334 A prospective non-randomized study comparing the outcomes following complete versus selective parietal peritonectomy during CRS+HIPEC for advanced epithelial ovarian cancer

Abstract

Objectives To study the impact of the extent of CRS [complete Debulking (CD), optimal Debulking (OD)<1cm, or suboptimal Debulking (SOD) >1cm residual disease] on progression free (PFS) and overall survival (OS) in advanced EOC, PPC and FTC treated at AUBMC 1998-2018. Methods We retrospectively reviewed all patients with advanced disease who underwent either Primary debulking surgery (PDS) or if they had large tumor burden/multiple comorbidities/poor performance status, they received neoadjuvant chemotherapy and interval debulking surgery (NACT+IDS). ResultsOf 300 patients with EOC/PPC/FTC, 220 had advanced stages (IIIB-IV). 66.4% had CD, 29.7% OD and 2.6% SOD. Results are shown in image 1 and tables 2 and 3. Median survival is expressed in months. In stage IIIC, CD led to a significantly higher PFS compared to OD (image 1) (P-value=0.015). However, this increase in PFS was only seen after IDS (table 2) (P-value in IDS=0.009). Once a CD was reached, There was no statistically significant increase in PFS regardless of timing of CRS (Image 3) (Pvalue=0.775). OS was not affected by extent of CRS (Image 1).

Can HIPEC be used against platinum-resistance and for inducing sensitivity to PARP inhibitors in ovarian cancer?

“…Additionally, 60% of patients with advanced serous papillary peritoneal carcinoma treated with NACT followed by total parietal peritonectomy plus HIPEC showed microscopic disease when no disease was macroscopically evident at surgical exploration [29] . For advanced EOC in general, previous studies have reported 36% of patients with disease on pathological assessment with a normal looking visual assessment by surgeons [30] , whereas a high incidence of pathological residual disease has been observed even after a median of five cycles of neoadjuvant chemotherapy was used before interval debulking surgery [31] . In these settings, HIPEC also proved to have a role for EOC based on data of the OV-HIPEC trial by van Driel et al [4] , especially due to the higher risk of developing platinum resistance after NACT [32] .…”