High throughput screening identifies dasatinib as synergistic with trametinib in low grade serous ovarian carcinoma.

BACKGROUND: Low grade serous ovarian carcinoma (LGSOC) is a distinct histotype of ovarian cancer characterised high levels of intrinsic chemoresistance, highlighting the urgent need for new treatments. High throughput screening in clinically-informative cell-based models represents an attractive strategy for identifying candidate treatment options for prioritisation in clinical studies. METHODS: We performed a high throughput drug screen of 1610 agents across a panel of 6 LGSOC cell lines (3 RAS/RAF-mutant, 3 RAS/RAF-wildtype) to identify novel candidate therapeutic approaches. Validation comprised dose-response analysis across 9 LGSOC models and 5 high grade serous comparator lines. RESULTS: 16 hits of 1610 screened compounds were prioritised for validation based on >50% reduction in nuclei counts in over half of screened cell lines at 1000 nM concentration. 11 compounds passed validation, and the four agents of greatest interest (dasatinib, tyrosine kinase inhibitor; disulfiram, aldehyde dehydrogenase inhibitor; carfilzomib, proteasome inhibitor; romidepsin, histone deacetylase inhibitor) underwent synergy profiling with the recently approved MEK inhibitor trametinib. Disulfiram demonstrated excellent selectivity for LGSOC versus high grade serous ovarian carcinoma comparator lines (P = 0.003 for IC50 comparison), while the tyrosine kinase inhibitor dasatinib demonstrated favourable synergy with trametinib across multiple LGSOC models (maximum zero interaction potency synergy score 46.9). The novel, highly selective Src family kinase (SFK) inhibitor NXP900 demonstrated a similar trametinib synergy profile to dasatinib, suggesting that SFK inhibition is the likely driver of synergy. CONCLUSION: Dasatinib and other SFK inhibitors represent novel candidate treatments for LGSOC and demonstrate synergy with trametinib. Disulfiram represents an additional treatment strategy worthy of investigation.

The prognostic value of MEK pathway-associated estrogen receptor signaling activity for female cancers.

BACKGROUND: Other than for breast cancer, endocrine therapy has not been highly effective for gynecologic cancers. Endocrine therapy resistance in estrogen receptor positive gynecologic cancers is still poorly understood. In this retrospective study, we examined the estrogen receptor (ER) signaling pathway activities of breast, ovarian, endometrial, and cervical cancers to identify those that may predict endocrine therapy responsiveness. METHODS: Clinical and genomic data of women with breast and gynecological cancers were downloaded from cBioPortal for Cancer Genomics. Estrogen receptor alpha (ESR1) expression level and sample-level pathway enrichment scores (EERES) were calculated to classify patients into four groups (low/high ESR1 and low/high EERES). Correlation between ESR1/EERES score and survival was further validated with RNAseq data from low-grade serous ovarian cancer. Pathway analyses were performed among different ESR1/EERES groups to identify genes that correlate with endocrine resistance, which are validated using Cancer Cell Line Encyclopedia gene expression and Genomics of Drug Sensitivity in Cancer data. RESULTS: We identified a novel combined prognostic value of ESR1 expression and the corresponding estrogen response signaling (EERES score) for breast cancer. The combined prognostic value (ESR1/EERES) may be applicable to other gynecologic cancers. More importantly, we discovered that ER signaling can cross-regulate MEK pathway activation. We identified downstream genes in the MEK pathway (EPHA2, INAVA, MALL, MPZL2, PCDH1, and TNFRSF21) that are potential endocrine therapy response biomarkers. CONCLUSION: This study demonstrated that targeting both the ER and the ER signaling activity related MEK pathway may aid the development of endocrine therapy strategies for personalized medicine.

Phase II trial of pembrolizumab and epacadostat in recurrent clear cell carcinoma of the ovary: An NRG oncology study GY016.

INTRODUCTION: Early reports of PD-1 inhibition in ovarian clear cell carcinomas (OCCC) demonstrate promising response. We evaluated the combination of pembrolizumab and IDO-1 inhibitor epacadostat in patients with recurrent OCCC. METHODS: This single arm, two-stage, phase 2 trial included those with measurable disease and 1-3 prior regimens. Patients received intravenous pembrolizumab 200 mg every 3 weeks and oral epacadostat 100 mg twice a day. Primary endpoint was overall response rate (ORR), secondary endpoints were toxicity, progression-free survival (PFS) and overall survival (OS). The study was powered to detect an absolute 25% increase in response (15% to 40%). RESULTS: Between September 28, 2018 and April 10, 2019, 14 patients enrolled at first stage. Rate of accrual was 2.3 patients per month. Median age was 65 years (44-89), 10 (71.4%) had ≥2 prior regimens. ORR was 21% (95% CI 5-51%) within 7 months of study entry with 3 partial responses, and 4 had stable disease (disease control rate 50%). Median PFS was 4.8 months (95% CI: 1.9-9.6), OS 18.9 months (95% CI: 1.9-NR). Most common grade ≥ 3 adverse events were electrolyte abnormalities and gastrointestinal pain, nausea, vomiting, bowel obstruction. In July 2019, the study reached the pre-specified criteria to re-open to second stage; however, the study closed prematurely in February 2021 due to insufficient drug supply. CONCLUSIONS: Pembrolizumab and epacadostat demonstrated an ORR of 21% in this small cohort of recurrent OCCC. The rapid rate of accrual highlights the enthusiasm and need for therapeutic studies in patients with OCCC.

