A man in his 60s presented with neck swelling. On physical examination a diffusely hardened thyroid gland and multiple neck lymphadenopathies were found. Contrast-enhanced chest and neck computed tomographic (CT) imaging revealed multiple cervical lymph nodes and diffuse thyroid heterogeneity with a low-density nodule in the right lobe. No thoracic lesions were observed. Rigid laryngoscopy, thorough head and neck examination, as well as whole-body positron emission tomographic imaging excluded tumors from the upper aerodigestive tract or distant metastasis. A fine-needle aspiration cytologic specimen of the cervical lymph node revealed necrosis and atypical squamous cells. Total thyroidectomy combined with bilateral neck lymph node dissection was performed. The surgical specimen revealed an ill-defined, nonencapsulated tumor (52 × 32 × 25 mm) involving the whole thyroid gland (Figure, A). Histopathologic findings showed a neoplastic cell proliferation, forming sheets, nests, and compact masses that invaded the stromal thyroid tissue. The tumor cells revealed scant eosinophilic cytoplasm with individual keratinization. Periodic acid–Schiff (PAS) and Alcian blue stains were negative for mucin deposits. The surrounding stroma showed squamous metaplasia and lymphocytic infiltration exhibiting large follicles with prominent germinal centers (Figure, B). Extrathyroid infiltration, comedo necrosis, and extensive lymphovascular invasion were observed. There were no histologic findings suggestive of preexisting papillary, medullary, or anaplastic or undifferentiated carcinoma. The immunohistochemical profile of the tumor cells revealed strong positivity for p63 (Figure, C) and CK5/6, 34betaE12, CK (AE1/AE3), and CK19 antibodies. Results for PAX-8 were moderately positive (Figure, D). Results for CD5, calcitonin, thyroglobulin, TTF-1, CD56, and CEA antibodies were all negative. Regional metastases were detected in 58 of 67 lymph nodes examined on the right side and 43 of 67 on the left side.
Machado I, Arana E, Vendrell J. A Diffusely Hardened Thyroid Gland and Multiple Neck Lymphadenopathies. JAMA Otolaryngol Head Neck Surg. 2015;141(2):181-182. doi:10.1001/jamaoto.2014.3171