[Predictive factors for malignancy in breast microcalcifications without associated lesions]

Screening mammography allows the early detection and treatment of nonpalpable carcinomas. Microcalcifications are highly important for the detection of many of these malignancies but are also present in benign breast disease. In the present study we analyzed the radiologic and clinical factors associated with malignancy.

We retrospectively reviewed 133 patients who underwent open biopsy after a mammographic finding of microcalcifications without an associated lesion. Clinical and radiologic characteristics were correlated with histologic findings.

A total of 28.6% of the lesions analyzed were malignant. Of these, 65.8% were ductal carcinoma in situ. Among invasive carcinomas, 23.1% presented lymph node metastasis. No clinical criterion was significant for malignancy. On univariate analysis six radiologic criteria were significant: morphologic type (Le Gal's classification), irregularity of size, irregularity of density, number of microcalcifications per cluster, diameter of the lesion, and the presence of more than one cluster. On multivariate analysis the factors with independent predictive value were: irregularity of density, > or = 10 microcalcifications per cluster, the presence of more than one cluster, and diameter of the cluster > or = 10 mm.

Although none of the clinical factors analyzed was predictive for malignancy, the radiological characteristics of microcalcifications were determining factors in the indication for biopsy.