Mammographic findings in pseudoxanthoma elasticum

There have been isolated case reports of arterial and skin calcification in mammograms of patients with pseudoxanthoma elasticum (PXE), and unpublished anecdotes of many women with PXE undergoing breast biopsy for evaluation of microcalcifications.

Our aim was to systematically evaluate mammography and breast pathology in PXE.

The mammograms of 51 women with confirmed PXE were compared with those of a control sample of 109 women without PXE, noting each of the following characteristics on each mammogram: breast density, skin thickening, skin microcalcifications, vascular calcification, breast microcalcifications and macrocalcifications, and masses. The characteristics of the 2 samples were compared using the 2-tailed t test with a pooled estimate of variance. The indications for mammography and data for each of the mammographic findings were analyzed using the chi(2) test. Available breast biopsy material was reviewed.

The PXE and control groups were similar in age and indications for mammography. There was a statistically significant increase in skin thickening, vascular calcification, and breast microcalcifications in the PXE group (P <.001 each). Breast density, masses, macrocalcifications, and skin calcification did not differ statistically in the 2 groups, but no control patient had axillary calcification, or both vascular calcification and microcalcifications (P <.001). Nearly 1 in 7 of the patients with PXE demonstrated at least 3 of the following: microcalcifications, skin calcifications, vascular calcification, and skin thickening; whereas none of the control group did. Histopathologic findings of breast tissue showed calcification of dermal elastic fibers, subcutaneous arteries, and elastic fibers of the deep fascia and interlobular septae of the fat adjacent to breast parenchyma.

Breast microcalcification and arterial calcification are not rare in the normal population and are not of diagnostic value. The presence of both of these findings, especially with skin thickening or axillary skin calcification, should suggest a diagnosis of PXE. The majority of breast calcifications in PXE are benign.