Molecular Diagnostics in NSCLC with David Berz, MD, PhD, and Philip Bonomi, MD - Episode 4
How might mutational results with a liquid biopsy (based on circulating tumor DNA) differ from those obtained through traditional tissue biopsy methods?
BERZ:Although somatic mutations are felt to happen on the tissue base, liquid biopsies allow for certain advantages. One of which being our understanding that many tumors, including lung cancers, are highly heterogeneous. Not only can histologies like squamous cell biology and adenocarcinomas coexist within the same tumor volume, there is also a strong degree of molecular heterogeneity identified in those tumors. The liquid biopsy allows for a more comprehensive molecular assessment of the entirety of the tumor burden in any given patient.
BONOMI:The other aspect of that is that you may have a fairly sizable mass, but not much tumor cellularity. A tumor could be mostly inflammatory cells and stroma. So in a regular biopsy, putting needles in and getting a lot of cores would not be beneficial for diagnosis. In contrast, a liquid biopsy is likely to show DNA circulating in the blood and you will be able to determine mutations, due to having more information available..
Naoko T. is a 74-year-old retired high school teacher originally from Nagoya, Japan. She currently lives in San Diego, California and enjoys tennis and traveling with her husband.
In November 2014, after several months of stable disease, the patient returns for follow-up visit with worsening back pain, and her CT scan is consistent with progression of metastatic lesions.
At this point, the patient declined further treatment, and by March 2015, she returned with worsening dyspnea and declining performance status