Reverse transcription-polymerase chain reaction assay for multiple mrna markers in the detection of breast cancer metastases in sentinel lymph nodes

The identification of specific tumor mRNA markers by reverse transcription- polymerase chain reaction might be a valuable diagnostic adjunct for the de tection of breast cancer metastases in axillary sentinel lymph nodes (SLNs) . In this study we have compared the diagnostic accuracy of an extensive hi stopathologic examination of 146 SLNs from 123 breast carcinoma patients wi th that of the evaluation of 5 mRNA markers. When analyzed individually, no ne of the different markers attained a sensitivity higher than 77.8%, and t he general concordance with the histopathologic findings ranged from 78.8 t o 83.6%. In a multiple-marker assay, taking into account the expression of at least 1 of the 5 tumor markers, the sensitivity of the test rose to 95.6 %, with a specificity of 66.3% and a general concordance with the histopath ologic status of 75.3%. Finally, when at least 2 of 3 markers (maspin, cyto keratin 19 and mammaglobin 1) were expressed, the concordance with either S LN or axillary lymph node status was highest (88.4% and 84.6%, respectively ). The high prevalence of positive reverse transcription-polymerase chain r eaction assays in histologically uninvolved SLNs, however, may hamper exten sive application of these techniques in the clinical setting. (C) 2001 Wile y-Liss, Inc.