Perioperative outcomes and platinum resistant recurrence in patients undergoing protocol based total parietal peritonectomy during interval cytoreductive surgery for advanced ovarian cancer- results of the TORPEDO study

Background and aim The TORPEDO (CTRI/2018/12/016789) is the single-arm, prospective, interventional study evaluating the role of a total parietal peritonectomy (TPP) in patients undergoing interval cytoreductive surgery (iCRS). In this manuscript, we report the perioperative outcomes and platinum resistant recurrence (PRR) in 218 patients enrolled in the study. Methods A TPP was performed in all patients undergoing iCRS irrespective of the residual disease extent. HIPEC was performed as per the clinician’s discretion with 75mg/m2 of Cisplatin. Maintenance therapy was also used at the discretion of the treating clinicians. Results From 9th December 2018 to 31st July 2022 (recruitment complete), 218 patients were enrolled at 4 Indian centres. The median surgical PCI was 14 and a complete gross resection was achieved in 95.8%. HIPEC was performed in 130 (59.6%) patients. The 90-day major morbidity was 17.4% and 2.7% patients died within 90 days of surgery. Adjuvant chemotherapy was delayed beyond 6 weeks in 7.3%. At a median follow-up of 19m [95% CI 15-35m], 101 (46.3%) recurrences and 19 (8.7%) deaths had occurred. The median PFS was 22m [95% CI 17-35m] and the median OS not reached. Platinum resistant recurrence was observed in 6.4%. The projected 3-year OS was 81.5% and in 80 patients treated before may 2020, it was 77.5%. Conclusions The morbidity and mortality of TPP with or without HIPEC performed during iCRS is acceptable. The incidence was of PRR is low. Early survival results are encouraging and warrant conduction of a randomized controlled trial comparing TPP with conventional surgery. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial CTRI/2018/12/016789 This study is registered with the clinical trials registry of India ### Clinical Protocols ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Zydus Hospital Ethics Committee approved this study on 8th December 2018 Address: Zydus hospital, Zydus hospital road, Ahmedabad, 380054, India I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data will be made available upon reasonable request to the corresponding author