Use of imprint cytology for assessment of surgical margins in lumpectomy specimens of breast cancer patients

Abstract

In the past several years, breast-conservation therapy has provided an alternative to mastectomy. In order to reduce the subsequent local tumor recurrence, it is critical that all the measures are in place to find the residual foci of occult microscopic tumor at the time of the initial lumpectomy procedure. An accepted method to evaluate the lumpectomy margins for presence of residual tumor is the use of imprint cytology (also called touch-prep), which is assessment of the presence or absence of the tumor cells by cytological preparation. This is a rapid, cost effective, and easy to use procedure with added advantage of saving tissue for permanent sectioning and rendering a definitive diagnosis. In this report, we present our experience using intraoperative imprint cytology for evaluation of the status of lumpectomy specimens in breast cancer patients. The objective of this study was to evaluate the diagnostic accuracy of intraoperative imprint cytology for assessment of surgical resection margins in lumpectomy margins of patients with breast carcinoma. This is a retrospective study of 100 cases of breast lumpectomy specimens, which had undergone intraoperative imprint cytology. The cases were retrieved from the archived files of the University of Florida, Department of Pathology at Shands Jacksonville. The results of intraoperative imprint cytology were compared with the histological findings of the corresponding permanent sections of the same cases as the gold standard. Overall, we reviewed 510 cytology imprint slides, which were obtained from 100 lumpectomy specimens. Among these cases, 37 slides from 22 cases were reported positive and the remaining were negative. Only eight slides from six cases of lumpectomy showed discrepancy between the result of intraoperative imprint cytology and the permanent sections of the same cases. In our study, intraoperative imprint cytology showed a sensitivity of 97%, specificity of 99%, with positive predictive value of 84%, and negative predictive value of 99%. This study demonstrates that intraoperative imprint cytology can be used as a reliable diagnostic procedure for the evaluation of the status of lumpectomy margins in breast cancer patients.