Serial cytoreductive surgery and survival outcomes in recurrent adult-type ovarian granulosa cell tumors.

BACKGROUND: Few studies have evaluated the role of cytoreductive surgery in patients with recurrent adult granulosa cell tumors of the ovary. Despite a multitude of treatment modalities in the recurrent setting, the optimal management strategy is not known. Cytoreductive surgery offers an attractive option for disease confined to the abdomen/pelvis. However, few studies have evaluated the role of surgery compared with systemic therapy alone following the first recurrence and subsequent disease progressions. OBJECTIVE: This study aimed to determine the impact of secondary, tertiary, and quaternary cytoreductive surgery on survival outcomes in recurrent adult granulosa cell tumors of the ovary. STUDY DESIGN: This is a multicenter, retrospective cohort study evaluating patients with recurrent adult granulosa cell tumors of the ovary enrolled in the MD Anderson Rare Gynecologic Malignancy Registry from 1970 to 2022. Study inclusion criteria consisted of histology-proven recurrent disease, at least 1 documented recurrence, and treatment/treatment planning at the MD Anderson Cancer Center or Lyndon B. Johnson General Hospital. The primary exposure was cytoreductive surgery, and the outcomes of interest were progression-free survival and overall survival. Survival analyses were restricted to eligible patients with resectable disease without medical barriers to surgery at each progression episode. Demographic and clinicopathologic characteristics were summarized using descriptive statistics. Progression-free survival (after first, second, and third progression) and overall survival were estimated with methods of Kaplan and Meier, and were modeled via Cox proportional hazards regression. Multivariable analyses were performed for progression-free survival after first progression and overall survival. RESULTS: Among the 369 patients with adult granulosa cell tumors of the ovary in the registry, 149 patients met the study inclusion criteria. Secondary cytoreductive surgery was associated with a significant improvement in progression-free survival on univariable (hazard ratio, 0.37; 95% confidence interval, 0.17-0.81, P=.01) and multivariable analyses (hazard ratio, 0.42; 95% confidence interval, 0.19-0.92; P=.03). Those who underwent secondary cytoreductive surgery had a significantly improved median overall survival compared with those who did not undergo cytoreductive surgery (181.92 vs 61.56 months, respectively; P=.002). Overall survival benefit remained statistically significant on multivariable analysis (hazard ratio, 0.28; 95% confidence interval, 0.11-0.67; P=.004). Tertiary cytoreductive surgery was similarly associated with a significant improvement in progression-free survival (hazard ratio, 0.43; 95% confidence interval, 0.26-0.70; P=.001). Despite a similar trend, quaternary cytoreductive surgery was not associated with a significant improvement in progression-free survival (hazard ratio, 0.74; 95% confidence interval, 0.42-1.26; P=.27). CONCLUSION: Among those with resectable disease and no medical contraindications to surgery, cytoreductive surgery may have a beneficial impact on progression-free survival and overall survival in patients with recurrent adult granulosa cell tumors of the ovary.

Randomized phase 2 trial of tremelimumab and durvalumab in combination versus sequentially in recurrent platinum-resistant ovarian cancer.

BACKGROUND: Single-agent immune checkpoint inhibitors (ICIs) have demonstrated limited responses in recurrent ovarian cancer; however, 30%-40% of patients achieve stable disease. The primary objective was to estimate progression-free survival (PFS) after sequential versus combination cytotoxic T-lymphocyte antigen 4 and programmed death ligand 1 ICIs in patients with platinum-resistant high-grade serous ovarian cancer (HGSOC). METHODS: Patients were randomized to a sequential arm (tremelimumab followed by durvalumab on progression) or a combination arm (tremelimumab plus durvalumab, followed by durvalumab) via a Bayesian adaptive design that made it more likely for patients to be randomized to the more effective arm. The primary end point was immune-related PFS (irPFS). RESULTS: Sixty-one subjects were randomized to sequential (n = 38) or combination therapy (n = 23). Thirteen patients (34.2%) in the sequential arm received durvalumab. There was no difference in PFS in the sequential arm (1.84 months; 95% CI, 1.77-2.17 months) compared with the combination arm (1.87 months; 95% CI, 1.77-2.43 months) (p = .402). In the sequential arm, no responses were observed, although 12 patients (31.6%) demonstrated stable disease. In the combination arm, two patients (8.7%) had partial response, whereas one patient (4.4%) had stable disease. Adverse events were consistent with those previously reported for ICIs. Patient-reported outcomes were similar in both arms. CONCLUSIONS: There was no difference in irPFS for combination tremelimumab plus durvalumab compared to tremelimumab alone (administered as part of a sequential treatment strategy) in a heavily pretreated population of patients with platinum-resistant HGSOC. Response rates were comparable to prior reports, although the combination regimen did not add significant benefit, as has been previously described.

