Modified core wash cytology (CWC), an asset in the diagnostic work-up of breast lesions

Aim: A quick and reliable preliminary diagnosis is essential in the management of a same-day breast clinic. In a preclinical study we developed an alternative method of core wash cytology (CWC). This study is an evaluation of this new CWC method introduced into the clinical setting. Methods: From April 2008 to April 2009, biopsies were taken from lesions in the breast. CWC was obtained from core needle biopsy (CNB) with a modified technique and classified into the categories: malignant, suspicious for malignancy, atypical, benign and inadequate. CWC and CNB diagnoses were correlated with the histopathology of subsequently obtained resection specimens. The sensitivity and specificity were calculated. Results: CWC was obtained from 226 breast lesions. In 167 of these cases subsequent resection of the lesion was performed revealing 149 carcinomas and 18 benign lesions. Of the 149 malignant cases, 136 were considered as either malignant or suspicious for malignancy by CWC, 7 as atypical, 4 as benign and 2 as inadequate. None of the 18 benign lesions were classified as suspicious or malignant on CWC. Eight out of 149 resected carcinomas were not recognized as malignant by histological analysis of the CNB, while 7 of these cases the CWC was considered malignant. The sensitivity and specificity were 97% and 100%, respectively. Conclusions: In the vast majority of patients the modified CWC technique can provide a quick and reliable diagnosis of malignant breast lesions. Furthermore, combining CWC with CNB histology can improve adequate, preoperative recognition of the malignant character of breast lesions.