Cowden Syndrome: A Rare Cause of Intestinal Polyposis

Cowden syndrome (CS) is a rare autosomal dominant genodermatosis disorder. This disease is characterized by the development of several hamartomata lesions in a variety of tissues from all three embryonic layers. The most well-known hamartomata are those of the gastrointestinal system, which represent one of the major criteria for the diagnosis of CS. Yet, the most frequent initial presenting symptom of the disease is thought to be mucocutaneous symptoms such as trichilemmomas, acral keratosis, and oral papilloma. Early diagnosis and management are essential to improving the quality of life for patients with CS as this disorder predisposes them to cancers such as thyroid, breast, gastrointestinal, and endometrial cancers. This report presents a rare case of CS in a Bahraini child who presented with macrocephaly and had numerous intestinal polyposis. Genetic testing using whole exome sequencing confirmed the diagnosis, identifying a pathogenic de novo phosphatase and tensin homolog gene (PTEN) variant (Chr10 NM_000314.8: c.17_18del p.(Lys6Argfs*4)) in a heterozygous state. This variant has been confirmed by Sanger sequencing.