Endocrine Abstracts

Introduction: Multiple endocrine neoplasia type 2 (MEN2) comprise a group of heritable disorders that result from mutations in the RET proto-oncogene on chromosome 10. MEN2 is sub classified into MEN2A and MEN2B; these syndromes are characterised by the development of tumours at multiple sites. MEN2A is characterised by medullary thyroid cancer, phaeochromocytoma, and primary parathyroid hyperplasia.

Description/case presentation: The index case is a 49 year old female with a recent diagnosis of right phaeochromocytoma on screening for known MEN2A. Her mother had a parathyroidectomy, a partial thyroidectomy and bilateral phaeochromocytoma. The index case had a total thyroidectomy in 1980 at which time C cell hyperplasia was noted. Diagnosis was confirmed by RET oncogene mutation analysis. She has three children who are MEN2A positive and are undergoing screening. Her daughter was diagnosed with a phaeochromocytoma in 2006 with a subsequent unilateral adrenalectomy. There is also a family history of slipped upper femoral epiphysis; she had a unilateral SUFE in her teens prior to her diagnosis of MEN2A. Her daughter underwent surgery for bilateral SUFE at the age of 11 and 12. SUFE is the most common hip disorder affecting the adolescent population; there are believed to be multiple aetiological factors. In the literature, SUFE has been attributed to endocrine pathologies including hypogonadism and panhypopituitarism, deranged parathyroid hormone function and hypothyroidism. Both the index case and daughter were slim and had no history of trauma therefore atypical for SUFE.

Discussion/conclusion: We postulate that changes in parathyroid hormone or fluctuations in T₄ level in response to replacement during adolescence may have contributed to the development of SUFE in this family. Patients with MEN2A may be particularly vulnerable to this disorder because of their young age at the time of endocrine disturbance. This has not been reported previously in the literature.