ESPE Abstracts

Introduction: DICER1 syndrome is a pleotropic, autosomal dominant familial genetic tumor predisposition syndrome. DICER1 somatic + germ-line mutations (double hit hypothesis); cystic nephroma; pleuropulmonerblastoma, ovarian sex cord-stromal tumors, multinodular goitre (MNG) are associated with many conditions such as differentiated thyroid cancer, pituitary blastoma. We presented three cases, two of whom were siblings, who had been consulted because of non-menstruation and goitre and had the same diagnosis despite their different characteristics.

Case 1: A 15-year-old girl presented with menstrual irregularity, hairing increase and neck swelling. In physical and laboratory examination; goitre, muscular appearance in the arms-legs, hirsutism, fat loss in the cheeks, increased fat tissue in the gluteal region, hyperandogenism, insulin resistance, low leptin, MNG, total body MRI revealed signs of partial lipodystrophy Metformin was started. Nodul cytology; follicular neoplasia was suspected due to near totale thyroidectomy. In the follow-up new nodule development in residual tissue and growth in existing nodules are observed. In the first year of follow-up, an increase in hyperandrogenism and an increase in tumor markers and an ovarian mass occurred despite of metformin treatment. After protective ovarian surgery; Sertoli-Leydig cell tumor was diagnosed. Somatic mutation was detected in DICER1 gene. Germ-line mutation examination is still ongoing.

Case 2-3: She was referred to the goiter at the age of seven years and she was operated for multicystic nephroma-neuroblastoma at the age of 14 months. Follicular neoplasia was detected in MNG-nodul cytology. Total thyroidectomy was performed. Somatic + germ-line mutation was detected in DICER1 gene. When the sister of the case was evaluated at the age of six, MNG was detected and in the follow-up; nodules growth, development of new nodules while first cytology was benign; total thyroidectomy was performed due to the detection of unclear atypia in final sampling. Papillary carcinoma suspicion and a germline mutation were detected in DICER1 gene. A somatic mutation examination was planned.

Conclusion: Although DICER1 syndrome is a tumor predisposition syndrome, it can also perform endocrine effects (MNG, differentiated thyroid cancer, ovarian sex cord-stromal tumors, pitutier blastoma-related diabetes insipitus / Cushing's disease. Here previously not reported rare cases with acquired partial lipodystrophy are presented which had similar features of MNG.