Progression following neoadjuvant systemic chemotherapy may not be a contraindication to a curative approach for colorectal carcinomatosis.

OBJECTIVE: The objective of this retrospective study was to evaluate the influence of neoadjuvant systemic chemotherapy on patients with colorectal carcinomatosis before a curative procedure.
BACKGROUND: Peritoneal carcinomatosis (PC) from colorectal cancer may be treated with a curative intent by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). The role of perioperative systemic chemotherapy for this particular metastatic disease remains unclear.
METHODS: One hundred twenty patients with PC from colorectal cancer were consecutively treated by 131 procedures combining CRS with HIPEC. The response to neoadjuvant systemic chemotherapy was assessed on data from previous explorative surgery and/or radiological imaging.
RESULTS: Ninety patients (75%) were treated with neoadjuvant systemic chemotherapy in whom 32 (36%) were considered to have responded, 19 (21%) had stable disease, and 19 (21%) developed diseases progression. Response could not be evaluated in 20 patients (22%). On univariate analysis, the use of neoadjuvant systemic chemotherapy had a significant positive prognostic influence (P = 0.042). On multivariate analysis, the completeness of CRS and the use of adjuvant systemic chemotherapy were the only significant prognostic factors (P < 0.001 and P = 0.049, respectively). Response to neoadjuvant systemic chemotherapy had no significant prognostic impact with median survival of 31.4 months in patients showing disease progression.
CONCLUSIONS: In patients with PC from colorectal cancer without extraperitoneal metastases, failure of neoadjuvant systemic chemotherapy should not constitute an absolute contraindication to a curative procedure combining CRS and HIPEC.