Finding the Missing Calcifications: How Deep to Cut?

Abstract

Abstract Introduction/Objective Mammographic documentation of microcalcifications requires biopsy of the microcalcifications with histologic study to demonstrate that the area of mammographic interest is examined histologically to exclude carcinoma. Initial levels may not demonstrate these microcalcifications requiring study of additional levels. Little data exists as to how deeply levels should be cut to document microcalcifications. Methods/Case Report A search of pathology records at the University of Missouri between January 1, 2022 and March 30, 2023 for reports containing the term “microcalcifications” in the clinical history or specimen designation was performed. For each identified case, all slides of blocks designated by the radiologist as containing microcalcifications were pulled for review. Our protocol was to cut initially two levels separated by 50 microns. If no microcalcifications were detected an additional 10 levels each separated by 100 microns were examined. The level at which microcalcifications were first detected was recorded. Results (if a Case Study enter NA) The search revealed four-hundred and thirty-one specimens meeting study criteria. Four-hundred and fifteen of these samples contained microcalcifications on histologic examination. Probability of finding microcalcifications in the initial level was 0.629 and 0.935 in the first six levels. The incremental cost per calcification was 1.5 for the first level and 66.7 for the sixth level. The relative cost per calcification in level 6 was 44.5. Levels beyond level 6 rarely disclose microcalcifications. Conclusion 94% of microcalcifications documented by imaging were detected histologically in the first six levels using our protocol. The six-level protocol appears optimal for detection of microcalcifications. This study has significant implications for other specimen types. When a strong suspicion for a pathologic lesion is present on imaging but histologic sampling reveals no lesion, four further levels cut at 100 microns should be obtained.