IMPE Abstracts

Dicer one mutation syndrome is a familial tumour predisposition entity caused by mutations on Dicer 1, an important component of the micro-RNA processing pathway. Clinical manifestations include pleuropulmonary blastoma, anaplastic renal sarcoma, Wilms tumour, Sertoli Leydig cell tumour, differentiated thyroid carcinoma, ciliary body medulloepitelioma, embryonal rhabdomyosarcoma and primary brain tumours. We describe a case of a nine-year-old boy seen in the endocrinology clinic for a thyroid nodule. A neck mass was discovered in a routine evaluation in the haematology department where the boy was controlled for a chronic thrombocytopenic idiopathic purpura. He has 4 sisters: the oldest one had, when she was 13 years old, a papillary thyroid cancer without nodular invasion was diagnosed, total thyroidectomy was done and 100 mcui radioiodine was given. She developed severe virilization at 15 years, an ovarian malignant stromal and indeterminate sex cord malignant tumour without capsular invasion was diagnosed, she was operated and received chemotherapy. Afterwards she developed lymphatic leukaemia and died. The second sister was seen in the endocrinology department with signs of virilization: voice changes, beard appearance, acne, clitoromegaly, an ovarian Sertoli Leydig cell tumour was diagnosed at 15 years. Thyroid us was made finding a big vascularized isoechogenic nodule in the left thyroid lobule with some anecogenic areas measuring 3.8 * 2.5 * 2.2 cm in diameter needing surgery. Ovarian and thyroid surgery was performed showing mixed stromal-sexual cord Sertoli Leydig cell tumour. In the thyroid follicular hyperplasia was found. The youngest sister now 6 years 9 months old and is being followed as if she has the mutation. He has another big sister, but no data is available. His mother was operated due to a massive goitre and the father has a thyroid nodule that was also operated, no malignancy was found. The index patient had a thyroid nodule that measures 2 cm with moderate vascularization. Surgery was done showing a papillary thyroid cancer, follicular variant, multifocal, touching the capsule without infiltration. He received 50 mcui of radioiodine. He has evolved with hypoparathyroidism and without relapses. In this context genetic study was done finding a Dicer 1 likely Pathogenic variant, c.5096-2A>T (Splice acceptor). This mutation has not been described in the literature. This case reflects the importance of suspecting familial predisposition tumour syndromes so to proceed early in the evaluation of the rest of the family members that can be compromised