Circulating Tumor DNA Predicts Colorectal Cancer Relapse

Circulating tumor DNA detected through liquid biopsy is an independent predictor of patients with colorectal cancer (CRC) who are likely to relapse after surgery, according to research presented at the ESMO Congress 2019.

The prospective, phase III IDEA-FRANCE trial included 805 patients who had a liquid biopsy prior to adjuvant chemotherapy for stage III CRC, of whom 109 (13.5%) had circulating tumor DNA in their blood.

Circulating tumor DNA affects survival, response to adjuvant treatment

Two-year disease-free survival was 64% among those who were circulating tumor DNA-positive versus 82% in those who were circulating tumor DNA-negative (hazard ratio [HR] = 1.75; 95% CI, 1.25-2.45).

The study also showed that six months of adjuvant treatment was superior to three months of therapy in both circulating tumor DNA-positive and -negative patients. Most patients (90%) received FOLFOX (folinic acid, fluorouracil, and oxaliplatin) as adjuvant therapy.

The results showed that post-surgical plasma circulating tumor DNA predicted metastatic relapse a median of 10 months before recurrence was visible on radiological scans (HR=11.33; P=0.0001). The researchers concluded that plasma circulating tumor DNA testing offers an opportunity for precision treatment of patients with localized CRC.