Background: Although lymph node and liver metastases are recognized as indications for resection of metastatic disease from colorectal cancer, carcinomatosis has not traditionally been regarded as having surgical treatment options. Reports have suggested that complete surgical removal of carcinomatosis combined with thorough irrigation of the peritoneal cavity with chemotherapy could result in longterm survival in selected patients. Proper selection factors are important because palliative surgery in these patients has not proved beneficial.
Study design: From a database of 156 patients with carcinomatosis from colorectal cancer, a retrospective analysis of data prospectively recorded in 70 patients with complete cytoreduction was performed. Eleven clinical and treatment factors were studied in univariate and multivariable analyses using survival as an end point.
Results: By univariate analysis, patients with peritoneal cancer index (PCI) of<20 had a median survival of 41 months compared with 16 months for patients with PCI>20 (p=0.004). The difference in negative versus positive lymph nodes was also significant; differences in survival that were improved but not significant were present for age greater than 30 years, mucinous histology, location within the colon versus rectum, and absence of an adverse factor such as cancer perforation or obstruction present at the time of primary cancer resection. Only PCI<20 versus PCI>20 and lymph node status were significant in the multivariable analysis.
Conclusions: Favorable longterm results of complete cytoreduction in patients treated for carcinomatosis are associated with a limited volume of carcinomatosis observed at the time of cytoreduction and in patients with negative lymph nodes at the time of primary operation.