Multiple Endocrine Neoplasia -Quick review card
MULTIPLE ENDOCRINE NEOPLASIA – Syndromes of rare inherited disorders in which more than 1 endocrine glands develop benign or malignant tumours or grow excessively without forming tumors
MEN 1 – autosomal dominant disorder multiple hormone secreting tumours , hormone non-secreting tumours and non-endocrine tumours mutations in the tumour suppressor gene MEN1 which encodes menin menin looses its tumour suppressor function
Principal endocrine glands affected are parathyroids ( primary hyperparathyroidism as the initial presentation in 90 % to 100 % cases ) neuroendocrine tumors of the GEP tract ( GEp-NETs which is gastro-entero-pancreatic neuroendocrine tissues ) adenomas of anterior pituitary
autosomal dominant inheritance tumors of the C cells of the thyroid , of the adrenal medulla and parathyroid glands mutation in the RET protooncogenes on chromosome 10 which codes for the tyrosine kinase receptor clinical manifestation medullary thyroid carcinoma ( MTC ) , pheochromocytoma and in case of MEN2A primary hyperparathyroidism
MEN2 includes following phenotypes MEN 2 A ( subclassified into classical MEn2A , MEN2A with cutaneous lichen amyloidosis , MEN2A with Hirschsprung’s disease , Familial medullary thyroid cancer ) MEN 2 B ( more aggressive form ) Adrenal gland affected 50 % cases , parathyroid in 20 % cases and thyroid almost all the time ( Medullary Thyroid Cancer in 2B develops at an early age -even in infants 3 months old )
Tumor in 2 of the 3 main endocrine tissues Diagnosis is by genetic tests , bloods for hormone levels and imaging
Patients affected by MEN 1 may also develop less common endocrine and non-endocrine tumors as carcinoid tumors of the thymus , bronchus , stomach , adrenocortical tumors , cutaneous tumors , CNS tumors , leiomyomas , lipomas , collagenomas and angiofibromas.
prophylactic surgery total thyroidectomy for medullary thyroid cancer lifelong surveillance genetic counselling / evaluation of relatives at risk hormone replacement
Genetic screening is recommended first degree relatives have a 50 % chance of developing the disease MEN1 has no cure and , tumors may be larger , more aggressive and resistant to treatment MEN2 shows a strong genotype phenotype correlation ( not all mutations confer the same aggressiveness )
REFERENCES
- van Treijen MJC, de Vries LH, Hertog D, et al. Multiple Endocrine Neoplasia Type 2. [Updated 2022 Jan 2]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK481898/
- Eng C. Multiple Endocrine Neoplasia Type 2. 1999 Sep 27 [Updated 2019 Aug 15]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2022. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1257/
- Multiple Endocrine Neoplasia Orphanet: Multiple endocrine neoplasia
- C. Romei, E. Pardi, F. Cetani, R. Elisei, “Genetic and Clinical Features of Multiple Endocrine Neoplasia Types 1 and 2“, Journal of Oncology, vol. 2012, Article ID 705036, 15 pages, 2012. https://doi.org/10.1155/2012/705036
