Incomplete Cytoreduction of Colorectal Cancer Peritoneal Metastases: Survival Outcomes by a Cytoreduction Score.

Background: The surgical management of peritoneal metastases from colorectal cancer has been a topic of controversial discussion for many decades. Peritonectomy and perioperative intraperitoneal chemotherapy added options for surgical treatment of this condition beyond palliative surgery. The most favorable outcomes are recorded when peritoneal metastases from colorectal cancer can be resected to no visible evidence of disease.

Methods: To determine if any benefit from surgical treatment of patients with colorectal peritoneal metastases can occur from incomplete resection of peritoneal metastases, we studied patients by the completeness of cytoreduction (CC) score. The CC-3 indicated a palliative resection, CC-2 gross residual disease, and CC-1 almost complete cytoreduction but visible residual disease. The impact of clinical-, pathologic-, and treatment-related variables on the survival of the three groups was compared.

Results: Eighty-five patients with long-term follow-up were available for study. The median age was 53 years (range 18-82). There were 60 males (70.6%). Symptomatic patients, those with bowel obstruction, and patients with positive retroperitoneal lymph nodes had significantly reduced survival. The median survival of the CC-3, CC-2, and CC-1 groups were significantly different (p = 0.0027). The 2-year or greater survivals of the three groups were 4.8%, 15.1%, and 38.7%, respectively.

Conclusions: If a near complete cytoreduction combined with hyperthermic intraperitoneal chemotherapy can be performed, short-term survival benefit could be observed.