Rapid on-site cytologic examination of 1500 breast lesions using the modified Shorr’s stain

Abstract

Rapid on-site evaluation (ROSE) cytology enables sample quality assessment in the procedure room and facilitates the process of examination. While its use for mammary lesions in one-stop breast clinics has been reported, its usefulness as a cytologic diagnostic tool has not been fully explored. A total of 1500 examinations of core-needle biopsy imprint/fine-needle aspiration cytology were performed for outpatients with breast lesions. The slides were immediately processed with modified Shorr's stain, which can be completed within a few minutes yet produces specimens of similar staining quality as the Papanicolaou (Pap) stain. The adequacy of sampling was evaluated on site, and a cytologic diagnosis was also made. ROSE cytologic findings were classified into five grades: class 1, inadequate; class 2, benign; class 3, indeterminate; class 4, suspicious for malignancy; class 5, malignant. If enough epithelial cells could not be obtained despite repeated examinations, the sample was scored as ineligible. These scores were utilized for patient management. Final cytologic diagnoses were made with conventional Pap stains. Reproducibility of scores between both staining methods was excellent (weighted κ statistic=0.985). When compared class by class, concordance of cytologic diagnoses was particularly high in class 2 and 5 Shorr scores, in which the agreement with Pap diagnoses was 92.8 and 93.6%, respectively. Our modified Shorr's staining protocol was useful to reduce the time for the diagnosis and treatment planning of breast lesions suspected of being breast cancer. It is beneficial for both the patients and clinicians.