Delivering adjuvant HIPEC to patients with T4 or perforated colon cancer provides no improvement in peritoneal metastasis-free survival (PMFS) when added before standard systemic therapy, according to results of the randomized phase III COLOPEC trial.

In the intention-to-treat analysis, 18-month PMFS—the primary endpoint—was 81% with oxaliplatin-based HIPEC followed by adjuvant FOLFOX or CAPOX versus 77% with adjuvant systemic chemotherapy alone (HR 0.836, 95% CI [0.489, 1.428]).

Similar results were observed for other efficacy endpoints. Comparisons of HIPEC followed by adjuvant chemotherapy and adjuvant chemotherapy alone revealed no differences in 18-month disease-free survival (HR 1.016, 95% CI [0.646, 1.598]) or 18-month overall survival (HR 1.139, 95% CI [0.532, 2.439]). Moreover, one patient who received adjuvant HIPEC developed encapsulating peritoneal sclerosis.

A total of 204 adult patients with T4 or perforated colon cancer who underwent curative resection were enrolled in the trial. The vast majority of participants in the experimental arm received adjuvant HIPEC through laparoscopy or laparotomy 5 to 8 weeks after primary tumor resection (91%), whereas the remainder (9%) received HPIEC at the time of initial surgery. Standard adjuvant chemotherapy was to be given within 3 weeks from HIPEC administration. In accord, the control arm received adjuvant chemotherapy a median of 6 weeks following tumor resection, whereas the median was 10 weeks for the experimental arm.

All patients without evidence of disease recurrence at 18 months based on carcinoembryonic antigen testing and CT imaging underwent diagnostic laparoscopy to confirm the absence of peritoneal carcinomatosis. The study is ongoing to capture more mature survival data.

This article is news of a study presented at the 2019 Gastrointestinal Cancers Symposium. Read the original here.