ACTA ENDOCRINOLOGICA (BUC)

Purpose. To investigate the association between papillary thyroid cancer (PTC) and Hashimoto’s thyroiditis (HT). Design. This study is a retrospective study that conducted during 7 consecutive years with a median 119.5 months follow-up. Subjects and Method. Patients who underwent thyroidectomy in Dokuz Eylül University Hospital during 7 consecutive years were included. Patients’ demographics, biochemical, radiological, and pathological results were retrospectively assessed. Results. Four hundred sixty nine patients were evaluated. Among 469 patients who underwent thyroidectomy, 132 (28.1%) were malignant, while 182 patients were diagnosed with HT (38.8%). PTC was ranked first at 92.4% (n: 122). The prevalence of HT was 54.9% in patients with PTC and 33.1% in patients without PTC diagnosis (p<0.001). Younger age and the presence of HT were independently associated with PTC. The presence of HT was associated with increased risk of development of PTC (OR: 2.2, %95 CI: 1.4-3.5, p<0.001) but not with TNM stage or recurrence. Lymph node metastasis at presentation was the strongest predictor of recurrence (OR: 13.9, CI: 3.5-54.6, p<0.001) Conclusions. HT was an independent risk factor for development of PTC. According to our findings, HT patients (particularly with nodular HT) should be observed carefully and thyroid fine needle aspiration biopsy (TFNAB) should be encouraged if necessary.