Muir-Torre syndrome is a relatively rare cutaneous manifestation of hereditary nonpolypous colorectal cancer (HNPCC). This autosomal dominant syndrome is characterized by a combination of sebaceous gland and malignant visceral tumors. The common sites of internal malignancies are the gastrointestinal tract and urinary system. It appears in early adult life and its clinical course is relatively slow. In some families genetic diagnosis can identify asymptomatic carriers of the mutation. All first-degree relatives, especially mutation carriers, should be referred from the age of 20 years for routine follow-up and early treatment, as it has been proven to decrease morbidity and mortality. We present a 51-year-old man with Muir-Torre syndrome diagnosed by the presence of multiple adenomas of sebaceous glands, colonic adenoma and adenocarcinoma of the duodenum. The family history was typical for HNPCC. A mutation in the hMSH2 gene on chromosome 2p was found in the patient and in several asymptomatic family members. The aim of this report is to increase awareness of this syndrome and emphasize the importance of referring patients and their families for clinical and genetic counseling and diagnosis.