CHAPEL HILL -- A new study has identified three subtypes of non-small-cell lung cancer tumors, a finding that may provide valuable clinical information about patient survival in early- or late-stage disease, how likely the cancer is to spread and whether the tumor will prove resistant to chemotherapy.
A report of the study, led by researchers at the University of North Carolina at Chapel Hill's Lineberger Comprehensive Cancer Center, appears in the November issue of the Journal of Clinical Oncology.
Currently, lung cancer treatment decisions are based largely on the location and size of the tumor and if it has spread, or metastasized. And, lung tumor cells are diagnosed by their appearance under a microscope. About 20 percent of these tumors are classified as small-cell carcinomas; the rest fall into a catch-all diagnosis, non-small-cell carcinoma (NSCLC), for which therapies often lead to unpredictable results.
"We are frequently surprised with the range of responses that our patients' non-small-cell carcinomas have. Some are very responsive to treatment, some metastasize early, and we have no way of sorting this out up front," said study lead author Dr. David Neil Hayes, assistant professor of medicine in the division of hematology/oncology in UNC's School of Medicine. To that end, Hayes and his colleagues used a relatively new technology, DNA microarray analysis, which allows researchers to identify a tumor's genetic pattern.
"We found that among patients who have tumors that look similar under a microscope there are dramatically different gene expression patterns," Hayes said. "But what's more interesting is that we see evidence that these genetic patterns are associated with significant differences in tumor behavior, which could not be anticipated by any conventional testing method."
The tumor subtypes, named bronchioid, squamoid and magnoid, according to their genetic pattern, also correlated with clinica
Contact: L. H. Lang
University of North Carolina School of Medicine