Retrospective multivariate analysis of radio-pathological correlations of nonpalpable breast lesions. Experience of the Hospital Saint-Louis

PURPOSE: Several studies have demonstrated that systematic breast cancer screening increases overall survival. We report our experience regarding diagnosis of breast lesions detected using mammography. METHODS: Case reports of patients operated on in either 1992 or 1993 were retrospectively reviewed. A multivariate analysis of the clinico-pathological correlation was performed. RESULTS: Four hundred fifty seven patients representing on total 544 procedures, were included in the study. Mean age was 50.5 years (range 19-80 years). Most of the patients had no previous history of mammary lesion. Mammography was performed with prophylactic intent in more than 60% of the cases. Four hundred twelve (75.7%) benign lesions were diagnosed. Main lesions were: adenofibroma (15.7%), fibrocystic mastopathy (66.3%), adenosis (26.2%), ductal hyperplasia (23.9%), lobular hyperplasia (10.7%), and combined ductal and lobular hyperplasia (8.5%). Hyperplasia accompanied by cytonuclear atypia was observed in 49 (11%) cases. One hundred thirty two (24.3%) malignant lesions were reported, including 69 (52.3%) invasive carcinomas and 63 (47.7%) in situ carcinomas. Only nine axillary lymph node dissections were positive and 75 minimal breast cancers were diagnosed. The multivariate analysis showed that only radiological signs are a risk factor for cancer. The relative risk for cancer when focus of irregular and vermicular microcalcifications are diagnosed is 4.2 (2.0-8.5). It is 5.6 (2.5-12.5) in case of spiculated opacity. CONCLUSION: Exeresis following radiological prophylactic screening allows diagnosis of high-risk benign lesions and low-stage breast cancer. Radiological parameters are the most powerful predictive factors for malignancy.