Thyroid Nodules in a Veterans Affairs Population

Abstract

Objective: 1) Determine if follicular thyroid lesions in a Veteran Affairs (VA) population are at increased risk of harboring malignancy compared to the general population. 2) Analyze imaging modalities leading to diagnosis. Method: Retrospective analysis of 107 patients undergoing partial or total thyroidectomy from 2005 to 2010 at a single Veteran Affairs hospital. Outcome measures included age, sex, method of nodule detection, fine needle aspiration (FNA) cytopathology, final histopathology, associated 2deoxy-2[18F]fluoro-D-glucose positron emission tomography (FDG-PET) uptake, and incidence of cancer compared with previously published data. Results: Age range was 27 to 84 years (mean, 60 years). Fine needle aspiration (FNA) cytopathology results were benign in 31% (n = 33), follicular lesion in 41% (n = 46); suspicious for malignancy or malignant in 11.2% (n = 12). The overall malignancy rate was 36.4% (n = 39). Of the indeterminant FNA lesions, 41% (n = 19) had malignancy confirmed histopathologically. This is higher compared to recently published rates of malignancy in follicular lesions (15%-30%). In 9 of the 10 patients who underwent 2deoxy-2[18F]fluoro-D-glucose positron emission tomography (FDG-PET), focal thyroid uptake was identified and was significantly ( P < .01) associated with malignancy. This percentage is also much higher prevalence than the approximately 33% reported. Conclusion: Follicular thyroid nodules of undetermined significance on FNA may harbor malignancy more frequently in the VA population compared to the general population. Focal FDG-PET uptake is significantly associated with malignancy.