SERIAL SURGERY IN A FAMILY NEWLY DETECTED WITH RET MUTATION AT CODON 634, EXON 11 (NM020975.6:c.1901G>T,NP_066124.1:p.Cys634Phe)

Abstract

Prompt thyroidectomy and lymph nodes resection represents the only method of therapy in medullary thyroid cancer (MTC) with curative potential. This aspect is related to family members who are already known with a RET mutation or to accidentally detected nodules at thyroid ultrasound which turned out to be calcitonin - producing malignant tumors. We aim to introduce a family diagnosed with familial MTC (FMTC) starting from an incidental detection of a thyroid nodule in index – case, followed by multiple thyroidectomies in the other members of the family caring the same mutation. The proband is a 26-year-old female who was admitted for suspicion of MTC which was post-operatory confirmed. She was identified as caring RET gene mutation at codon 634, exon 11 (NM020975.6:c.1901G>T,NP_066124.1:p.Cys634Phe). Her grandmother had died two decades ago of an aggressive form of MTC, but not further investigations were done within the family. The only sister of the proband, a 29-year-old female was assessed and confirmed with RET- related MTC but also with post-operative confirmation of a upper left parathyroid adenoma (which was pre-operatory suspected due to mild primary hyperparathyroidism). Their mother, despite having a hemi-thyroidectomy done 2 decades prior (and considered a benign goiter), was re-assessed and total thyroidectomy was performed with MTC confirmation. The four grandchildren were tested, and only the two children of the index-case were RET-positive. Prophylactic thyroidectomy is recommended before the age of 5 according to 634 codon mutation. Genetic assessment is extremely useful in familial syndromes in order to provide lifesaving prophylactic removal of thyroid.