Page 174 - 18F-FDG PET as biomarker in aggressive lymphoma; technical and clinical validation

Chapter 6b
hazard for young versus elderly patients of 0.62, an accrual period of 5 years, and 2 years of follow-up after the last patient was included in the maintenance randomization, this would require 395 patients (young, n = 174; elderly, n = 221). Therefore, 575 patients should be included in this trial, resulting in a power of 86% to detect an improvement in complete remission (CR) rate from 77% to 87%.
Statistical Methods
The primary end point for R1 was CR on induction. Patient treatment was considered a success if CR was achieved during or after induction treatment. All other patient treatments were considered a failure. Logistic regression analysis with adjustment for age group (18-65 v ≥ 66-80 years) and age-adjusted International Prognostic Index (IPI) score (0 v 1 v 2 v 3; categorical) was applied for the primary analysis, and odds ratios and 95% CIs were determined, with P values < .05 considered statistically significant.
Secondary end points were best response on protocol treatment, adverse events, FFS, progression-free survival (PFS) and overall survival (OS) from R1, and disease-free survival (DFS) from CR. FFS was defined as time from R1 to no CR on protocol, relapse, or death, whichever came first. PFS was calculated from R1 to progression, relapse, or death, whichever came first. OS was determined from R1 to death resulting from any cause. Patients still alive at last contact were censored. DFS was measured from date of CR to relapse or death, whichever came first.
arms post hoc using the χ test or Fisher’s exact test, whichever was appropriate.
The proportion of patients with specific adverse events was compared between 2
For the survival end points, the HRs and 95% CIs were determined using univariable and multivariable Cox regression analyses. Multivariable Cox regression analysis was primarily aimed at evaluating the impact of adjustment on the HRs and 95% CIs of treatment arms, rather than at evaluating the prognostic value of individual covariates, and included: treatment arm, age (18-65 v ≥ 66-80 years), sex (male v female), age-adjusted IPI stage (low v low-intermediate v high- intermediate v high; continuous), WHO performance (0 v 1 v 2; continuous), lactate dehydrogenase (normal v elevated), B symptoms (no v yes), bulky mass (no v yes), and bone marrow involvement (no v yes), as specified in the statistical analysis plan. Because the number of patients with missing data was low (ie, 3
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