathological parameters were present in all tumoral stages. The accuracy of the diagnostic and the correct staging of the LGSC affected patients is very important, because the grade and stage of the serous ovarian tumors impose the therapy and the prognosis.

Relevance of minor discrepancies at second pathology review in gynaecological cancer

Aim

To determine the incidence of discrepancy rate between the initial pathology diagnosis and referral diagnosis in women with gynaecological cancer.

Methods

A retrospective observational study was performed including all consecutive patients with gynaecological cancer referred and who underwent pathologic review between January 2013 and May 2017. Discrepancies were minor when future treatment was not altered or major when the treatment was modified.

Results

A total of 259 patients were included. The original diagnosis was ovarian cancer (n = 126, 48.6%), endometrial cancer (n = 84, 32.4%), cervical cancer (n = 43, 16.6%) and vulvar cancer (n = 6, 2.3%). Eighteen women (6.9%) had major discrepancies and 69 patients (26.6%) had minor discrepancies. The main reason for the minor discrepancy was tumour grade or histology subtype. Regarding ovarian cancer, 13 out of 16 patients had minor discrepancies at histology subtype among serous, endometrioid, mucinous or undifferentiated tumours. The main issue for the minor discrepancy in patients with cervical cancer was among different subtype of cervical adenocarcinoma. Minor discrepancies due to tumour grade were also observed in 14, 19, 8 and 3 patients with endometrial, ovarian, cervical and vulvar cancer, respectively.

Conclusions

A second pathology review also adds valid information in those cases with minor discrepancies leading to a difference in patients´ counselling regarding follow-up and prognosis.

Frontiers in the Pathology and Pathogenesis of Ovarian Cancer: Cancer Precursors and "Precursor Escape"

This article summarizes the pathogenesis of ovarian carcinoma, focusing on the paradox of high-grade serous carcinogenesis. The fallopian tube is the prime site of origin in early serous cancers. Because a subset of serous cancers is associated with early serous proliferations absent intramucosal carcinomas, "precursor escape" is emerging, whereby some advanced cancers trace their roots to early serous proliferations. This has parallels in the endometriosis model and opens up a novel mechanism by which advanced malignancy could emerge without an obvious tubal carcinoma. The impact of this concept on classification of serous cancer and expectations from preventive strategies are discussed.

Markers of MEK inhibitor resistance in low-grade serous ovarian cancer: EGFR is a potential therapeutic target

BACKGROUND

Although low-grade serous ovarian cancer (LGSC) is rare, case-fatality rates are high as most patients present with advanced disease and current cytotoxic therapies are not overly effective. Recognizing that these cancers may be driven by MAPK pathway activation, MEK inhibitors (MEKi) are being tested in clinical trials. LGSC respond to MEKi only in a subgroup of patients, so predictive biomarkers and better therapies will be needed.

METHODS

We evaluated a number of patient-derived LGSC cell lines, previously classified according to their MEKi sensitivity. Two cell lines were genomically compared against their matching tumors samples. MEKi-sensitive and MEKi-resistant lines were compared using whole exome sequencing and reverse phase protein array. Two treatment combinations targeting MEKi resistance markers were also evaluated using cell proliferation, cell viability, cell signaling, and drug synergism assays.

RESULTS

Low-grade serous ovarian cancer cell lines recapitulated the genomic aberrations from their matching tumor samples. We identified three potential predictive biomarkers that distinguish MEKi sensitive and resistant lines: KRAS mutation status, and EGFR and PKC-alpha protein expression. The biomarkers were validated in three newly developed LGSC cell lines. Sub-lethal combination of MEK and EGFR inhibition showed drug synergy and caused complete cell death in two of four MEKi-resistant cell lines tested.

CONCLUSIONS

KRAS mutations and the protein expression of EGFR and PKC-alpha should be evaluated as predictive biomarkers in patients with LGSC treated with MEKi. Combination therapy using a MEKi with EGFR inhibition may represent a promising new therapy for patients with MEKi-resistant LGSC.

Markers of MEK inhibitor resistance in low-grade serous ovarian cancer: EGFR is a potential therapeutic target

Background

Although low-grade serous ovarian cancer (LGSC) is rare, case-fatality rates are high as most patients present with advanced disease and current cytotoxic therapies are not overly effective. Recognizing that these cancers may be driven by MAPK pathway activation, MEK inhibitors (MEKi) are being tested in clinical trials. LGSC respond to MEKi only in a subgroup of patients, so predictive biomarkers and better therapies will be needed.

Methods

We evaluated a number of patient-derived LGSC cell lines, previously classified according to their MEKi sensitivity. Two cell lines were genomically compared against their matching tumors samples. MEKi-sensitive and MEKi-resistant lines were compared using whole exome sequencing and reverse phase protein array. Two treatment combinations targeting MEKi resistance markers were also evaluated using cell proliferation, cell viability, cell signaling, and drug synergism assays.

Results

Low-grade serous ovarian cancer cell lines recapitulated the genomic aberrations from their matching tumor samples. We identified three potential predictive biomarkers that distinguish MEKi sensitive and resistant lines: KRAS mutation status, and EGFR and PKC-alpha protein expression. The biomarkers were validated in three newly developed LGSC cell lines. Sub-lethal combination of MEK and EGFR inhibition showed drug synergy and caused complete cell death in two of four MEKi-resistant cell lines tested.

Conclusions

KRAS mutations and the protein expression of EGFR and PKC-alpha should be evaluated as predictive biomarkers in patients with LGSC treated with MEKi. Combination therapy using a MEKi with EGFR inhibition may represent a promising new therapy for patients with MEKi-resistant LGSC.