Impact of adjuvant chemotherapy on the overall survival of patients with advanced-stage low-grade serous ovarian carcinoma following primary cytoreductive surgery.

OBJECTIVE: To investigate the use and outcomes of adjuvant chemotherapy for patients with advanced-stage low-grade serous ovarian carcinoma following primary cytoreductive surgery. METHODS: Patients diagnosed between 2010 and 2015 with International Federation of Gynecology and Obstetrics stage II-IV low-grade serous ovarian carcinoma who underwent primary debulking surgery with known residual disease status and had at least 1 month of follow-up were identified in the National Cancer Database. Adjuvant chemotherapy was defined as receipt of chemotherapy within 6 months of surgery. Overall survival was evaluated using the Kaplan-Meier method and compared with the log-rank test. A Cox model was constructed to control for a priori-selected confounders. A systematic review of the literature was also performed. RESULTS: In total, 618 patients with stage II-IV low-grade serous ovarian carcinoma who underwent primary cytoreductive surgery were identified; 501 (81.1%) patients received adjuvant chemotherapy, while 117 (18.9%) patients did not. The median follow-up of the present cohort was 47.97 months. There was no difference in overall survival between patients who did and did not receive adjuvant chemotherapy (p=0.78; 4-year overall survival rates were 77.5% and 76.1%, respectively). After controlling for patient age, medical co-morbidities, disease stage, and residual disease status, administration of adjuvant chemotherapy was not associated with better overall survival (HR=0.87, 95% CI 0.55 to 1.38). Based on data from three retrospective studies, omission of adjuvant chemotherapy following cytoreductive surgery was not associated with worse progression-free survival benefit (HR=1.25, 95% CI 0.80 to 1.95) for patients with stage III-V low-grade serous ovarian carcinoma. CONCLUSIONS: Adjuvant chemotherapy may not be associated with an overall survival benefit for patients with advanced-stage low-grade serous ovarian carcinoma following primary cytoreductive surgery.

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.

Uptake and Outcomes of Neoadjuvant Chemotherapy Among US Patients With Less Common Epithelial Ovarian Carcinomas.

Importance: Randomized clinical trials examining the effectiveness of neoadjuvant chemotherapy (NACT) for advanced ovarian cancer predominantly included patients with high-grade serous carcinomas. The use and outcomes of NACT in less common epithelial carcinomas are understudied. Objective: To investigate the uptake and survival outcomes in treatment with NACT for less common histologic subtypes of epithelial ovarian cancer. Design, Setting, and Participants: A retrospective cohort study and systematic literature review with meta-analysis was conducted using the National Cancer Database from 2006 to 2017 and the National Cancer Institute's Surveillance, Epidemiology, and End Results Program from 2006 to 2019. Data analysis was performed from July 2022 to April 2023. The evaluation included patients with stage III to IV ovarian cancer with clear cell, mucinous, or low-grade serous histologic subtypes who received multimodal treatment with surgery and chemotherapy. Exposures: Exposure assignment per the sequence of treatment: primary debulking surgery (PDS) followed by chemotherapy (PDS group) or NACT followed by interval surgery (NACT group). Main Outcomes and Measures: Temporal trends and characteristics of NACT use were assessed using multivariable analysis, and overall survival (OS) was assessed with the inverse probability of treatment weighting propensity score. Results: A total of 3880 patients were examined in the National Cancer Database including 1829 women (median age, 56 [IQR, 49-63] years) with clear cell, 1156 women (median age, 53 [IQR, 42-64] years) with low-grade serous, and 895 women (median age, 57 [IQR, 48-66] years) with mucinous carcinomas. NACT use increased in patients with clear cell (from 10.2% to 16.2%, 58.8% relative increase; P < .001 for trend) or low-grade serous (from 7.7% to 14.2%, 84.4% relative increase; P = .007 for trend) carcinoma during the study period. This association remained consistent in multivariable analysis. NACT use also increased, but nonsignificantly, in mucinous carcinomas (from 8.6% to 13.9%, 61.6% relative increase; P = .07 for trend). Across the 3 histologic subtypes, older age and stage IV disease were independently associated with NACT use. In a propensity score-weighted model, the NACT and PDS groups had comparable OS for clear cell (4-year rates, 31.4% vs 37.7%; hazard ratio [HR], 1.12; 95% CI, 0.95-1.33) and mucinous (27.0% vs 26.7%; HR, 0.90; 95% CI, 0.68-1.19) carcinomas. For patients with low-grade serous carcinoma, NACT was associated with decreased OS compared with PDS (4-year rates, 56.4% vs 81.0%; HR, 2.12; 95% CI, 1.55-2.90). Increasing NACT use and histologic subtype-specific survival association were also found in the Surveillance, Epidemiology, and End Results Program cohort (n = 1447). A meta-analysis of 4 studies, including the current study, observed similar OS associations for clear cell (HR, 1.13; 95% CI, 0.96-1.34; 2 studies), mucinous (HR, 0.93; 95% CI, 0.71-1.21; 2 studies), and low-grade serous (HR, 2.11; 95% CI, 1.63-2.74; 3 studies) carcinomas. Conclusions and Relevance: Despite the lack of data on outcomes of NACT among patients with less common carcinomas, this study noted that NACT use for advanced disease has gradually increased in the US. Primary chemotherapy for advanced-stage, low-grade serous ovarian cancer may be associated with worse survival compared with PDS.

