Endocrine Abstracts

Introduction: Thyroid cancers are the most common endocrine cancer among children, accounting for 0.5–3% of all childhood malignancies. Thyroid carcinogenesis is well established in Multiple Endocrine Neoplasia syndromes type 2, and may present with medullary thyroid cancer at young age. However, with the advancement of genetics, several other syndromes need to be considered which may lead to non-medullary thyroid cancers including DICER1 tumour predisposition syndrome, PTEN hamartoma tumour syndrome (PHTS), familial adenomatous polyposis (FAP), Carney complex and, Werner which may now be part of the differential diagnosis in a child with a thyroid mass.

Case presentation: A nine and half year old previously well girl, while accidentally palpating the neck was found to have a small, hard lump. It was not painful, no compressive symptoms, with no recent enlargement. She was clinically euthyroid and systemic inquiry was negative. A strong family history for various cancer types were noted among both maternal and paternal sides, namely ovarian, bladder, bowel cancer and Hodgkin’s lymphoma, but no history of thyroid cancer. On examination there was a raised fixed non tender firm lump on right anterior neck with no lymphadenopathy. USS neck revealed 20×22 mm solid nodule in right lobe of thyroid gland with well-defined lobulated margins. Fine needle aspiration was keeping with papillary thyroid cancer (PTC). She underwent uneventful total thyroidectomy, with confirmation of PTC on histology. In view of the strong family history of different types of cancer, the possibility of DICER 1 was raised.

Discussion: DICER1 syndrome is an autosomal dominantly inherited cancer predisposing syndrome, leading to a variety of neoplastic and dysplastic lesions. Pleuropulmonary blastoma is a well-recognised, fairly specific feature detected mainly in children under 6 years of age. Other clinical presentations may include ovarian Sertoli–Leydig cell tumour (SLCT), multinodular goitre, differentiated thyroid carcinoma, pineoblastoma, and sarcomas of different sites. Due to wide phenotype and variation in presentation, the possibility of a DICER-1 mutation can often be overlooked. It is important to identify affected individuals to plan follow up and screening, and to identify other affected family members although, the overall tumour penetrance of the condition is relatively low.