Markers of MEK inhibitor resistance in low-grade serous ovarian cancer: EGFR is a potential therapeutic target

Background

Although low-grade serous ovarian cancer (LGSC) is rare, case-fatality rates are high as most patients present with advanced disease and current cytotoxic therapies are not overly effective. Recognizing that these cancers may be driven by MAPK pathway activation, MEK inhibitors (MEKi) are being tested in clinical trials. LGSC respond to MEKi only in a subgroup of patients, so predictive biomarkers and better therapies will be needed.

Methods

We evaluated a number of patient-derived LGSC cell lines, previously classified according to their MEKi sensitivity. Two cell lines were genomically compared against their matching tumors samples. MEKi-sensitive and MEKi-resistant lines were compared using whole exome sequencing and reverse phase protein array. Two treatment combinations targeting MEKi resistance markers were also evaluated using cell proliferation, cell viability, cell signaling, and drug synergism assays.

Results

Low-grade serous ovarian cancer cell lines recapitulated the genomic aberrations from their matching tumor samples. We identified three potential predictive biomarkers that distinguish MEKi sensitive and resistant lines: KRAS mutation status, and EGFR and PKC-alpha protein expression. The biomarkers were validated in three newly developed LGSC cell lines. Sub-lethal combination of MEK and EGFR inhibition showed drug synergy and caused complete cell death in two of four MEKi-resistant cell lines tested.

Conclusions

KRAS mutations and the protein expression of EGFR and PKC-alpha should be evaluated as predictive biomarkers in patients with LGSC treated with MEKi. Combination therapy using a MEKi with EGFR inhibition may represent a promising new therapy for patients with MEKi-resistant LGSC.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0725-1) contains supplementary material, which is available to authorized users.

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.

Missing information in statewide and national cancer databases: Correlation with health risk factors, geographic disparities, and outcomes

OBJECTIVE

The objectives of this study were to analyze factors associated with outcomes and missing data in women with epithelial ovarian cancer using institutional, state and national databases.

METHODS

Data were abstracted from the University of Virginia cancer registry, Virginia Department of Health (VDH) database, and Surveillance, Epidemiology, and End Results (SEER) Program and analyzed for correlations with demographics, cancer characteristics, and outcomes. Statewide spatial associations between health risk factors such as smoking, obesity, and missing grade/stage were evaluated using bivariate LiSA in Geoda.

RESULTS

There were 524 institutional, 3544 VDH, and 44,464 SEER cases of epithelial ovarian cancer. Institutional cases were younger, most often of white race, had increased grade 1, and decreased unknown grade and stage (all p < 0.001). Significant predictors of unknown grade were non-white race, older age, no surgery, unknown stage/stage IV, and unknown histology/adenocarcinoma. Unknown grade correlated with a significant survival disadvantage. Missing stage and grade correlated with county-level obesity and smoking, as rural regions in Southwest and Southside Virginia had high rates of health risk factors and missing stage/grade compared to urban, affluent regions in Northern Virginia.

CONCLUSIONS

Over a third of nationally reported cases have an unknown grade and 10-20% have an unknown stage which correlates with the worst survival. Predictors of unknown grade include insurance, age, race, smoking status, obesity, and rural setting. Missing data may represent geographical differences or disparities in cancer care available as significantly fewer cases had an unknown grade/stage at a tertiary academic medical center compared to VDH and SEER.

Low-grade Serous Ovarian Carcinoma

In the early 2000s a two-tier grading system was introduced for serous ovarian cancer. Since then, we have increasingly come to accept that low-grade serous ovarian carcinoma (LGSOC) is a separate entity with a unique mutational landscape and clinical behaviour. As less than 10% of serous carcinomas of the ovary are low-grade, they are present in only a small number of patients in clinical trials for ovarian cancer. Therefore the current treatment of LGSOC is based on smaller trials, retrospective series, and subgroup analysis of large clinical trials on ovarian cancer. Surgery plays a major role in the treatment of patients with LGSOC. In the systemic treatment of LGSOC, hormonal treatment and targeted therapies seem to play an important role.

The detrimental effect of adopting interval debulking surgery in advanced stage low-grade serous ovarian cancer

OBJECTIVE

To examine outcomes of patients having treatments for newly diagnosed advanced stage low-grade serous ovarian cancer (LGSC).

METHODS

We conducted a retrospective case series of women affected by advanced stage (stage IIIB or more) LGSC undergoing surgery in a single oncologic center between January 2000 and December 2017. Survival outcomes were assessed using Kaplan-Meier and Cox models.

RESULTS

Data of 72 patients were retrieved. Primary cytoreductive surgery was attempted in 68 (94.4%) patients: 19 (27.9%) had residual disease (RD) >1 cm after primary surgery. Interval debulking surgery (IDS) was attempted in 15 of these 19 (78.9%) patients and the remaining 4 patients having not primary debulking surgery. Twelve out of 19 (63.1%) patients having IDS had RD. After a mean (±standard deviation) follow-up was 61.6 (±37.2) months, 50 (69.4%) and 22 (30.5%) patients recurred and died of disease, respectively. Via multivariate analysis, non-optimal cytoreduction (hazard ratio [HR]=2.79; 95% confidence interval [CI]=1.16-6.70; p=0.021) and International Federation of Obstetrics and Gynecologists (FIGO) stage IV (HR=3.15; 95% CI=1.29-7.66; p=0.011) were associated with worse disease-free survival. Via multivariate analysis, absence of significant comorbidities (HR=0.56; 95% CI=0.29-1.10; p=0.093) and primary instead of IDS (HR=2.95; 95% CI=1.12-7.74; p=0.027) were independently associated with an improved overall survival.

CONCLUSION

LGSC is at high risk of early recurrence. However, owing to the indolent nature of the disease, the majority of patients are long-term survivors. Further prospective studies and innovative treatment modalities are warranted to improve patients care.