Paul Harnett

The use of intraperitoneal chemotherapy for advanced ovarian cancer – The experience of a tertiary referral centre

BackgroundPlatinum‐based chemotherapy is the backbone of the medical management of ovarian cancer. The dose, route and timing of treatment are ongoing areas of debate. Intraperitoneal (IP) chemotherapy is an alternative delivery method treatment to the conventional intravenous (IV) route for patients with epithelial ovarian cancer, with efficacy supported by Level 1 evidence.AimsTo compare the outcomes and feasibility of IP to IV delivery of platinum‐based chemotherapy in patients with advanced epithelial ovarian cancer.Materials and MethodsIn a single institution, patients receiving adjuvant chemotherapy (IP and IV) for Stages III and IV epithelial ovarian cancer over the period January 2006–December 2018 were identified through a prospectively maintained database. All patients with an IP port inserted were included. A control group of patients treated with IV chemotherapy was created using criteria identified during the study and in the randomised trials that tested IP chemotherapy. Assessments were made for relapse‐free survival (RFS) and overall survival (OS) for each cohort.ResultsA total of 639 patients received adjuvant chemotherapy (73 IP and 566 IV) during the study period. Both the IP group and matched IV control group (65 patients) had a median RFS of 26 months. The median OS in the IP group was 63.9 months, and in the IV group was 57.2 months. At ten years, a significantly higher proportion of patients were alive in the IP group cohort (16% vs 3%, relative risk 5.5, 95% CI 1.29–24, P = 0.012). IP chemotherapy was well tolerated by our cohort. In the IP group, 73% had four or more IP cycles and 99% received six or more cycles of chemotherapy.ConclusionsOur cohort had a high rate of completion of IP chemotherapy with excellent rates of completion of six cycles of any treatment. The RFS and OS in the IP chemotherapy group were comparable to each other and reflected those in the published literature. A significantly higher proportion of patients in the IP cohort were alive at ten years than in the IV cohort.

Concurrent RB1 Loss and BRCA Deficiency Predicts Enhanced Immunologic Response and Long-term Survival in Tubo-ovarian High-grade Serous Carcinoma

Abstract Purpose: The purpose of this study was to evaluate RB1 expression and survival across ovarian carcinoma histotypes and how co-occurrence of BRCA1 or BRCA2 (BRCA) alterations and RB1 loss influences survival in tubo-ovarian high-grade serous carcinoma (HGSC). Experimental Design: RB1 protein expression was classified by immunohistochemistry in ovarian carcinomas of 7,436 patients from the Ovarian Tumor Tissue Analysis consortium. We examined RB1 expression and germline BRCA status in a subset of 1,134 HGSC, and related genotype to overall survival (OS), tumor-infiltrating CD8+ lymphocytes, and transcriptomic subtypes. Using CRISPR-Cas9, we deleted RB1 in HGSC cells with and without BRCA1 alterations to model co-loss with treatment response. We performed whole-genome and transcriptome data analyses on 126 patients with primary HGSC to characterize tumors with concurrent BRCA deficiency and RB1 loss. Results: RB1 loss was associated with longer OS in HGSC but with poorer prognosis in endometrioid ovarian carcinoma. Patients with HGSC harboring both RB1 loss and pathogenic germline BRCA variants had superior OS compared with patients with either alteration alone, and their median OS was three times longer than those without pathogenic BRCA variants and retained RB1 expression (9.3 vs. 3.1 years). Enhanced sensitivity to cisplatin and paclitaxel was seen in BRCA1-altered cells with RB1 knockout. Combined RB1 loss and BRCA deficiency correlated with transcriptional markers of enhanced IFN response, cell-cycle deregulation, and reduced epithelial–mesenchymal transition. CD8+ lymphocytes were most prevalent in BRCA-deficient HGSC with co-loss of RB1. Conclusions: Co-occurrence of RB1 loss and BRCA deficiency was associated with exceptionally long survival in patients with HGSC, potentially due to better treatment response and immune stimulation.