An incidental finding of pheochromocytoma in a 33-year-old patient with Lynch syndrome.

Pheochromocytoma is a catecholamine-producing neuroendocrine tumor arising from chromaffin cells of the adrenal medulla. The detection of these tumors is extremely important because they are associated with high cardiovascular morbidity and mortality. Progress in molecular genetics has revealed that up to 35% of pheochromocytomas are inhereted. Lynch syndrome (hereditary nonpolypous colorectal cancer - HNPCC) is an autosomal dominant genetic condition that is associated with a high risk of colorectal cancer or other extracolonic tumors (adenocarcinoma of endometrium, stomach, ovarian carcinoma, carcinoma of urinary tract, small intestine, brain tumors and skin cancer). Foreign medical journals are reporting an increasing number of cases on coexistence of HNPCC and neuroendocrine tumors, including pheochromocytoma. It increases the likelihood that this type of tumor could represent an additional extracolonic manifestation of Lynch syndrome.