Abstract

A case of poorly differentiated "insular" carcinoma of the thyroid is presented and discussed with references to the literature. In fine needle aspiration cytology of our case, the aspirates were highly cellular with tumor cells appearing as dispersed isolated cells as well as in dense clusters and syncytial formations. Occasional microfollicles containing colloid were evident. Most of nuclei were fairly uniform with considerable variability and a few showed definite atypical features. Nuclear grooving was additional features. Necrotic debris was not seen. Our cytologic findings were correlated well with histology, confirming typical insular pattern of tumor cells with the presence of occasional pleomorphic cells and papillary carcinoma-like features. With much attention to cytological features of insular carcinoma, it would be possible to diagnose a preoperative suggestive diagnosis, even though not definitive.

• Keywords: Insular carcinoma;Thyroid;Fine needle aspiration cytology;