Study Incorporates Circulating Tumor Fragments Into Rectal Cancer Treatment Response Models

Researchers at Fudan University Shanghai and other centers in China consider prognostic clues provided by circulating cell-free tumor DNA (ctDNA) fragments in individuals with locally advanced rectal cancer, particularly when it comes to determining which patients can safely forego surgery after neoadjuvant chemotherapy. As reported in Clinical Chemistry, the team used cell-free circulating DNA fragment profiles, 5'-end motif profiles, and magnetic resonance imaging tumor regression grade data for 103 locally advanced rectal cancer patients to develop and validate computational models aimed at predicting which patients do or do not show a pathological complete response to neoadjuvant chemotherapy — a treatment response sought for the surgery-free "watch and wait" approach. The authors conclude that their study supports the combination of a 5'-end motif with magnetic resonance imaging tumor regression grade has promising clinical usage for predicting the tumor response to neoadjuvant chemotherapy in locally advanced rectal cancer patients, further noting that their findings need to be validated independently and on a larger scale.