Warthin-like papillary carcinoma of the thyroid: a case series and review of the literature.

Warthin-like tumor of the thyroid is a recently described rare variant of thyroid papillary carcinoma. The distinguishing histological feature of this variant is papillary foldings lined by oncocytic neoplastic cells with clear nuclei and nuclear pseudoinclusions, accompanied by prominent lymphocytic infiltrate in the papillary stalks. Its prognosis has been reported to be almost similar to conventional papillary carcinoma. In this case series, we report four cases with Warthin-like papillary carcinoma of the thyroid, diagnosed at Dokuz Eylul University Faculty of Medicine Department of Pathology in 2008 and 2009. Three patients were female. The mean patient age was 39 years (range, 20-56) and the mean tumor size was 1.7 cm (range, 0.9-2.0 cm). All of the cases had lymphocytic thyroiditis in the background. None of the tumors showed lymphovascular invasion. The patients are free of any recurrence and/or distant metastasis with a mean follow-up of 25 months. This rare variant of thyroid papillary carcinoma with distinct histopathological features should be indicated in pathology reports. Further studies and long-term follow-up of patients are needed to highlight the biological behavior of this variant.