RESUMEN
Cowden syndrome is an inherited disease characterized by mucocutaneous lesions, gastrointestinal hamartomatous polyposis and an increased risk of breast, thyroid and endometrial carcinomas. Despite well described phenotypic expression of this disease, it is not easy to determine correct clinical diagnosis. In this case report we present a clinical history of a patient with Cowden syndrome. When he was 22 years old, he was found to have polyposis of gastrointestinal tract. The diagnosis of Peutz-Jeghers syndrome was established. Owing to intensive belly spasms, as a 36-year-old he was sent to another gastroenterological department where the thorough gastrointestinal tract examination was performed. We found glycogenic acanthosis of the esophagus; diffuse polyposis with large polyps within the stomach, and polyposis with small polyps in duodenum, colon, and rectum. We also noted the presence of excessive mucocutaneous papillomatosis of the lips and subtle skin lesions. Possible Cowden syndrome diagnosis was suggested. The same year he underwent plastic operation of the lips. During surgery, diffuse nodularity of the trachea was also noted. After plastic operation and assessment of Cowden syndrome as a possible diagnosis, he was recommended for a genetic examination. Diagnosis of Cowden syndrome was confirmed by sequencing analysis of the PTEN gene (phosphatase and tensin homolog deleted on chromosome 10). We found 'c.825_840delAAATACATTCTTCATA' deletion. This case affirmed that, for establishment of a correct diagnosis, especially for rare clinically overlapping syndromes, molecular testing is usually the only reliable method.