Underestimation of breast cancer with II-gauge vacuum suction biopsy

OBJECTIVE. The purpose of this study was to determine the mammographic and histologic features of cancerous lesions underestimated using 11-gauge vacu um suction biopsy. MATERIALS AND METHODS. Retrospective review of 11-gauge vacuum suction biop sy was performed to identify lesions diagnosed as atypical ductal hyperplas ia or carcinoma. The histology of the core and surgical specimens was compa red. Of 158 cases of cancer, underestimation occurred in 15 (9.5%). The mam mographic and histologic features were assessed. RESULTS, Of 15 underestimated cases, six were atypical ductal hyperplasia t hat proved to be cancer (5 duct al carcinoma in situ and 1 invasive) and ni ne were ductal carcinoma in situ that proved to have invasion. The underest imation rate for calcifications was 16.3% (14/86) and for masses was 1.6% ( 1/64) (p = 0.007). Most (5/6) underestimated atypical ductal hy perplasia c ases were reported as "markedly atypical:" and four of nine underestimated ductal carcinoma in situ cases were reported as "possible invasion." No sig nificant difference was seen in the number of core specimens obtained or th e sizes of the lesions for underestimated cases versus accurately diagnosed cases. The percentage of calcifications retrieved was significantly differ ent (p = 0.017). No underestimations were found among cases in which the en tire mammographic lesion was removed at vacuum suction biopsy. CONCLUSION. The cancer underestimation rate with vacuum suction biopsy was 9.5%, The underestimation rate for calcifications (16.3%) was significantly higher than that for masses (1.6%) (p = 0.007), The percentage of the lesi on removed was an important factor in reducing underestimation, as reflecte d by the percentage of calcifications retrieved and the instances of comple te resolution of the lesion seen on mammography.