[Thyroid cancer in a child with Cowden syndrome].

Cowden disease (Cowden syndrome) refers to PTEN-associated hamartoma tumor syndromes. It arises due to a mutation in the phosphatase and tensin homolog gene, one of the main functions of which is cell cycle regulation. The presence of a mutation in the gene leads to uncontrolled cell growth, and patients have a lifelong increased risk of neoplasms of various degrees of malignancy. This article presents a clinical case of Cowden syndrome with an early debut at the age of 7 years. The combination of macrocephaly (SDS of head circumference >2) with various skin manifestations (facial trichilemmomas, acral keratosis, papillomatous papules) and the presence of benign and/or malignant neoplasms are pathognomonic for Cowden syndrome. Of the malignancies, breast and thyroid cancer, colorectal cancer, renal cell carcinoma, and endometrial cancer are the most common. Thyroid carcinoma has been shown to have an earlier age of manifestation and often occurs already in childhood. This determines the need to screen patients with a proven mutation in the PTEN gene for nodal neoplasms from an early age. If surgical treatment is necessary, thyroidectomy remains preferable due to the frequent recurrence of nodules, as well as the uncertain potential for malignancy due to the low study of thyroid nodules in patients with mutations in the PTEN gene.