Mammographic features of local recurrence after conservative surgery and radiation therapy: Comparison with that of the primary tumor

Purpose: To compare the mammographic features of recurrent breast cancer with those of the primary tumor and to determine whether certain mammographic features are associated with a higher risk of local recurrence after breast-conserving therapy. Material and Methods: A retrospective review of mammograms of 421 patients who were treated with conservative surgery and radiotherapy revealed 41 recurrent tumors. Mammographic findings, location, and histopathologic characteristics were retrospectively compared between primary and recurrent tumors. Results: Recurrent tumors were similar in mammographic appearance to primary tumors in 27 (66%) cases. Of 27 primary tumors that occurred as masses without calcifications, 19 (70%) recurred as a mass, and of the six isolated calcifications, five (83%) recurred with calcifications. Ten (53%) of the 19 recurrent masses and five (100%) of the five recurrent calcifications had morphologic features that were similar to those of the primary tumor. Ninety-two percent (11/12) of the recurrences containing microcalcifications ( isolated or associated with a mass) had microcalcifications in their primary tumor. Of 27 masses that recurred, the morphology of the primary tumor was obscured in 13 (48%), ill defined in 10 (37%), and spiculated in four (15%) of the masses. Seventy-six percent (31/41) of recurrences were within the lumpectomy quadrant. In 25 (61%) cases, the histologic findings from the primary tumor and the recurrence were identical. Conclusion: The majority of recurrent tumors appear to be mammographically similar to primary tumors. Therefore, it is important to review preoperative mammograms during follow-up of these patients. Although the study population is small, it was noted that mass with spiculated contour is associated with a lower risk for local recurrence.