Introduction: Thyroid nodules are uncommon in the paediatric population, present in 5% of children but 35% of adults. However, up to 25% of paediatric nodules are malignant, compared to 5% in adults. It can be challenging to differentiate malignant nodularity from benign clinically, particularly in the presence of a thyroid disorder. We present two contrasting cases of adolescent girls with solitary thyroid nodules.
Case 1: A 13-year-old girl was referred to paediatric endocrinology with lethargy and headaches, with routine bloods which had uncovered biochemical hyperthyroidism (TSH 0.05 mU/l [0.44.0]; T4 10.5 pmol/l [9.025.0]; T3 elevated). She had a previous history of osteochondritis dissecans and a family history of hypothyroidism. On examination, she was euthyroid and a right-sided nodular goitre was palpable. Conservative management was planned as the patient was asymptomatic. An USS revealed a solitary, well-defined nodule (42×27×18 mm) in the right lobule which was isoechoic, heterogeneous, and contained internal vascularity. Reactive cervical nodes were noted. The nodule was hot on scintigraphy, and FNAC indicated a Hürthle cell carcinoma. A repeat USS demonstrated increased vascularity suggesting the carcinoma was active. She was referred for a right hemi-thyroidectomy five months after she first presented.
Case 2: A previously well 14-year-old girl was referred to paediatrics by her GP with lethargy and constipation. Routine bloods demonstrated biochemical hypothyroidism (TSH: 10.5 mU/l [0.44.0], T4: 8.7 pmol/l [9.025.0]). A microcytic iron-deficiency anaemia was also noted and treated. Further symptoms included weekly panic attacks, frequent headaches and dizziness on exertion. On examination, a neck swelling was noted. Hashimotos thyroiditis was diagnosed and treated with levothyroxine. An USS showed a diffusely enlarged, heterogeneous thyroid gland the thyroid gland with a 15 mm hypoechoic nodule on the right, which was attributed to her Hashimotos thyroiditis. However, a further USS revealed the nodule contained peripheral vascularity, and FNAC was suspicious for follicular carcinoma. A diagnostic thyroid lobectomy found an irregular 17 mm nodule containing a 5 mm area of papillary microcarcinoma.
Discussion: The presentations of these two girls have a number of similarities and differences. While both girls presented with lethargy and a thyroid nodule, the initial diagnoses were distinct opposites. Both nodules were found to be malignant, but neither girl presented any red flag symptoms clinically. US features contrasting in these cases can be ambiguous. The commonalities and differences of these presentations demonstrate that paediatric thyroid nodules must be thoroughly investigated, even in the context of a thyroid disorder.
27 - 29 Sep 2018
European Society for Paediatric Endocrinology