Approximately 80% of lung cancers are of the non-small cell (NSCLC) type and these can be differentiated further, i.e. squamous or non-squamous histology. One of the challenges facing oncologists is that up to a third of squamous cell carcinomas are misclassified, which is important because increasingly, different treatments may be selected depending upon the histology.
An interesting study that may address this issue has just been e-published in the Journal of Clinical Oncology by researchers from NYU Langone Medical Center at New York University School of Medicine. In it, they reported that a microRNA-based diagnostic test can objectively identify squamous lung cancer with 96% sensitivity.
Squamous lung cancer carries increased risk of severe or fatal bleeding from vascular endothelial growth factor receptor (VEGF) inhibitors such as bevacizumab (Avastin) and other similar drugs in development. In addition, other approved therapies such as pemetrexed (Alimta) are indicated for non-squamous lung cancer only, so accurately defining a patient's histology is crucial.
According to the Institution press release, Dr Harvey Pass, one of the lead investigators reported that:
The test involves use of qRT-PCR assays, a standard process in testing for various cancer markers. While is it likely that most academic institutions will be able to perform the test quickly and easily, use of the assay may take a little while to filter out to the network of community oncologists who treat the vast majority of lung cancer patients in the US and order tests from commercial diagnostic companies.
Lebanony, D., Benjamin, H., Gilad, S., Ezagouri, M., Dov, A., Ashkenazi, K., Gefen, N., Izraeli, S., Rechavi, G., Pass, H., Nonaka, D., Li, J., Spector, Y., Rosenfeld, N., Chajut, A., Cohen, D., Aharonov, R., & Mansukhani, M. (2009). Diagnostic Assay Based on hsa-miR-205 Expression Distinguishes Squamous From Non-Squamous Non-Small-Cell Lung Carcinoma Journal of Clinical Oncology DOI: 10.1200/JCO.2008.19.4134