A phase 2 study of anastrozole in patients with oestrogen receptor and/progesterone receptor positive recurrent/metastatic granulosa cell tumours/sex-cord stromal tumours of the ovary: The PARAGON/ANZGOG 0903 trial.

BACKGROUND: Hormonal therapies are commonly prescribed to patients with metastatic granulosa cell tumours (GCT), based on high response rates in small retrospective studies. Aromatase inhibitors (AIs) are reported to have high response rates and an accepted treatment option. We report the results of a phase 2 trial of an AI in recurrent/metastatic GCTs. METHODS: 41 patients with recurrent ER/PR + ve GCT received anastrozole 1 mg daily until progression or unacceptable toxicity. The primary endpoint was clinical benefit rate (CBR) at 12 weeks, evaluated by RECIST1.1 criteria. Secondary endpoints included progression-free survival (PFS), CBR duration, quality of life and toxicity. RESULTS: The CBR at 12 weeks in 38 evaluable patients was 78.9%, which included one (2.6%; 95% CI: 0.5-13.5%) partial response and 76.3% stable disease. Two additional patients without measurable disease were stable, based on inhibin. Median PFS was 8.6 m (95% CI 5.5-13.5 m). There were delayed responses observed after 12 weeks with a total of 4 pts. (10.5%; 95% CI 4.2%-24.1%) with a RECIST partial response; 23 (59%) patients were progression-free at 6 months. The adverse effects were predominantly low grade. CONCLUSIONS: This is the first prospective trial of hormonal therapy in GCTs. Although there was a high CBR, the objective response rate to anastrozole was much lower than the pooled response rates of >70% to AIs reported in most retrospective series and case reports. PARAGON demonstrates the importance of prospective trials in rare cancers and the need to reconsider the role of AIs as single agents in GCTs.

Development and Validation of the Gene Expression Predictor of High-grade Serous Ovarian Carcinoma Molecular SubTYPE (PrOTYPE).

PURPOSE: Gene expression-based molecular subtypes of high-grade serous tubo-ovarian cancer (HGSOC), demonstrated across multiple studies, may provide improved stratification for molecularly targeted trials. However, evaluation of clinical utility has been hindered by nonstandardized methods, which are not applicable in a clinical setting. We sought to generate a clinical grade minimal gene set assay for classification of individual tumor specimens into HGSOC subtypes and confirm previously reported subtype-associated features. EXPERIMENTAL DESIGN: Adopting two independent approaches, we derived and internally validated algorithms for subtype prediction using published gene expression data from 1,650 tumors. We applied resulting models to NanoString data on 3,829 HGSOCs from the Ovarian Tumor Tissue Analysis consortium. We further developed, confirmed, and validated a reduced, minimal gene set predictor, with methods suitable for a single-patient setting. RESULTS: Gene expression data were used to derive the predictor of high-grade serous ovarian carcinoma molecular subtype (PrOTYPE) assay. We established a de facto standard as a consensus of two parallel approaches. PrOTYPE subtypes are significantly associated with age, stage, residual disease, tumor-infiltrating lymphocytes, and outcome. The locked-down clinical grade PrOTYPE test includes a model with 55 genes that predicted gene expression subtype with >95% accuracy that was maintained in all analytic and biological validations. CONCLUSIONS: We validated the PrOTYPE assay following the Institute of Medicine guidelines for the development of omics-based tests. This fully defined and locked-down clinical grade assay will enable trial design with molecular subtype stratification and allow for objective assessment of the predictive value of HGSOC molecular subtypes in precision medicine applications.See related commentary by McMullen et al., p. 5271.

Clinical factors of response in patients with advanced ovarian cancer participating in early phase clinical trials.

Drug resistance to conventional anticancer therapies is almost inevitable in patients with advanced ovarian cancer (AOC), limiting their available treatment options. Novel phase I trial therapies within a dedicated drug development unit may represent a viable alternative; however, there is currently little evidence for patient outcomes in such patients. To address this, we undertook a retrospective review of patients with AOC allocated to phase I trials in the Drug Development Unit at Royal Marsden Hospital (RMH) between June 1998 and October 2010. A total of 200 AOC patients with progressive disease were allocated to ≥1 trial each, with a total of 281 allocations. Of these, 135 (68%) patients commenced ≥1 trial (mean 1.4 [1-8]), totaling 216 allocated trials; 65 (32%) patients did not start due to deterioration resulting from rapidly progressive disease (63 patients) or patient choice (2 patients). Response Evaluation Criteria in Solid Tumours (RECIST) complete/partial responses (CR/PR) were observed in 43 (20%) of those starting trials, including those on poly(ADP-ribose) polymerase (PARP) inhibitors (18/79 [23%]), antiangiogenics (9/65 [14%]) and chemotherapy combinations (14/43 [33%]). Factors associated with CR/PR included: fewer prior treatments, platinum-sensitive disease, CR/PR with prior therapy, (the United States-based) Eastern Cooperative Oncology Group (ECOG) performance status score, fewer metastatic sites, higher albumin and haemoglobin levels, lower white cell counts and baseline CA125 levels, germline BRCA1/2 mutations and better RMH Prognostic Score. Mean survival was 32° months for patients who achieved CR/PR. Treatments were generally well tolerated. Most patients with AOC (134/200 [67%]) received ≥1 subsequent line of therapy after phase I trials. Our data suggest that phase I trial referrals should be considered earlier in the AOC treatment pathway and before the onset of rapid disease progression particularly with the emergence of promising novel agents in the era of precision medicine.

Identification of 12 new susceptibility loci for different histotypes of epithelial ovarian cancer.

To identify common alleles associated with different histotypes of epithelial ovarian cancer (EOC), we pooled data from multiple genome-wide genotyping projects totaling 25,509 EOC cases and 40,941 controls. We identified nine new susceptibility loci for different EOC histotypes: six for serous EOC histotypes (3q28, 4q32.3, 8q21.11, 10q24.33, 18q11.2 and 22q12.1), two for mucinous EOC (3q22.3 and 9q31.1) and one for endometrioid EOC (5q12.3). We then performed meta-analysis on the results for high-grade serous ovarian cancer with the results from analysis of 31,448 BRCA1 and BRCA2 mutation carriers, including 3,887 mutation carriers with EOC. This identified three additional susceptibility loci at 2q13, 8q24.1 and 12q24.31. Integrated analyses of genes and regulatory biofeatures at each locus predicted candidate susceptibility genes, including OBFC1, a new candidate susceptibility gene for low-grade and borderline serous EOC.