Surgical biopsy is a method for diagnosing breast cancer. The aim of this study was to prospectively evaluate the relative accuracies of mammography (MMG) and ultrasound (US) in predicting residual disease following bioptic lumpectomy. Each prediction method was compared with the gold standard of surgical pathology. The results of MMG and US from 312 consecutive breast cancer patients diagnosed by surgical excision were analyzed. All the patients underwent re-excision mastectomy or lumpectomy and the imaging results were compared with the histopathological findings. The accuracy and sensitivity of each modality were investigated. A total of 312 patients with 312 primary breast cancers were investigated. Residual disease was identified in 118 patients. Of the 118 cases with residual disease, MMG and US were able to detect 77 (65.3%) and 32 (27.1%), respectively (chi-square P<0.001). MMG was also more sensitive compared with US in estimating residual ductal carcinoma in situ (DCIS) (94.2 vs. 33.3%, respectively; P<0.001). MMG was more accurate compared with US in detecting residual disease following bioptic lumpectomy and the diagnostic accuracy of MMG was associated with the presence of residual DCIS.
Keywords: breast cancer; lumpectomy; mammography; residual disease; ultrasound.