Stereotactic vacuum biopsy of calcifications with a handheld portable biopsy system: a validation study

Abstract

To prospectively evaluate a compact portable 10-gauge handheld battery-operated biopsy system for stereotactic biopsy of microcalcifications. The ethics committee of the hospital approved this prospective multicentric study, and informed consent was obtained. Biopsy under stereotactic guidance was performed in 215 patients for 219 lesions consisting of microcalcifications without mass. The feasibility and the tolerance of the procedure were evaluated. The mean weight of the specimen was calculated. In patients with surgical diagnoses, the underestimation rate in biopsy diagnoses of atypical ductal hyperplasia and ductal carcinoma in situ were evaluated. The sampled specimens were separated according to the presence of calcifications on magnified specimen radiographs and to the probe the rotation number in order to evaluate the contribution of each rotation and the contribution of the specimen with and without calcifications on the radiographs. The macrobiopsy was feasible in 98.5% of the patients and was well tolerated in 82% of patients. It identified 4.6% invasive carcinomas, 18.5% ductal carcinomas in situ, 14.8% atypical ductal hyperplasias, 22.2% benign proliferative mastopathies and 39.8% benign non-proliferative mastopathies. The underestimation rate was 26.6% when an atypical ductal hyperplasia was diagnosed at biopsy, and 7.7% when a ductal carcinoma in situ was diagnosed. In the 77 patients with surgical correlation, the accurate diagnosis was obtained in specimens sampled during the first, second, and third in 69%, 9%, and 4% of the biopsies, respectively, and the analysis of specimens without microcalcification had an added value in 8% of patients. The compact portable battery-operated biopsy system can be used successfully for stereotactic biopsy of microcalcifications and constitutes a valid alternative to current systems.