Utilization of core wash material in the diagnosis of breast lesions by stereotactic needle biopsy.

Abstract

Several reports have compared the results of fine-needle aspiration and stereotactic core needle biopsy in nonpalpable breast lesions. In this study the authors describe a simple method to retrieve cytologic material from a core breast biopsy sample that provides the diagnosis within 1 hour of the procedure. Two hundred and eleven nonpalpable breast lesions were biopsied. Each core needle biopsy sample was placed in a mesh bag, and the bag and needle notch were washed in Cytolyt solution to obtain a monolayer using a commercial ThinPrep processor. The cytologic diagnoses were divided into four categories: benign, suspicious, malignant, and unsatisfactory, which then were compared with core needle biopsy results. Cytology reports of 211 lesions were as follows: 169 lesions (80%) were benign, 16 lesions (7.6%) were suspicious, 11 lesions (5.2%) were malignant, and 15 lesions (7.1%) were unsatisfactory. Core needle biopsy showed 165 of 169 samples (98%) to be benign and 4 to be malignant. Of the 16 suspicious smears, 10 were invasive carcinoma, 2 were in situ lesions, 3 were hyperplasias, and 1 was fibrosis. Of the 11 malignant smears, 10 were confirmed on core needle biopsy and 1 was read as atypia on the first core needle biopsy sample and malignant on a second, separate, follow-up core needle biopsy. Of the 15 unsatisfactory samples, 14 were found to be benign and 1 was found to be malignant on a separate, follow-up core needle biopsy. The core wash technique was 85% sensitive and 98% specific for malignancy. Only 7% of specimens were insufficient for diagnosis, and 93% of these were proven to be benign. This technique is useful for immediate (within 1 hour) diagnosis of breast lesions, alleviating patient anxiety and supplementing the diagnostic yield of the core biopsy.