Referral pathways and outcome of patients with colorectal peritoneal metastasis (CRPM)

INTRODUCTION: Traditionally patients with colorectal peritoneal metastases (CRPM) were offered palliative chemotherapy and best supportive care. With the introduction of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), patients in the UK have been referred to nationally approved centres. This study describes the pattern of referral and outcomes of patients managed through one UK centre.

METHODS: and Methods: A prospective register recorded referrals, demographics, prior treatment pathways, and specialist multidisciplinary team (MDT) decisions (2002-2015). Peritoneal cancer index (PCI) was recorded intra-operatively; complete cytoreduction was deemed when a CC0/1 was achieved. Complications were classified using NCI CTCAE. v.4. Median overall survivals (OS) were described for those treated by CRS/HIPEC and in derived estimates for patients with isolated peritoneal metastases treated by chemotherapy alone in the ARCAD trials consortium.

RESULTS: Two-hundred-eighty-six patients with CRPM were referred. Despite increasing numbers of referrals annually, the proportion of patients selected for CRS/HIPEC decreased from 64.5%, to 40%, and to 37.1% for 2002-09, 2010-12, and 2013-15, respectively (p < 0.017). CRS/HIPEC was undertaken in 117 patients with a median PCI of 7 and CC0/1 achieved in 86.3%. NCI CTCAE grade 3/4 complication rates were 9.4%; 30-day mortality was 0.85%. Median OS following CRS/HIPEC was 46.0 months: that for patients not receiving CRS/HIPEC was 13.2 months.

CONCLUSION: The evolution of the national peritoneal treatment centre over 14 years has been associated with increased referral numbers, refinement of selection for major surgery, matched with achievements of low complication rates and survival advantages in selected patients compared with traditional non-surgical treatments.