Histology of familial thyroid tumours linked to a gene mapping to chromosome 19p13.2

zThis paper describes the pathology of thyroid tumours showing an autosomal mode of inheritance linked to a gene that maps to chromosome 19p13.2. All the affected members from the family (seven males and two females; mean age 23 years) were clinically euthyroid and presented with nodular goitre; tum our recurrence after thyroidectomy was observed in four. In four of the fiv e patients studied, the tumours were multifocal, bilateral well demarcated or encapsulated and composed of follicles, papillae, trabeculae/solid areas (often resembling hyalinizing trabecular adenoma of the thyroid) or an adm ixture, formed by cells with pale to intense cytoplasmic eosinophilia. A di agnosis of multiple adenomatous goitre was made in the thyroidectomy specim en from two patients, while the other two patients showed, in addition to m ultiple adenomas, a co-existent oxyphil papillary carcinoma. The fifth pati ent had an oxyphil cell carcinoma. All tumours were of follicular cell orig in as shown by immunocytochemistry. Less than a third of the benign tumours and all three carcinomas showed a variable number of neoplastic cells diff usely immunostained for mitochondria. Histological findings of a 'multiple adenomatous goitre', non-endemic 'multinodular goitre' or multiple neoplasm s of follicular cell origin with the morphology of those described here, pa rticularly in young patients, should alert the pathologist and physician to the possibility of an inherited trait, with its implications for family sc reening. The tumours are usually benign and well demarcated but because of multicentricity and consequently increased risk of recurrence and/or progre ssion to carcinoma, total thyroidectomy should be advocated. Copyright (C) 1999 John Wiley & Sons.