Thyroid nodules with indeterminate cytopathology: a constant challenge in everyday practice. The effectiveness of clinical decisions using diagnostic tools available in Poland

A crucial issue in the management of thyroid nodules is to estimate, as accurately as possible, the malignancy risk in thyroid lesions. The key tool for risk stratification is fine needle aspiration biopsy. Unfortunately, approximately 20 % of biopsy results are indeterminate. The malignancy risk assigned to these categories does not allow unequivocal further management. We aimed to assess the malignancy risk in indeterminate thyroid nodules in the Polish population, and to analyze the effectiveness of clinical decisions after an indeterminate cytological diagnosis in Polish clinical practice. The retrospective analysis included 222 indeterminate thyroid nodules in 222 patients. The ultrasound features were assessed from scans preceding a thyroid biopsy. Cytology results were classified according to the Bethesda system. The nature of the thyroid nodule was determined on the basis of a histopathological analysis or follow up. The analyzed cohort included 82 lesions in Bethesda category III, 75 in Bethesda category IV and 65 in Bethesda category V. The malignancy risk, estimated on the basis of histological verification and surveillance was 6.7% for Bethesda III, 11.3% for Bethesda IV and 70.3%for Bethesda V category. An ultrasound pattern was not effective enough for refining the malignancy risk after obtaining an indeterminate cytopathology result. In the case of surgery, postoperative hypoparathyroidism was significantly more frequent following more extensive surgical procedures. Majority of Polish patients with thyroid nodules assigned to cytological categories Bethesda III and IV is overtreated using diagnostic tools currently available in Poland.