Searchable abstracts of presentations at key conferences in endocrinology
Endocrine Abstracts (2019) 63 P421 | DOI: 10.1530/endoabs.63.P421

1Department of Nuclear Medicine and Endocrine Oncology, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Gliwice, Poland; 2The Oncologic and Reconstructive Surgery Clinic, Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch, Gliwice, Poland.

Introduction: Germline mutations of RET oncogene result in development of multiple endocrine neoplasia type 2 (MEN 2). There is a strong correlation between type of the RET sequence changes and the aggressiveness of main syndrome feature, medullary thyroid carcinoma (MTC), and the incidence of remaining manifestations, mainly pheochromocytoma (PHEO). For many of the RET germline mutations, the clinical risk have been precisely defined, but there are still RET sequence changes of unknown significance, among which RET Y791F is the most controversial variant.

Material and methods: We retrospectively studied clinical data of 90 patients (28 index cases and 62 relatives) with RET Y791F variant, registered in our Department. In each patient with diagnosed PHEO additional predisposing genes (VHL, SDHx, TMEM127, MAX) were sequenced.

Results: In a group of index cases, in 5 patients pheochromocytoma (3 benign and 2 malignant with confirmed metastases) and in 23 medullary thyroid cancer were the first clinical manifestation with the mean age of revealing 35.8 years in case of PHEO and 58.6 years in case of MTC. Among 62 screened relatives, mean age 37.7 years, in 12 cases lack of data made determination of clinical status impossible, 50 from 62 relatives remained under close surveillance for mean time of 6 years. During follow up period MTC was diagnosed in 1 patient, 23 patients were subjected to prophylactic total thyroid excision with no MTC and 9 cases of C-cell hyperplasia on histological analysis. 26 patients, mean age 30.6 years, are still being observed with no clinical, biochemical or ultrasonographical symptoms of MTC. In the whole group of screened relatives there were no pheochromocytoma. There were also no coincidence of MTC and PHEO in RET Y791F carriers.

Conclusions: The controversy over the importance of RET Y791F variant, prompted us to retrospective analysis of RET Y791F carriers medical history. Only one casee of MTC revealed in our cohort of screened relatives, occasional pheochromocytoma cases reported in RET Y791F carriers, recent reports from other centers suggesting no causative role of this variant in MEN 2 development, induce the question about surveillance in this group of patients and moreover the legitimacy for prophylactic thyroidectomy in asymptomatic subjects. On the other hand, low mean age of followed up relatives may raise doubts, whether the clinical manifestation will not appear in the later age, typical for low risk RET oncogene mutations.

Volume 63

21st European Congress of Endocrinology

Lyon, France
18 May 2019 - 21 May 2019

European Society of Endocrinology 

Browse other volumes

Article tools

My recent searches

No recent searches.