Schema of samples from INCAN. Of 670 FFPE biopsy specimens, 60 failed quality control based on expression of housekeeping genes. Among the remaining 610, 11 patients had 2 samples each, and the results from each pair were averaged. The remaining 599 samples (597 patients) consisted of 560 obtained before therapy and 39 after relapse. Two patients had biopsy specimens both before therapy and after relapse; 1 had FL grade 1 to 2 at both time points, and 1 had FL grade 3A before treatment and DLBCL-not otherwise specified (NOS) at relapse. Untreated biopsy specimens were divided into training (n = 397) and validation/testing (n = 163) cohorts.