Do Intranodular Macrocalcifications Really Play an Important Role in Sonographic Prediction of Malignancy?

• The authors have no financial conflicts of interest. which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. issue of YMJ, is a well-written paper and we want to acknowledge Park, et al. 1 for their comprehensive article on malignant thyroid nodules with macrocalcification as it provides important informations with which to potentially diagnose malignant thyroid nodules. Nevertheless, we would like to discuss a few points of emphasis on the general profile of thyroid nodules and their calcifications, especially the description and analysis of macrocalcification and rims of soft tissue around calcified zones. In this paper, the authors reported that echogenic foci of calcification larger than 1 mm at the longest diameter were considered as representative of macrocalcifica-tions, that bright echoes of less than 1 mm with or without acoustic shadowing were accepted as microcalcification and that combination of micro-macrocalcifica-tions in a nodule was classified as a nodule with microcalcification and excluded from the study. However, we believe that, utilizing a thin slight borderzone with a threshold size of 1 mm to distinguish between micro and macrocalcifications can create serious bias in the statistical analysis and would definitely affect the results of the research, especially the sensitivity and positive predictive values (PPV) for sonography in differentiating between malignant and benign nodules, according to intranodular calcification size. In previous reports, generally, 2 mm was considered as the cutoff value between micro and macrocalcifications, in which bright and granular calcifications ≤2 mm in diameter, with or without acoustic shadows, were considered to be mi-crocalcifications; meanwhile calcifications with a maximum diameter >2 mm, including lumpy, irregular, peripheral, eggshell and coarse calcifications, were defined as macrocalcifications. As no data on the size, nature, and number of nodules and macrocalcification patterns were given, we have serious suspicions about the accuracy of the results of this original research. We believe that the authors took the threshold value of 1 mm for distinguishing benign and malignant nodules in order to perform a diagnostic fine-needle aspiration biopsy (FNAB) and to avoid having inadequate sampling of FNAB-cytology due to larger calcifica-tions; the authors reported a high rate of unsuccessful biopsy sampling in nodules with macrocalcification (21%). Such non-diagnostic cytology would also limit the efficacy of sonography in predicting the malignant nature of such nodules. Like the calcification widths, existence of a 1 mm or larger soft tissue rim cir-cumscribing macrocalcification …