An early diagnosis in asymptomatic patients and a prompt treatment lead to an improved survival rate in patients with carcinoma of the colon. Patients with a short symptomatic history of colon cancer do not have a better prognosis than patients with a long history. Between 1978 and 1984 a consecutive series of 571 patients with colorectal cancer were admitted to the First Department of Surgery of the University of Rome. All patients were classified into five groups according to the duration of specific intestinal symptoms. In Group 1 (51 cases) asymptomatic patients were included, or patients with no specific symptoms such as asthenia, anemia, occult fecal blood. In Group 2 there were 129 patients with intestinal symptoms of less than 3 months' duration before treatment. In Group 3 there were 192 patients with symptoms of between 4 and 6 months' duration; 151 patients with symptoms of between 6 and 12 months were included in Group 4, and finally 48 patients who presented with symptoms of more than 1 year were included in Group 5. No relationship was noted between tumor site and duration of symptoms. Similarly, no relationship was noted between the duration of intestinal symptoms and stage and tumor differentiation. On the other hand, asymptomatic patients showed a higher incidence of T1N0M0 stage tumor and a lower percentage of undifferentiated neoplasms. The resectability rate was 79% and it was significantly related to the absence of intestinal symptoms. Follow-up data were available in 454 patients (80%). The overall survival rate was 52.4%. In Group 1 through Group 5 the 5-year survival rate was: 83.7%, 50%, 50%, 46.3%, 46.9%. The results of our study indicate that patients admitted in asymptomatic phase presented less-advanced stage tumors and, thus, best survival rate. On the other hand, from our data the duration of intestinal symptoms is not related to the stage and prognosis of tumors.