The effect of older age on treatment outcomes in women with advanced ovarian cancer receiving chemotherapy: An NRG-Oncology/Gynecologic Oncology Group (GOG-0182-ICON5) ancillary study.

OBJECTIVE: To assess the effect of age on overall survival (OS) in women with ovarian cancer receiving chemotherapy. Secondary objectives were to describe the effect of age on treatment compliance, toxicities, progression free survival (PFS), time from surgery to chemotherapy, and rates of optimal cytoreduction. METHODS: Women enrolled in GOG 0182-ICON5 with stage III or IV epithelial ovarian cancer (EOC) who underwent surgery and chemotherapy between 2001 and 2004 were included. Patients were divided into ages <70 and ≥ 70 years. Baseline characteristics, treatment compliance, toxicities, and clinical outcomes were compared. RESULTS: We included a total of 3686 patients, with 620 patients (16.8%) ≥ 70 years. OS was 37.2 months in older compared to 45.0 months in younger patients (HR 1.21, 95% CI, 1.09-1.34, p < 0.001). Older patients had an increased risk of cancer-specific-death (HR 1.16, 95% CI, 1.04-1.29) as well as non-cancer related deaths (HR 2.78, 95% CI, 2.00-3.87). Median PFS was 15.1 months in older compared to 16.0 months in younger patients (HR 1.10, 95% CI, 1.00-1.20, p = 0.056). In the carboplatin/paclitaxel arm, older patients were just as likely to complete therapy and more likely to develop grade ≥ 2 peripheral neuropathy (35.7 vs 19.7%, p < 0.001). Risk of other toxicities remained equal between groups. CONCLUSIONS: In women with advanced EOC receiving chemotherapy, age ≥ 70 was associated with shorter OS and cancer specific survival. Older patients receiving carboplatin and paclitaxel reported higher rates of grade ≥ 2 neuropathy but were not more likely to suffer from other chemotherapy related toxicities. Clintrials.gov: NCT00011986.

Carboplatin dosing in the treatment of ovarian cancer: An NRG oncology group study.

OBJECTIVE: To determine the effects of using National Comprehensive Cancer Network (NCCN) guidelines to estimate renal function on carboplatin dosing and explore adverse effects associated with a more accurate estimation of lower creatinine clearance (CrCl). METHODS: Retrospective data were obtained for 3830 of 4312 patients treated on GOG182 (NCT00011986)-a phase III trial of platinum-based chemotherapy for advanced-stage ovarian cancer. Carboplatin dose per patient on GOG182 was determined using the Jelliffe formula. We recalculated CrCl to determine dosing using Modification of Diet in Renal Disease (MDRD) and Cockcroft-Gault (with/without NCCN recommended modifications) formulas. Associations between baseline CrCl and toxicity were described using the area under the receiver operating characteristic curve (AUC). Sensitivity and positive predictive values described the model's ability to discriminate between subjects with/without the adverse event. RESULTS: AUC statistics (range, 0.52-0.64) showed log(CrClJelliffe) was not a good predictor of grade ≥3 adverse events (anemia, thrombocytopenia, febrile neutropenia, auditory, renal, metabolic, neurologic). Of 3830 patients, 628 (16%) had CrCl <60 mL/min. Positive predictive values for adverse events ranged from 1.8%-15%. Using the Cockcroft-Gault, Cockcroft-Gault with NCCN modifications, and MDRD (instead of Jelliffe) formulas to estimate renal function resulted in a >10% decrease in carboplatin dosing in 16%, 32%, and 5.2% of patients, respectively, and a >10% increase in carboplatin dosing in 41%, 9.6% and 12% of patients, respectively. CONCLUSION: The formula used to estimate CrCl affects carboplatin dosing. Estimated CrCl <60 mL/min (by Jelliffe) did not accurately predict adverse events. Efforts continue to better predict renal function. Endorsing National Cancer Institute initiatives to broaden study eligibility, our data do not support a minimum threshold CrCl <60 mL/min as an exclusion criterion from clinical trials.

Comparative Tumor Microenvironment Analysis of Primary and Recurrent Ovarian Granulosa Cell Tumors.

