Calvarial metastasis of follicular thyroid carcinoma presenting as a scalp swelling: An unusual clinical challenge

ABSTRACT Differentiated thyroid cancers include papillary and follicular types that arise from the follicular epithelium. Follicular thyroid carcinoma (FTC) accounts for 10%–20% of all thyroid malignancies and is most likely to produce distant metastasis by hematogenous spread. The lung and bone (spine and pelvis) are the most common sites, while skull metastasis is rare and indicates advanced disease. Few cases have reported scalp swelling as the initial presentation, which warrants a quick imaging of the thyroid and biopsy of the lesion. We report a 56-year-old female with a 15-year history of neck swelling presenting with right head vertex swelling due to metastatic parietal involvement. Although fine-needle aspiration revealed a benign (Bethesda II) cytology, histopathology confirmed the widely invasive nature of the FTC, underscoring the significance of correlating radiological and clinical features when managing similar cases.