Dr. Iams on Small Cell Lung Cancer Subtyping in Clinical Practice

Wade T. Iams, MD, assistant professor of medicine, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, discusses the potential for providing small cell lung cancer (SCLC) subtyping in clinical practice.

Current subtyping modalities are largely tumor-based, says Iams. Initial methodology bases classification on characteristic patterns of RNA expression, while more recent systems utilize immunohistochemical analysis of protein expression. Since SCLC tumors are primarily necrotic and patients rarely undergo surgical removal according to the standard of care, there is often a lack of viable tumor tissue for clinicians to study, Iams explains.

However, a recent collaborative study of cell-free DNA (cfDNA) methylome profiling in SCLC featured in Nature Cancer demonstrated that cfDNA assays, including blood tests, could detect SCLC subtypes through the analysis of specific DNA methylation signals. This breakthrough study indicates the potential use of blood-based assays to classify and accordingly treat clinically relevant subgroups of SCLC, Iams concludes.