A novel genetic assay helps identify patients with early, aggressive lung cancer who might benefit from adjuvant therapy.
The assay provides considerably more prognostic information than do conventional criteria as defining high-risk tumors warranting treatment that was proposed by the National Comprehensive Cancer Network (NCCN; Fort Washington, PA, USA).
The assay results were used to stratify the 269 study patients who had undergone resection of T1a node-negative and nonmetastatic, nonsquamous, non-small-cell lung cancer (NSCLC) into groups with distinctly different five-year survival rates. The novel assay assesses expression of 14 genes involved in lung cancer tumorigenesis, including ones on the epidermal growth factor receptor
(EGFR)and the Kirsten ras oncogene homolog (KRAS) signaling pathways.
The assay is the only lung cancer signature to undergo blinded validation in two large cohorts from different countries, one in the United States of America and one in China. It is marketed as Pervenio Lung RS by Life Technologies (Carlsbad, CA, USA). The main study results, reported showed that the 5-year actuarial overall survival was 83%, 69%, and 52% among patients defined by the assay as low-, medium-, and high-risk groups, respectively. In multivariate analyses, relative to their counterparts in the low-risk group, patients in the intermediate-risk group had a 2.0-fold higher risk of death and patients in the high-risk group had a 3.3-fold higher risk.
The assay, which is a quantitative polymerase chain reaction (qPCR)-based, also showed good risk discrimination in analyses restricted to the smallest of tumors, those measuring 1.5 cm or less and even those measuring 1.0 cm or less. When compared with tumor size alone, the combination of the assay and tumor size significantly improved on the identification of patients who died.
Johannes R. Kratz, MD, the lead author of the study and a postdoctoral fellow at the University of California, San Francisco (CA, USA) said, “Despite the popularity and endorsement of our radiology colleagues for techniques such as stereotactic radiation for small T1aN0M0 tumors (i.e., Stage IA, no adverse features, Breslow ≤ 1 mm, T1a, no ulceration (U-), mitotic rate less than 1 mm2) , we should remember that these techniques don’t provide us with potentially important lung tissue that can provide prognostic and predictive information.” The study data was reported at Annual Meeting of the Society of Thoracic Surgeons, January 26–30, 2013, in Los Angeles (CA. USA).
National Comprehensive Cancer Network
University of California, San Francisco