During an 18-year period, 2600 patients were treated for colorectal carcinoma in the Montpellier Cancer Institute. Of the 93 patients younger than 40 years of age (3.6%), 78 records were retrospectively studied. The overall 5-year survival rate was 30%. Their survival was not significantly affected by the site of the primary tumor, the degree of tumor differentiation, or sex. The only significant parameter was Dukes' staging at presentation (P less than 0.0001). An analysis of sites of recurrence revealed the frequency of liver metastasis, ovarian metastasis in women, and local recurrence of rectal cancer. Although the high failure rate in these areas clearly justifies aggressive combined therapy, the high frequency of inaugural Stage D patients (27%) and their short mean survival time (5 months), underline the crucial importance of early detection. However, it is unfortunate that colorectal cancer screening in young patients is difficult because of the low rates of precancerous states (4%).