Predicting local recurrence by correlating pre-operative mammographic findings with pathological risk factors in patients with breast cancer.

The pre-operative mammograms for 231 patients undergoing conservation surgery for breast cancer between March 1988 and September 1992 were analysed for features that may predict the presence of pathological risk factors of local recurrence (residual microscopic disease, extensive intraduct carcinoma (EIC) and lymphatic/vascular invasion). Residual microscopic disease was detected in 40% of patients and was associated with a DY mammographic pattern (p = 0.03), casting calcification (p = 0.0002) and absence of mammographic nidus (p = 0.0006). Residual microscopic disease was found in 75-88.9% of patients when two of these preoperative mammographic features were present in combination. The mean lumpectomy diameter was significantly smaller for patients with DY compared to N1 mammographic pattern on Wolfe grade (p = 0.039). Both residual disease and Wolfe grade were related to age (p = 0.0032 and p < 0.0001). EIC was found in 22% of patients and was associated with casting (p < 0.0001) and non-casting (p = 0.04) calcification, absence of mammographic nidus (p < 0.0001) and stellate mammographic nidus (p = 0.02). No significant association was found between mammographic features and lymphatic/vascular invasion. Pre-operative mammographic features can predict patients likely to have residual microscopic disease or EIC following conservation surgery for breast cancer. These patients should be selected for wider primary excision.