1. ¹Department of Surgery and Surgical Oncology Laboratory, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
2. ²Klinische Onkologie im NCT, Universitätsklinikum Heidelberg, Heidelberg, Germany
3. ³Department of Pathology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
4. ⁴Department of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
5. ⁵The Ludwig Institute for Cancer Research, New York Branch, New York, NY, USA
6. ⁶The Goldyne Savad Institute of Gene Therapy, Hadassah-Hebrew University Medical Center, Jerusalem, Israel

Correspondence: Dr A Nissan, Department of Surgery, Hadassah-Hebrew University Hospital Mount Scopus, PO Box 24035, Jerusalem, Israel. E-mail: anissan@hadassah.org.il

Received 31 October 2005; Revised 12 January 2006; Accepted 17 January 2006; Published online 21 February 2006.

Abstract

The presence of metastases in lymph nodes is the most powerful prognostic factor in breast cancer patients. Routine histological examination of lymph nodes has limited sensitivity for the detection of breast cancer metastases. The aim of the present study was to develop a multimarker reverse transcriptase–polymerase chain reaction (RT—PCR) assay for the detection of minimal residual disease in sentinel nodes of breast cancer patients. RNA was extracted from 30 sentinel lymph nodes (SLN) obtained from 28 patients, three primary breast cancers (positive controls), three lymph nodes from patients with benign diseases, and peripheral blood lymphocytes of 10 healthy volunteers (negative controls). RT–PCR was performed using the following markers; cytokeratin (CK)-19, NY-BR-1 and mammaglobin B. RT–PCR results were compared to enhanced histopathologic examination and immunohistochemistry (IHC). All three positive controls showed strong PCR amplification for all three markers. None of the 13 negative controls was amplified by any of the three markers. Among the 30 SLN analysed, breast cancer metastases were detected in six SLNs by routine histology, in eight by IHC and in 15 by RT–PCR. We conclude that a multimarker RT–PCR assay probing for NY-BR-1, mammaglobin-B, and CK-19 is more sensitive compared to enhanced pathologic examination. This method may prove to be of value in breast cancer staging and prognosis evaluation.