A rare, invasive, and challenging cancer in childhood: diffuse sclerosing variant of papillary thyroid carcinoma
TL;DR
The findings suggest that DSV-PTC can behave aggressively in pediatric patients and can mimic benign inflammatory conditions, leading to potential diagnostic delays, appear vital for managing this challenging variant.
Abstract
Abstract Objectives Pediatric thyroid cancers are rare, with papillary thyroid carcinoma (PTC) being the most common type. The diffuse sclerosing variant (DSV) is a rarer subtype associated with frequent recurrence and extensive lymphatic involvement. Among 51 pediatric patients treated for thyroid carcinoma at our tertiary center over a 20-year period, three were diagnosed with DSV-PTC. We present this retrospective case series to highlight its clinical course and diagnostic challenges. Case presentation Three patients (aged 8–17) presented with neck swelling; one also exhibited high fever and neck pain. While thyroid function tests were normal, serum thyroglobulin levels were significantly elevated. Imaging revealed diverse presentations: a solitary nodule, diffuse enlargement mimicking an abscess, and diffuse inflammation. Following fine-needle aspiration confirmation of PTC, all patients underwent total thyroidectomy and central and bilateral lymph node dissection. Histopathology confirmed DSV-PTC in all cases. Every patient presented with diffuse lymph node metastasis; two showed extrathyroidal extension, and one had distant pulmonary metastasis. Genetic analysis identified a BRAF V600E alteration in one case and RET translocations in the other two, confirmed by fluorescence in situ hybridization (FISH) after negative broad next-generation sequencing (NGS) panels. All patients required revision surgery for residual tissue followed by radioactive iodine (RAI) therapy. At follow-up (13–28 months), outcomes ranged from stable disease and additional RAI requirement to complete remission without relapse. Conclusions Although based on a small case series, our findings suggest that DSV-PTC can behave aggressively in pediatric patients and can mimic benign inflammatory conditions, leading to potential diagnostic delays. Early recognition and a comprehensive multimodal approach, including extensive surgery and RAI, appear vital for managing this challenging variant.