Mammographic pattern of microcalcifications in the preoperative diagnosis of comedo ductal carcinoma in situ: histopathologic correlation

Objective: The comedo subtype of ductal carcinoma in situ (DCIS) is more ag gressive than noncomedo DCIS. Differentiating noncomedo DCIS from the more aggressive comedo subtypes on mammography would allow the surgeon to excise comedo DCIS with a wider margin. The mammographic features of microcalcifi cations associated with nonpalpable comedo DCIS, noncomedo DCIS and benign disease were compared to determine the usefulness of this finding in diagno sis of comedo DCIS. Methods: The authors retrospectively and blindly review ed the mammograms of 91 consecutive patients in whom DCIS was diagnosed by needle localization and surgical excision. An equal number of cases of beni gn microcalcifications were also reviewed. Microcalcifications were evaluat ed with respect to pattern, density, configuration and size. These results were correlated with the pathologic findings. Results: All 16 cases (100%) of linear branching calcifications and 34 (80%) of the 43 cases of linear c alcifications were associated with comedo DCIS (p < 0.001). The number of c alcifications, the density and the size of clustering were not diagnostic o f comedo DCIS. Granular calcifications occurred in noncomedo DCIS and in be nign disease associated with noncalcifying DCIS. Conclusion: Comedo DCIS is suggested by the presence of linear and linear branching microcalcificatio ns on mammography.