Excessive survivin expression in thyroid lymphomas.

Thyroid lymphoma occurs most commonly in the thyroid glands with a background of Hashimoto's thyroiditis. Therefore, it is occasionally difficult to distinguish lymphoma from Hashimoto's thyroiditis because of some cellular and histologic similarities. We have examined whether survivin or human telomerase reverse transcriptase (hTERT) expression can differentiate between the 2 disorders. Surgically removed tissue samples from 6 patients with thyroid lymphoma and 6 patients with Hashimoto's thyroiditis were analyzed for mRNA levels of survivin and hTERT by real-time quantitative reverse-transcription polymerase chain reaction. Expression of survivin protein was examined by immunohistochemical stain using a polyclonal antibody. Survivin mRNA levels were greater in thyroid lymphoma than in Hashimoto's thyroiditis: 49.1 +/-36.4 versus 6.6 +/-2.7 pg/ng rRNA (mean +/- SD) (P <0.005). Immunohistochemical stain confirmed an abundance of survivin protein in lymphoid cells of thyroid lymphoma. The amount of hTERT mRNA did not differ in the 2 disorders. Our study shows that measuring survivin mRNA levels or immunohistochemistry of the protein expression can be useful to aid the diagnosis of thyroid lymphoma when histologic diagnosis is difficult. Copyright 2002, Elsevier Science (USA). All rights reserved.