Cowden syndrome, also known as multiple hamartoma and neoplasia syndrome or PTEN (phosphatase tensin homologue) hamartoma syndrome, was first described in 1963. Cowden syndrome has a genetic basis in a novel mutation in the transforming growth factor (TGF)-regulated and epithelial cell-enriched phosphatase (PTEN) tumour suppressor gene located on 10q23.3. It characteristically gives rise to lesions from all three germ layers (ectoderm, endoderm and mesoderm), which commonly affect the skin, mucous membranes, breasts, gastrointestinal tract and thyroid gland. Certain lesions have been shown to undergo malignant change, e.g. adenocarcinomas may arise in the breasts, thyroid and gastrointestinal tract. Other associated conditions such as macrocephaly and kyphoscoliosis have also been reported. The reported case is of a 22-year-old female who presented with gingival overgrowth/hyperplasia. Her medical history revealed that she had previously had a follicular adenoma of the thyroid, angiolipomas affecting the leg and forearm and hydrocephalus as a child. The patient underwent routine hygiene phase therapy for her periodontal condition, and later also underwent gingivectomy. The patient has only recently been diagnosed with Cowden syndrome, which highlights the importance of recognising how apparently unrelated medical conditions may form pieces in the jigsaw puzzles that underpin rare syndromes, and which include oral lesions as manifestations of those syndromes. Long-term review of the oral cavity will be essential in this patient, to monitor potential oral tumour development.
Keywords: Bannayan-Riley-Ruvalcaba syndrome, Cowden syndrome, multiple hamartoma syndrome, PTEN (phosphatase tensin homologue) gene