ANALYSIS OF CANCERS NOT DIAGNOSED AT STEREOTAXIC CORE BREAST BIOPSY

PURPOSE: To evaluate the mammographic and histopathologic features of carcinomas not diagnosed at stereotactic core biopsy. MATERIALS AND ME THODS: A retrospective review revealed 144 surgically confirmed carcin omas preoperatively sampled with stereotactic core biopsy. Diagnosis a t stereotactic core biopsy was carcinoma in 116 (81%) lesions, atypica l hyperplasia in 21 (15%), and benign findings discordant with those f rom mammography in seven (5%). Mammographic and histopathologic findin gs in the latter 28 cases were reviewed. RESULTS: Prompt repeat biopsy was recommended in all 28 casts. The frequency with which a cancer yi elded atypical hyperplasia at stereotactic core biopsy was higher for calcifications than masses (30% vs 5%, P < .0001), ductal carcinoma in situ (DCIS) than infiltrating carcinoma (33% vs 7%, P = .0002), and n oncomedo than comedo DCIS (60% vs 9%, P = .0008). No significant diffe rence was observed in the likelihood of benign core biopsy findings wi thout atypia in malignant calcifications versus masses (7% vs 3%, P = .43), DCIS versus infiltrating carcinoma (7% vs 4%, P = .43), or nonco medo versus comedo DCIS (0% vs 9%, P = .49). CONCLUSION: The likelihoo d of not diagnosing carcinoma was highest for calcifications and for n oncomedo DCIS. Discordance in mammographic and histopathologic finding s or the presence of atypical hyperplasia may enable the radiologist t o identify missed or underestimated carcinomas prospectively and avoid a delay in diagnosis.