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Colorectal cancer obstruction: a challenge to improve prognosis.

Probable factors contributing to the prognosis in 91 colorectal cancer obstructions operated on as emergencies were compared with 555 nonobstructive patients undergoing elective surgery in the same period, 1966-1975. The obstructive patients were older than the elective ones, with a statistically significant difference in the age range 80 years and older. Obstructive lesions were mainly located in the left hemicolon (56%). Although the sigmoid was the most frequent site, only lesions at the splenic flexure occurred more frequently than in patients without obstruction. Lesions in the right hemicolon were predominant in obstructive patients younger than 50 years. The overall 5-year survival for patients with obstructions was 21% but only 8% in those younger than 50 years. The corresponding figures for elective patients were 44% and 53%, respectively. The poorer overall prognosis in the obstruction group was mainly due to a higher postoperative mortality (15.4% vs. 4.7%) and a higher incidence of advanced cancer (stage C + D; 67% vs. 50%). Advanced disease was especially predominant in patients below the age of 50 years. However, this group had no operative mortality. A one-stage operation was performed only for obstructive lesions in the right hemicolon where it was the main (54%) procedure. Obstruction due to cancer in the left hemicolon were managed by Hartmann's procedure and a staged operation with almost equal frequency in 80% of the patients. Crude survival figures favour the staged operation. Obstructive lesions in the left hemicolon had a considerably better 5-year survival than those in the right hemicolon (29% vs. 15%), whereas none of those with rectal obstruction survived for 5 years.(ABSTRACT TRUNCATED AT 250 WORDS)