(HealthDay News) — Patients with acute myeloid leukemia whose peripheral blood blasts clear in six days or less after chemotherapy have significantly better survival than patients whose peripheral blasts clear later, according to a study published in the Nov. 1 issue of Cancer.
Martha Arellano, M.D., from Emory University in Atlanta, and colleagues investigated the association between time to peripheral blood blast clearance after induction chemotherapy and disease status in 162 patients with acute myeloid leukemia.
The researchers found that, 14 days after induction chemotherapy, marrow blast clearance was observed in 84 percent of 119 patients with early peripheral clearance (six days or less) and 60 percent of 43 patients with delayed peripheral clearance (greater than six days). After a median follow-up of 1,538 days, the early clearance group had significantly longer relapse-free survival (442 versus 202 days) and overall survival (930 versus 429 days). After controlling for multiple variables, early peripheral blast clearance was a significant predictor of marrow blast clearance at day 14, remission, and relapse-free and overall survival.
“Early clearance of peripheral blood blasts after induction chemotherapy predicts for early marrow blast clearance, complete remission, relapse-free survival, and overall survival,” Arellano and colleagues conclude. “Early blood blast clearance provides reassuring information to patients early into the course of their therapy and prior to the availability of cytogenetic and molecular markers, given the association with better relapse-free survival and overall survival.”