AACR, Author Interviews, Biomarkers, Cancer Research, Colon Cancer / 26.06.2020

MedicalResearch.com Interview with: Guardant HealthVan Morris, M.D. Department of Gastrointestinal Medical Oncology Division of Cancer Medicine MD Anderson Center MedicalResearch.com: What is the background for this study? Response: Stage II colon cancer is diagnosed in approximately 25% of all colon cancer cases.  Oncologists do not have a reliable biomarker to identify patients who do or do benefit from adjuvant chemotherapy for this population of patients.  Circulating tumor DNA is shed by tumor cells as they die and harbors somatic mutations which distinguish its DNA from that of normal cells. Recently, circulating tumor DNA has shown great promise in distinguishing patients with colon cancer (as well as other solid tumors) that do or do not recur after surgery.  Here, patients who have detectable circulating tumor DNA - a surrogate for the presence of microscopic, minimal residual disease – inevitably recur, whereas the likelihood of recurrence is much lower for patients who do not have detectable ctDNA. (more…)
ASCO, Author Interviews, Biomarkers, Melanoma, NYU / 02.06.2019

MedicalResearch.com Interview with: David Polsky, MD, PhD Dermatologist and Director of the Digmented Lesion Service Mahrukh M. Syeda, MS Research Associate Ronald O. Perelman Department of Dermatology NYU Langone Health MedicalResearch.com: What is the background for this study? Response: Several studies of metastatic melanoma patients have demonstrated that measuring circulating tumor DNA (ctDNA) associates with their disease burden and survival.  Generally, patients with detectable pre-treatment ctDNA levels and/or detectable ctDNA at various time intervals after starting treatment have shorter survivals than patients with lower pre-treatment or on-treatment ctDNA levels.  Studies have varied in their methods to detect ctDNA, the thresholds chosen to call a sample positive or negative, and the follow up time point for measurement, if any. In this study, we examined pre-treatment and week 4 on-treatment plasma samples from patients enrolled in Combi-D, the Phase III, randomized, double-blind trial of the BRAF and MEK inhibitors Dabrafenib and Trametinib, which led to FDA approval of the combination therapy for patients with unresectable stage III/IV melanoma. Only patients with BRAF V600E or V600K mutations identified from tumor genotyping were enrolled in the clinical trial. (more…)