RESUMO
Colonic carcinoma is a well-defined tumor with a low frequency among young people. We report the case of a 34 year old patient having two synchronous colorectal carcinomas of the right colon, who also had a family history of colonic and extracolonic neoplasms. We performed an extended right colectomy without chemotherapy. Fourteen months after surgery he had tumor recurrence and liver metastases. We reviewed then the clinical features, inclusion criteria, screening and the discussed treatment of the hereditary non-poliposis colorectal cancer or Lynch Syndrome, limited to the colon or associated to extracolonic carcinoma (Lynch I and II). A clear and detailed familial history is the only definite criteria for the diagnosis. We recommend early colonoscopy follow-up on first degree relatives considered as a high risk population.