Endocrine Abstracts

A 27-year-old lady presented with headache, bilateral papilloedema and long standing thyroid enlargement. Her MRI brain showed a cerebellar lesion. She had surgery and histology was consistent with Lhermitte–Duclos, a benign brain tumour. She also had retinal changes. Her fluroscein angiogram and optical coherence tomography showed multiple retinal harmatomas and pigmented retinal epithelium. She had retrosternal thyroid extension and had total thyroidectomy because of tracheal compression. In view of brain histology and goitre, Cowden syndrome was suspected. Genetic analysis confirmed PTEN gene mutation and clinical diagnosis.

Cowden syndrome is a rare autosomal dominant condition characterised by multiple harmatomas affecting multiple organs including endocrine glands, skin and mucous membrane. The condition develops due to a mutation in tumour suppressor gene PTEN on chromosome 10q23. PTEN is responsible for cell growth, apoptosis and cell migration. It has near complete penetrance which becomes evident by age 20 in most affected individuals. There is increased incidence of certain type of malignancies, the commonest being breast (25–50%), non medullary thyroid cancer (10%) and endometrium carcinomas (5–10%).

Surveillance is vital in patients with confirmed PTEN mutation. The difficulty arises as there are variable phenotypes and age-related penetrance. Based on NCCN recommendation (2009), a protocol for screening and surveillance of Cowden syndrome has now been developed by St George’s Genetic Department.