Adult-type granulosa cell tumors (aGCT) are rare ovarian sex cord tumors with few effective treatments for recurrent disease. The objective of this study was to characterize the tumor microenvironment (TME) of primary and recurrent aGCTs and to identify correlates of disease recurrence. Total RNA sequencing (RNA-seq) was performed on 24 pathologically confirmed, cryopreserved aGCT samples, including 8 primary and 16 recurrent tumors. After read alignment and quality-control filtering, DESeq2 was used to identify differentially expressed genes (DEG) between primary and recurrent tumors. Functional enrichment pathway analysis and gene set enrichment analysis was performed using "clusterProfiler" and "GSVA" R packages. TME composition was investigated through the analysis and integration of multiple published RNA-seq deconvolution algorithms. TME analysis results were externally validated using data from independent previously published RNA-seq datasets. A total of 31 DEGs were identified between primary and recurrent aGCTs. These included genes with known function in hormone signaling such as LHCGR and INSL3 (more abundant in primary tumors) and CYP19A1 (more abundant in recurrent tumors). Gene set enrichment analysis revealed that primarily immune-related and hormone-regulated gene sets expression was increased in recurrent tumors. Integrative TME analysis demonstrated statistically significant depletion of cancer-associated fibroblasts in recurrent tumors. This finding was confirmed in multiple independent datasets. IMPLICATIONS: Recurrent aGCTs exhibit alterations in hormone pathway gene expression as well as decreased infiltration of cancer-associated fibroblasts, suggesting dual roles for hormonal signaling and TME remodeling underpinning disease relapse.

Clinical outcomes of leuprolide acetate in the treatment of recurrent ovarian granulosa cell tumors.

BACKGROUND: The optimal treatment of recurrent ovarian granulosa cell tumors is not known. Preclinical studies and small case series have suggested direct antitumor activity of gonadotropin-releasing hormone agonists in the treatment of this disease, but little is known about the efficacy and safety of this approach. OBJECTIVE: This study aimed to describe patterns of use and clinical outcomes of leuprolide acetate in a cohort of patients with recurrent granulosa cell tumors. STUDY DESIGN: This was a retrospective cohort study of patients enrolled in the Rare Gynecologic Malignancy Registry at a large cancer referral center and affiliated county hospital. Patients meeting inclusion criteria had a diagnosis of recurrent granulosa cell tumor and received either leuprolide acetate or traditional chemotherapy as cancer treatment. Outcomes were separately examined for leuprolide acetate used as adjuvant treatment, maintenance therapy, and the treatment of gross disease. Demographic and clinical data were summarized using descriptive statistics. Progression-free survival was calculated from the initiation of treatment to the date of disease progression or death, and compared between groups with the log-rank test. The 6-month clinical benefit rate was defined as the percentage of patients without disease progression 6 months after starting therapy. RESULTS: Sixty-two patients received a total of 78 leuprolide acetate-containing therapy courses, owing to 16 instances of retreatment. Of these 78 courses, 57 (73%) were for treatment of gross disease, 10 (13%) were adjuvant to tumor reductive surgery, and 11 (14%) were for maintenance therapy. Patients had received a median of 2 (interquartile range, 1-3) systemic therapy regimens before their first leuprolide acetate treatment. Tumor reductive surgery (100% [62/62]) and platinum-based chemotherapy (81% [50/62]) were common before first leuprolide acetate exposure. The median duration of leuprolide acetate therapy was 9.6 months (interquartile range, 4.8-16.5). Nearly half of the therapy courses were single-agent leuprolide acetate (49% [38/78]). Combination regimens most often included an aromatase inhibitor (23% [18/78]). Disease progression was the most common cause of discontinuation (77% [60/78]); only 1 patient (1%) discontinued leuprolide acetate because of adverse events. In the treatment of gross disease, the 6-month clinical benefit rate for first use of leuprolide acetate was 66% (95% confidence interval, 54-82). Median progression-free survival was not statistically different compared with that which followed chemotherapy (10.3 months [95% confidence interval, 8.0-16.0] vs 8.0 months [95% confidence interval, 5.0-15.3]; P=.3). CONCLUSION: In a large cohort of patients with recurrent granulosa cell tumors, the 6-month clinical benefit rate of first-time leuprolide acetate treatment of gross disease was 66% and progression-free survival was comparable to patients treated with chemotherapy. Leuprolide acetate regimens were heterogeneous, but significant toxicity was rare. These results support leuprolide acetate as safe and effective for the treatment of relapsed adult granulosa cell tumors in the second line and beyond.

Novel therapeutics in low-grade serous ovarian cancer.

