Indicators of multifocality in papillary thyroid carcinoma concurrent with Hashimoto's thyroiditis.

Currently, no definitive diagnostic tool is available to distinguish unifocal and multifocal papillary thyroid carcinoma (PTC). This study aims to identify potential diagnostic markers of multifocal PTC. In 471 Hashimoto's thyroiditis (HT) patients, the significant difference was revealed in anti-thyroid peroxidase antibody (TPOAb) concentration, the cytokeratin-19 (CK-19) expression, the occurrence of the B-Raf proto-oncogene serine/threonine kinase (BRAF) mutations and the rearrangement in transformation (RET)/PTC.