The Significance of Peritoneal Effusion in Colorectal Cancer

Lee, In Kyu; Yi, Jeong Min; Lee, Yoon Suk; Kim, Hyung Jin; Park, Jong Kyung; Oh, Seong Taek; Kim, Jun Gi; Jeon, Hae Myung; Chang, Suk Kyun

Abstract

PURPOSE
It has been reported that in colorectal cancer, the positive rate of the cytological examination of ascites is low and that the cytologically positive result of the cancer cell influences its prognosis; nonetheless, not many studies on the correlation of the formation of peritoneal effusion and cancer have been done yet. Thus, this study on the correlation of clinico-pathological findings with peritoneal effusion was initiated.
METHODS
The study population, includes a total of 191 patients who underwent an operation for colon cancer and rectal cancer from May 1, 2004, to December 31, 2005. Peritoneal effusion considered to be present in cases with more than 10 cc of body fluid retained in the Douglas pouch, and a cytological test was performed on patients whose retained fluid was more than 50 cc. In all patients, the correlation of the clinico-pathological findings with peritoneal effusion was analyzed, and the volume of effusion and the positive result of peritoneal cytology were compared.
RESULTS
Among the 191 patients, patients without peritoneal effusion numbered 133 (69.6%) and patients with peritoneal effusion numbered 58 (30.4%). Between the two groups, the presence of intestinal obstruction due to cancer (P<0.001), perineural involvement (P=0.025), lymph node metastasis (P=0.004), lymph-node stage (P=0.001), distal metastasis (P=0.012), macroscopic peritoneal dissemination, and stage (P=0.017) were statistically significantly different. In the multivariate analysis, only the presence of intestinal obstruction and lymph-node disease stage correlated statistically significantly to the formation of peritoneal effusion (P=0.009, 0.004). Twenty patients (34.5%) had peritoneal effusion of more than 50 cc, and among them, malignant cells were detected in 3 patients (15%). Based on 50-cc peritoneal effusion, more or less effusion and the detection of malignant cells by peritoneal cytology did not correlate with the clinico- pathological outcomes (P>0.05).
CONCLUSIONS
For colorectal cancer patients with peritoneal effusion, but without co-morbid medical diseases inducing such peritoneal effusion, by regarding peritoneal effusion itself as meaningful, the range of lymphadenectomies, adjuvant chemotherapy, and other additional therapy should be considered.