Low-grade serous ovarian cancer is a rare subtype of epithelial ovarian cancer clinically characterized by younger age at diagnosis, relative chemoresistance, and prolonged survival compared with its high-grade serous counterpart. It is molecularly characterized by estrogen and progesterone receptor positivity, aberrations in the MAPK (mitogen-activated protein kinase) pathway, and wild-type TP53 expression pattern. As research into low-grade serous ovarian cancer as a distinct entity has been able to accelerate independently, we have learned more about its unique pathogenesis, oncogenic drivers, and opportunities for novel therapeutics. In the primary setting, cytoreductive surgery in combination with platinum-based chemotherapy remain the standard of care. However, low-grade serous ovarian cancer has demonstrated relative chemoresistance in the primary and recurrent settings. Endocrine therapy is also commonly utilized in the maintenance and recurrent settings and is being evaluated in the adjuvant setting. Given the many similarities of low-grade serous ovarian cancer to luminal breast cancer, many recent studies have utilized similar therapeutic strategies including endocrine therapy combinations with CDK (cyclin-dependent kinase) 4/6 inhibitors. Additionally, recent trials have investigated combination therapies targeting the MAPK pathway, including MEK (mitogen-activated protein kinase kinase), BRAF (v-raf murine sarcoma viral oncogene homolog B1), FAK (focal adhesion kinase), and PI3K (phosphatidylinositol 3-kinase) inhibition. In this review, we will outline these novel therapeutic strategies for low-grade serous ovarian cancer.

Selinexor in combination with weekly paclitaxel in patients with metastatic solid tumors: Results of an open label, single-center, multi-arm phase 1b study with expansion phase in ovarian cancer.

OBJECTIVE: Selinexor is a first-in-class, oral selective inhibitor of nuclear export (SINE) compound which blocks Exportin-1 (XPO1). Our objective was to determine maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of selinexor and weekly paclitaxel. METHODS: This was an open label, single-center, multi-arm phase 1b study utilizing a "3 + 3" design and a "basket-type" expansion in recurrent solid tumors. Selinexor (60 mg or 80 mg twice weekly orally) and weekly paclitaxel (80 mg IV 2 week on, 1 week off) were one of 13 parallel arms. Efficacy was evaluated using RECIST version 1.1. RESULTS: All 35 patients treated were evaluable for toxicity and 31 (88%) were evaluable for response. Patient diagnoses included platinum-resistant/refractory ovarian (n = 28), breast (n = 4), prostate (n = 2), and cervical (n = 1) cancer. Patients had a median of four prior therapies (range 1-10), and 47% had a prior taxane in the recurrent setting. There were no DLTs and 60 mg was chosen as the RP2D due to long-term tolerability. Ninety-seven percent of patients had at least one treatment-emergent adverse event (TEAE), and the most common grade ≥ 3 TEAE were neutropenia (46%), anemia (31%), and nausea (21%). Among 24 evaluable patients with ovarian cancer, response rate was 17%, CBR was 58%, and median PFS was 6.8 months (95% CI 3.7, not reached (NR)). CONCLUSIONS: Oral selinexor in combination with weekly paclitaxel demonstrated promising clinical activity with manageable toxicity. This combination should be considered for further exploration in a randomized study, especially in ovarian malignancies.

Integrated multi-omic analysis of low-grade ovarian serous carcinoma collected from short and long-term survivors.

BACKGROUND: Low-grade serous ovarian cancer (LGSOC) is a rare disease that occurs more frequently in younger women than those with high-grade disease. The current treatment is suboptimal and a better understanding of the molecular pathogenesis of this disease is required. In this study, we compared the proteogenomic analyses of LGSOCs from short- and long-term survivors (defined as < 40 and > 60 months, respectively). Our goal was to identify novel mutations, proteins, and mRNA transcripts that are dysregulated in LGSOC, particularly in short-term survivors. METHODS: Initially, targeted sequencing of 409 cancer-related genes was performed on 22 LGSOC and 6 serous borderline ovarian tumor samples. Subsequently, whole-genome sequencing analysis was performed on 14 LGSOC samples (7 long-term survivors and 7 short-term survivors) with matched normal tissue samples. RNA sequencing (RNA-seq), quantitative proteomics, and phosphoproteomic analyses were also performed. RESULTS: We identified single-nucleotide variants (SNVs) (range: 5688-14,833 per sample), insertion and deletion variants (indels) (range: 880-1065), and regions with copy number variants (CNVs) (range: 62-335) among the 14 LGSOC samples. Among all SNVs and indels, 2637 mutation sites were found in the exonic regions. The allele frequencies of the detected variants were low (median12%). The identified recurrent nonsynonymous missense mutations included KRAS, NRAS, EIF1AX, UBR5, and DNM3 mutations. Mutations in DNM3 and UBR5 have not previously been reported in LGSOC. For the two samples, somatic DNM3 nonsynonymous missense mutations in the exonic region were validated using Sanger sequencing. The third sample contained two missense mutations in the intronic region of DNM3, leading to a frameshift mutation detected in RNA transcripts in the RNA-seq data. Among the 14 LGSOC samples, 7754 proteins and 9733 phosphosites were detected by global proteomic analysis. Some of these proteins and signaling pathways, such as BST1, TBXAS1, MPEG1, HBA1, and phosphorylated ASAP1, are potential therapeutic targets. CONCLUSIONS: This is the first study to use whole-genome sequencing to detect somatic mutations in LGSOCs with matched normal tissues. We detected and validated novel mutations in DNM3, which were present in 3 of the 14 samples analyzed. Additionally, we identified novel indels, regions with CNVs, dysregulated mRNA, dysregulated proteins, and phosphosites that are more prevalent in short-term survivors. This integrated proteogenomic analysis can guide research into the pathogenesis and treatment of LGSOC.

