IntroductionEvaluation for the spread of breast cancer with microcalcifications is challenging, because the microcalcifications sometimes spread beyond the lesions detectable by ultrasonography (US). An original method for preoperative mapping was performed for such lesions, using US in combination with mammography (MG) (US + MG mapping) before breast-conserving surgery (BCS). Materials and MethodsA total of 885 consecutive patients underwent BCS for primary breast cancer. Of the 885 patients, 154 (17.4%) with ductal carcinoma in situ or invasive carcinoma having microcalcifications underwent US + MG mapping preoperatively. Five patients who received neoadjuvant chemotherapy and 17 patients who were lost to follow-up were excluded. Accordingly, 133 lesions in 132 patients were retrospectively evaluated. The associations among this method, surgical margin (positive, close, or negative), pathologic characteristics, the area of the lesion within the specimen, and local recurrence rate during 5 years of follow-up were analyzed. ResultsThe median age and follow-up duration were 51.3 years (range, 28-80 years) and 71.4 months (range, 60-79 months), respectively. The surgical margin was negative in 96 lesions (72.2%), close in 27 lesions (20.3%), and positive in 10 lesions (7.5%). Local recurrence was noted in 1 patient (0.8%). There was no significant association between surgical margin status and the presence of invasive carcinoma. Larger lesion area was significantly associated with positive or close margin (P = .027). ConclusionUS + MG mapping is useful and results in a high complete-resection rate and an extremely low 5-year local recurrence rate.