THYROID ANTIBODIES IN ASSOCIATION WITH THYROID MALIGNANCY .1. SIMULTANEOUS OCCURRENCE OF THYROIDITIS AND THYROID MALIGNANCY

Occurrence of thyroid antibodies and thyroiditis in association with thyroid malignancy, suspected malignancy or other thyroid diseases was studied in 177 patients. Retrospective clinical analysis revealed that 137 patients had thyroid carcinoma (108 papillary carcinomas, 10 occult papillary carcinomas. 14 follicular carcinomas, and 5 other carcinomas) and 40 had other thyroid diseases. Thyroid microsomal (AMC) and thyroglobulin antibodies (ATG) were measured by the particle agglutination method. Clinically significant thyroid antibody titers and histological or clinical features of thyroiditis were seen in nine patients with thyroid carcinoma, being equally prevalent in follicular and papillary carcinomas. Taking into account the prevalence of positive AMC antibodies and thyroid carcinoma in Finland, the highest predicted prevalence of simultaneously occurring thyroid carcinoma and thyroiditis in the under 40 age group should be 0.002% and in the over 40 age group 0.006%. In the present material the observed occurrences in corresponding age groups were unexpectedly high (4.7% and 5.2%). The results may partly be due to patient selection, but they also suggest that there might be a link between thyroiditis and thyroid carcinoma.