A phase II evaluation of temsirolimus with carboplatin and paclitaxel followed by temsirolimus consolidation in clear cell ovarian cancer: An NRG oncology trial.

OBJECTIVE: The primary objective of the study was to estimate the 12-month progression-free survival (PFS) for carboplatin/paclitaxel + temsirolimus in women with newly diagnosed clear cell ovarian cancer (CCOC), compared to historical controls in this patient population. METHODS: Patients with Stage III or IV CCOC were treated with Paclitaxel 175 mg/m2 on Day 1, Carboplatin AUC 6 Day 1, and temsirolimus (CCI-779) 25 mg IV Days 1 and 8 every 3 weeks for Cycles 1-6 or disease progression, followed by consolidation therapy with temsirolimus 25 mg Days 1, 8, and 15 every 3 weeks cycles 7-17 or until disease progression. RESULTS: Ninety patients were accrued to the study: 45 in the US and Korea (US/Korea) and 45 in Japan. Twenty-two percent received ≤6 cycles of therapy while 28% completed all 17 cycles of chemotherapy. Median PFS (OS) was 11 (23) months for US/Korea and 12 (26) months for Japan. In the US, none of suboptimally debulked patients had PFS >12 months, and 49% of optimal patients did, compared to 25% and 59% in Japan. Most common grade 3-4 adverse events were neutropenia, leukopenia, anemia, thrombocytopenia, hypertension, hypertriglyceridemia, and oral mucositis. CONCLUSION: The carboplatin/paclitaxel + temsirolimus regimen was well tolerated. In optimally debulked patients, 54% had a PFS >12 months. This regimen did not statistically significantly increase PFS at 12 months compared to historical controls. No statistically significant differences in PFS or OS were observed between US/Korea vs Japan, or Asians vs non-Asians.

Contemporary primary treatment of women with stage II-IV low-grade serous ovarian/peritoneal cancer (LGSOC): Determinants of relapse and disease-free survival.

OBJECTIVE: The purpose of the present study is to describe a cohort who received contemporary primary treatment for stage II-IV low-grade serous ovarian/peritoneal cancer (LGSOC), including patient characteristics and determinants of relapse and disease-free survival. METHODS: The study included 99 patients: 1) with pathologically confirmed stage II-IV LGSOC of the ovary or peritoneum, 2) who underwent primary treatment consisting of cytoreductive surgery and either a) platinum/taxane chemotherapy followed by aromatase inhibitor maintenance therapy or b) aromatase inhibitor monotherapy, and 3) for whom there was availability of clinical data. Descriptive statistics were used to characterize clinicodemographic features. Subgroups were compared for PFS and OS. Multivariable Cox regression analyses were performed. RESULTS: Median PFS for the entire cohort was 56.8 months (95% CI, 41.3-NE), and median OS was 130.7 months (95% CI, 115.0-146.4). Forty-nine of 99 (49.5%) patients have relapsed to date. For these 49 patients, median time from diagnosis to relapse was 29.6 months (95% CI, 24.6-33.1) (range, 5.4-69.1 months). Only 1/49 (2%) patients who relapsed did so >5 years from diagnosis. Fifty (50.0%) patients have not experienced disease progression or relapse. Median follow-up time for these 50 patients is 86.2 months (range, 25.3-169.0). Thirty-three of the 50 (66.0%) have been followed for >5 years from diagnosis. On regression analyses, factors associated with improved patient outcomes-either PFS, OS, or both-included no gross residual disease, normal serum CA 125 at diagnosis, primary peritoneal site, and presence of extensive psammomatous calcifications. CONCLUSIONS: This is the first report to describe the clinicopathologic features and outcomes of women with stage II-IV LGSOC who received contemporary primary therapy.

NCCN Guidelines® Insights: Ovarian Cancer, Version 3.2022.

Epithelial ovarian cancer is the leading cause of death from gynecologic cancer in the United States, with less than half of patients living >5 years following diagnosis. The NCCN Guidelines for Ovarian Cancer provide recommendations for the diagnosis, evaluation, treatment, and follow-up for patients with ovarian, fallopian tube, and primary peritoneal cancers. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines, including revised guidance on alternative chemotherapy regimens for patients with advanced age and/or comorbidities, a new algorithm for recurrent low-grade serous carcinoma based on developing research and novel therapeutic agents, and updated language regarding tumor molecular analysis applications in ovarian cancer.

The genomic landscape of low-grade serous ovarian/peritoneal carcinoma and its impact on clinical outcomes.

