Intraepithelial neutrophils in thyroid fine-needle aspiration: A portent of aggressive thyroid cancer?

Abstract

We report three patients with papillary thyroid carcinoma in whom fine-needle aspiration (FNA) showed neutrophils within tumor cells. All three patients presented with large neck masses; at excision, two proved to be tall cell variants of papillary cancer. Nodal metastasis, extrathyroidal extension, and vascular invasion were found in both cases. One patient has experienced recurrent disease; the other has an increasing thyroglobulin titer but no clinically appreciable recurrence. The third patient refused further therapy, but brain metastases were noted clinically; this patient died of disease. In each case, FNA showed tumor clusters with characteristic nuclear features, papillary groups, and psammoma bodies. Neutrophils were present in the cytoplasm of tumor cells in the absence of necrosis. Immunostaining for proliferating cell nuclear antigen (PCNA), MIB-1 (Ki-67), and p53 tumor suppressor gene product was markedly positive. lntraepithelial neutrophils have not been previously reported in differentiated thyroid tumors. We postulate that these neoplasms produce specific leukocyte-attracting cytokines analogous to those produced by anaplastic and poorly differentiated thyroid carcinomas. We believe the finding of intraepithelial leukocytes in the absence of necrosis in thyroid FNA specimens represents a characteristic of clinically aggressive differentiated papillary neoplasms; in our small series, each represented a tall cell variant of papillary carcinoma.

Potential involvement of neutrophils in human thyroid cancer

“…PMNs infiltrate different types of human tumors [ 23 ]. With the exception of some case reports [ 54 ], to our knowledge, there is no information concerning the presence and significance of tumor-infiltrating PMNs in human TC. Therefore, we assessed the occurrence of CD66b + PMNs by immunohistochemistry in tumorous thyroid tissue samples.…”

An Increased Neutrophil-to-Lymphocyte Ratio Predicts Incomplete Response to Therapy in Differentiated Thyroid Cancer

“…Contrary to anaplastic thyroid cancer, intratumoral neutrophil infiltration is rarely seen in the absence of necrosis. Nonetheless, neutrophil infiltration in differentiated thyroid cancer, when present, may portend an aggressive phenotype 21.…”