DISEASE CHARACTERISTICS: Mammogram highly suspicious for ductal carcinoma in situ or early invasive carcinoma Branching or linear microcalcifications clustered or distributed segmentally in the breast without an associated palpable or mammographic mass Palpable thickening or nipple discharge allowed At least 5 mm area of calcification or contain enough calcium for core biopsies Small palpable carcinoma (T1 or T2) with no palpable axillary lymph nodes (N0) No definitive local therapy Atypical hyperplasia (ductal or lobular) and/or carcinoma on initial diagnostic biopsy Hormone receptor status: Not specified