Coexistent disease as a complicating factor in the fine needle aspiration diagnosis of papillary carcinoma of the thyroid.

The occasional coexistence of papillary carcinoma of the thyroid with nodular goiter or hyperparathyroidism may in some cases result in a significant discrepancy between the clinical impression and the fine needle aspiration (FNA) biopsy diagnosis, leading to the suspicion that a false-positive FNA diagnosis was obtained. Two such cases are presented in which consultation between the cytopathologist and the surgeon was helpful in achieving a correct diagnosis and ensuring proper therapy. Awareness of these variations in the clinical presentation of papillary carcinoma of the thyroid will aid the cytopathologist in the resolution of such apparent discrepancies.