Measurement of CK19 mRNA expression intraoperatively can be used as a rapid diagnostic method to detect lymph node metastases in women with breast cancer, according to a report in the June 1st issue of the International Journal of Cancer.
The cytoskeleton protein CK19 is expressed by virtually all breast cancers, the authors explain, and one-step nucleic acid amplification (OSNA) can be used to quantitate CK19 mRNA expression in lymph node samples within 30 to 40 minutes.
Dr. Chris J. L. M. Meijer from VU Medical Center Amsterdam, the Netherlands, and colleagues tested the performance of OSNA for CK19 mRNA in comparison with standard histological methods for identifying lymph node metastases in 346 axillary lymph nodes from 32 Dutch breast cancer patients undergoing axillary lymph node dissection.
OSNA and histology results were concordant for 267 negative samples and 61 positive samples, the authors report, while 18 results were discordant.
In 7 of the 18 discordant samples, sampling bias was thought to account for the disparate results. Excluding these 7 samples, OSNA-CK19 mRNA determination was 95.3% sensitive and 97.1% specific for identifying lymph node metastases.
"The OSNA method based on CK19 mRNA as described in our study is an attractive intraoperative tool for the detection of lymph node metastases in breast cancer patients," the researchers conclude.
"Intraoperative use of OSNA may spare a patient from the discomfort and complications of a second surgical intervention," Dr. Meijer and colleagues explain. "Additional studies, including intraoperative OSNA analyses of sentinel lymph nodes, are currently underway."
Int J Cancer 2008;122:2562-2567.
Reviewed by Ramaz Mitaishvili, MD
