Evaluation of cytopathological findings in thyroid nodules with macrocalcification: macrocalcification is not innocent as it seems.

OBJECTIVE: Microcalcification is strongly correlated with papillary thyroid cancer. It is not clear whether macrocalcification is associated with malignancy. In this study, we aimed to assess the result of fine needle aspiration biopsies (FNAB) of thyroid nodules with macrocalcifications.

SUBJECTS AND METHODS: We retrospectively evaluated 269 patients (907 nodules). Macrocalcifications were classified as eggshell and parenchymal macrocalcification. FNAB results were divided into four groups: benign, malignant, suspicious for malignancy, and non-diagnostic.

RESULTS: There were 79.9% female and 20.1% male and mean age was 56.9 years. Macrocalcification was detected in 46.3% nodules and 53.7% nodules had no macrocalcification. Parenchymal and eggshell macrocalcification were observed in 40.5% and 5.8% nodules, respectively. Cytologically, malignant and suspicious for malignancy rates were higher in nodules with macrocalcification compared to nodules without macrocalcification (p = 0.004 and p = 0.003, respectively). Benign and non-diagnostic cytology results were similar in two groups (p > 0.05). Nodules with eggshell calcification had higher rate of suspicious for malignancy and nodules with parenchymal macrocalcification had higher rates of malignant and suspicious for malignancy compared to those without macrocalcification (p = 0.01, p = 0.003 and p = 0.007, respectively).

CONCLUSIONS: Our findings suggest that macrocalcifications are not always benign and are not associated with increased nondiagnostic FNAB results. Macrocalcification, particularly the parenchymal type should be taken into consideration.