PURPOSE:This study investigated the value of intense follow‐up compared with no follow‐up after curative surgery of cancer in the colon or rectum.METHODS:One hundred seven patients were randomized to no follow‐up (control group; n=54) or intense follow‐up (follow‐up group; n=53) after surgery and early postoperative colonoscopy. Patients in the follow‐up group were followed at frequent intervals with clinical examination, rigid proctosigmoidoscopy, colonoscopy, computed tomography of the pelvis (in patients operated with abdominoperineal resection), pulmonary x‐ray, liver function tests, and determinations of carcinoembryonic antigen and fecal hemoglobin. Follow‐up ranged from 5.5 to 8.8 years after primary surgery.RESULTS:Tumor recurred in 18 patients (33 percent) in the control group and in 17 patients (32 percent) in the follow‐up group. Reresection with curative intent was performed in three patients in the control group and in five patients (four of whom were asymptomatic) in the follow‐up group. In the follow‐up group two asymptomatic patients with elevated carcinoembryonic antigen levels were disease‐free three and five and one‐half years after reresection and were the only patients apparently cured by reresection. No patient underwent surgery for metastatic disease in the liver or lungs. Symptomatic metachronous carcinoma was detected in one patient (control group) after three years. Five‐year survival rate was 67 percent in the control group and 75 percent in the follow‐up group(P >0.05); the corresponding cancer‐specific survival rates were 71 percent and 78 percent, respectively.CONCLUSION:Intense follow‐up after resection of colorectal cancer did not prolong survival in this study.