OBJECTIVE: Low-grade serous carcinoma (LGSOC) is a rare epithelial ovarian/peritoneal cancer characterized by younger age at diagnosis, relative chemoresistance, prolonged overall survival (OS), and mutations in the mitogen activated protein kinase (MAPK) pathway compared to high-grade serous carcinoma. We describe the genomic profile of LGSOC by next generation sequencing (NGS) and evaluated its potential relationship to clinical outcomes. METHODS: The study included 215 women with LGSOC with: 1) pathologically confirmed LGSOC, 2) availability of NGS data, and 3) adequate clinical data. Clinical subgroups were compared for progression-free survival (PFS) and OS. Multivariable Cox regression analysis was performed. RESULTS: Median age at diagnosis was 46.6 years. The majority had a stage III ovarian primary. One or more mutations were identified in 140 (65.1%) cases; 75 (34.9%) had none. The most common mutations were KRAS (n = 71; 33.0%), NRAS (n = 24; 11.2%), and BRAF (n = 18; 8.4%). Patients with MAPK-mutated tumors (n = 113) (52.6%) had a significantly longer OS compared to those with tumors lacking MAPK pathway mutations (n = 102) (47.4%) [median OS, 147.8 months (95% CI,119.0-176.6) versus 89.5 months (95% CI, 61.4-117.7) (p = 0.01)], respectively. Median OS for patients with MAPK-mutated tumors was also significantly better than for patients whose tumors had no mutations (n = 75) [median OS, 147.8 months (95% CI, 119.0-176.6) versus 78.0 months (95% CI, 57.6-98.3)], respectively (p = 0.001). Median OS for patients with non-MAPK-mutated tumors (n = 27) was 125.1 months (95% CI, 83.9-166.3). In multivariable analysis, having a MAPK mutation was associated with improved OS. CONCLUSIONS: Patients with MAPK-mutated tumors have a significantly improved OS compared to those without MAPK-mutated tumors.

Trametinib versus standard of care in patients with recurrent low-grade serous ovarian cancer (GOG 281/LOGS): an international, randomised, open-label, multicentre, phase 2/3 trial.

BACKGROUND: Low-grade serous carcinoma of the ovary or peritoneum is characterised by MAPK pathway aberrations and its reduced sensitivity to chemotherapy relative to high-grade serous carcinoma. We compared the MEK inhibitor trametinib to physician's choice standard of care in patients with recurrent low-grade serous carcinoma. METHODS: This international, randomised, open-label, multicentre, phase 2/3 trial was done at 84 hospitals in the USA and UK. Eligible patients were aged 18 years or older with recurrent low-grade serous carcinoma and measurable disease, as defined by Response Evaluation Criteria In Solid Tumors version 1.1, had received at least one platinum-based regimen, but not all five standard-of-care drugs, and had received an unlimited number of previous regimens. Patients with serous borderline tumours or tumours containing low-grade serous and high-grade serous carcinoma were excluded. Eligible patients were randomly assigned (1:1) to receive either oral trametinib 2 mg once daily (trametinib group) or one of five standard-of-care treatment options (standard-of-care group): intravenous paclitaxel 80 mg/m2 by body surface area on days 1, 8, and 15 of every 28-day cycle; intravenous pegylated liposomal doxorubicin 40-50 mg/m2 by body surface area once every 4 weeks; intravenous topotecan 4 mg/m2 by body surface area on days 1, 8, and 15 of every 28-day cycle; oral letrozole 2·5 mg once daily; or oral tamoxifen 20 mg twice daily. Randomisation was stratified by geographical region (USA or UK), number of previous regimens (1, 2, or ≥3), performance status (0 or 1), and planned standard-of-care regimen. The primary endpoint was investigator-assessed progression-free survival while receiving randomised therapy, as assessed by imaging at baseline, once every 8 weeks for 15 months, and then once every 3 months thereafter, in the intention-to-treat population. Safety was assessed in patients who received at least one dose of study therapy. This trial is registered with ClinicalTrials.gov, NCT02101788, and is active but not recruiting. FINDINGS: Between Feb 27, 2014, and April 10, 2018, 260 patients were enrolled and randomly assigned to the trametinib group (n=130) or the standard-of-care group (n=130). At the primary analysis, there were 217 progression-free survival events (101 [78%] in the trametinib group and 116 [89%] in the standard-of-care group). Median progression-free survival in the trametinib group was 13·0 months (95% CI 9·9-15·0) compared with 7·2 months (5·6-9·9) in the standard-of-care group (hazard ratio 0·48 [95% CI 0·36-0·64]; p<0·0001). The most frequent grade 3 or 4 adverse events in the trametinib group were skin rash (17 [13%] of 128), anaemia (16 [13%]), hypertension (15 [12%]), diarrhoea (13 [10%]), nausea (12 [9%]), and fatigue (ten [8%]). The most frequent grade 3 or 4 adverse events in the standard-of-care group were abdominal pain (22 [17%]), nausea (14 [11%]), anaemia (12 [10%]), and vomiting (ten [8%]). There were no treatment-related deaths. INTERPRETATION: Trametinib represents a new standard-of-care option for patients with recurrent low-grade serous carcinoma. FUNDING: NRG Oncology, Cancer Research UK, Target Ovarian Cancer, and Novartis.