Giorgio Giorda

Hyperthermic Intraperitoneal Chemotherapy in Platinum-Sensitive Recurrent Ovarian Cancer: A Randomized Trial on Survival Evaluation (HORSE; MITO-18)

PURPOSE To investigate whether the addition of hyperthermic intraperitoneal chemotherapy (HIPEC) to secondary cytoreductive surgery (SCS) without neoadjuvant chemotherapy has a benefit on progression-free survival (PFS), as opposed to SCS alone in patients with platinum-sensitive recurrent epithelial ovarian cancer (platinum-free interval, >6 months). METHODS This was a multicenter randomized phase III study. Random assignment was performed at the time of surgery in cases with residual tumor ≤0.25 cm. HIPEC with cisplatin (CDDP) 75 mg/m 2 for 60 minutes at 41.5°C was administered at the end of surgery in the experimental arm. Both groups received postoperative platinum-based chemotherapy. The primary end point was PFS. The safety profile and postrecurrence survival (PRS) were the secondary end points. RESULTS A total of 167 patients underwent random assignment, 82 patients to SCS plus HIPEC (experimental arm) and 85 to SCS alone (control arm). The median follow-up was 83 months (IQR, 64-102). The median PFS was 23 months (95% CI, 17 to 29) in the group that underwent surgery alone and 25 months (95% CI, 18 to 32) in the group that underwent cytoreductive surgery with HIPEC. The probability of PRS at 5 years was 61.6% (95% CI, 50.8 to 72.4) in the SCS group and 75.9% (95% CI, 66.5 to 85.3) in the SCS plus HIPEC group. The incidence of postoperative adverse events of any grade was similar between the two groups. CONCLUSION The addition of HIPEC to complete or nearly complete primary SCS did not confer a benefit in terms of PFS in patients with platinum-sensitive peritoneal recurrence.

USP1 deubiquitinates PARP1 to regulate its trapping and PARylation activity

PARP inhibitors (PARPi) represent a game-changing treatment for patients with ovarian cancer with tumors deficient for the homologous recombination (HR) pathway treated with platinum (Pt)–based therapy. PARPi exert their cytotoxic effect by both trapping PARP1 on the damaged DNA and by restraining its enzymatic activity (PARylation). How PARP1 is recruited and trapped at the DNA damage sites and how resistance to PARPi could be overcome are still matters of investigation. Here, we described PARP1 as a substrate of the deubiquitinase USP1. At molecular level, USP1 binds PARP1 to remove its K63-linked polyubiquitination and controls PARP1 chromatin trapping and PARylation activity, regulating sensitivity to PARPi. In both Pt/PARPi-sensitive and -resistant cells, USP1/PARP1 combined blockade enhances replicative stress, DNA damage, and cell death. Our work dissected the biological interaction between USP1 and PARP1 and recommended this axis as a promising and powerful therapeutic choice for not only sensitive but also chemoresistant patients with ovarian cancer irrespective of their HR status.

Hyperthermic Intra-peritoneal Chemotherapy (HIPEC) in Ovarian Cancer Recurrence

The purpose of this study is to determine the role of surgery followed by hyperthermic intra-peritoneal chemotherapy (HIPEC) versus surgery alone in patients with platinum-sensitive first recurrence of ovarian cancer. Moreover it is a prospective randomized multicenter trial, aimed to investigate the prognostic role of surgery plus HIPEC versus surgery alone in terms of progression free interval, overall survival, morbidity and mortality, second recurrence pattern, quality of life with EORTC QLQ-C30 and QLQ OV28 questionnaires.