Background: DICER1, cancer predisposition syndrome (CPS), seems to escape timely diagnosis in pediatric patients. Case report 1: A 16-year-old female patient was referred to the endocrinology ward due to a large goiter. Her medical history indicated normal sexual maturation, with menarche occurring at 13.5 years. Over the past 2.5 years, she developed pronounced androgenic symptoms, including a deepened male voice, facial, back and neckline acne, hirsutism, and menstrual irregularities leading to secondary amenorrhoea. A thyroid ultrasound identified a multinodular goiter with cystic-solid lesions containing calcifi-cations. An abdominal ultrasound identified a 5.7x6.9 cm solid mass in the right adnexal region, displacing the uterus to the left. Histopathological examination confirmed a Sertoli-Leydig cell tumor. The patient was subjected to total thyroidectomy. Histopathology revealed benign follicular cell-derived neoplasms. Thyroid follicular nodular disease was diagnosed bilaterally. DNA analysis using NGS, confirmed by the Sanger method, revealed a pathogenic heterozygotic variant c.2953>T [p.Gln985*] in exon 18 of DICER1 gene. Case report 2: A 12-year-old male patient was admitted to the pediatric surgery unit due to a 33 ml goiter. A month prior to admission, the patient discovered a palpable nodule in his neck, accompanied by hoarseness. An ultrasound revealed a multinodular goiter. Molecular analysis revealed a pathogenic heterozygotic variant c.2782C>T [p.Gln928Ter] in exon 17 of DICER1 gene. Subsequently, a total thyroidectomy was performed, and histopathological examination revealed thyroid follicular nodu-lar disease bilaterally. Conclusion: Multinodular goiter, although rare in pediatric population, when accompanied by characteristic ultrasound and histopathological features, and by additional features such as androgen excess, warrants exclusion of DICER1 syndrome.

Thyroid hormones have a catabolic effect on bone homeostasis. Hence, this study aimed to evaluate serum vitamin D, calcium, and phosphate and bone marker levels and bone mineral density (BMD) among patients with different thyroid diseases. This cross-sectional study included patients with underlying thyroid diseases (n=64, hyperthyroid; n=53 euthyroid; and n=18, hypothyroid) and healthy controls (n=64). BMD was assessed using z-score and left hip and lumbar bone density (g/cm2). Results showed that the mean serum vitamin D Levels of all groups was low (<50 nmol/L). Thyroid patients had higher serum vitamin D levels than healthy controls. All groups had normal serum calcium and phosphate levels. The bone marker levels were significantly high in the hyperthyroid group and low in the hypothyroid group. The z-score for hip and spine did not significantly differ between thyroid patients and control groups. The hip bone density was remarkably low in the hyperthyroid group. In all groups, the serum vitamin D levels were below the cutoff value. However, thyroid patients had a higher serum vitamin D level than healthy controls. The carboxy terminal collagen crosslink and procollagen type I N-terminal propeptide levels were high in hyperthyroid patients and low in hypothyroid patients. Further, hyperthyroid patients had a low hip BMD.