Aggressive histopathological variants of papillary thyroid carcinoma, diagnostic challenge, and clinical significance—A case series

Papillary thyroid carcinoma is the most common form of thyroid cancer and is usually associated with a good outcome. However, there are some aggressive variants wherein the prognosis may not be as good as for a conventional papillary thyroid carcinoma. Three cases of aggressive variants of papillary thyroid carcinoma are reported in the present series, namely, tall cell, hobnail, and columnar cell variants. This series is being reported to highlight the characteristic histopathological features which help in diagnosing these variants, especially diagnostic challenge in recognizing columnar cell variant due to lack of the classical nuclear features of papillary thyroid carcinoma in this variant. This case series also highlights the clinical importance of recognizing these variants because, according to American Thyroid Association, these variants come under intermediate risk with a poor clinical outcome, requiring aggressive management with neck dissection, radioiodine ablation, and closer disease surveillance.