Should Cytoreductive Surgery Alone for Peritoneal Metastases of Colorectal Origin be Centralized? A National Study of 4159 Procedures.

BACKGROUND

Addition of oxaliplatin-based hyperthermic intraperitoneal chemotherapy (HIPEC) to cytoreductive surgery (CRS) in the treatment of peritoneal metastases of colorectal origin (CRPM) did not show any survival benefit in the PRODIGE 7 trial (P7). This study aimed to investigate whether perioperative outcomes after CRS alone for CRPM patients is mediated by hospital volume and to determine the effect of P7 on French practice for CRPM patients treated respectively with CRS alone and CRS/HIPEC.

METHODS

Data from CRPM patients treated with CRS alone between 2013 and 2020 in France were collected through a national medical database. The study used a cutoff value of the annual CRS-alone caseload affecting the 90-day postoperative mortality (POM) determined from our previous study to define low-volume (LV) HIPEC and high-volume (HV) HIPEC centers. Perioperative outcomes were compared between no-HIPEC, LV-HIPEC, and HV-HIPEC centers. The trend between years and HIPEC rates was analyzed using the Cochrane-Armitage test.

RESULTS

Data from 4159 procedures were analyzed. The patients treated in no-HIPEC and LV-HIPEC centers were older compared with HV-HIPEC centers (p < 0.0001) and had a higher Elixhauser comorbidity index (p < 0.0001) and less complex surgery (p < 0.0001). Whereas the major morbidity (MM) rate did not differ between groups (p = 0.79), the 90-day POM was lower in HV-HIPEC centers than in no-HIPEC and LV-HIPEC centers (5.4% vs 15% and 13.3%; p < 0.0001), with lower failure-to-rescue (FTR) (p < 0.0001). After P7, the CRS/HIPEC rate decreased drastically in Cancer centers (p < 0.001), whereas patients treated with CRS alone are still referred to expert centers.

CONCLUSIONS

Centralization of CRS alone should improve patient selection as well as FTR and POM. After P7, CRS/HIPEC decreased mostly in Cancer centers, without any impact on the number of CRS-alone cases referred to expert centers.