Systematic review and meta-analysis on the prognostic value of complete remission status at FDG-PET in Hodgkin lymphoma after completion of first-line therapy

This study aimed to systematically review and meta-analyze the prognostic value of complete remission status at (18)F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in Hodgkin lymphoma after completion of first-line therapy. A systematic literature search was performed in the MEDLINE database for suitable original articles. The included studies were methodologically assessed using the Quality In Prognosis Studies tool. The proportion of patients who developed disease relapse during follow-up, among those patients who were in complete remission according to FDG-PET at the completion of first-line therapy, was calculated for each included study. Heterogeneity in disease relapse proportions across individual studies was assessed using the I(2) statistic, with heterogeneity regarded present if I(2) < 50 %. Weighted summary disease relapse proportion was calculated using either a random effects model (if I(2) > 50) or a fixed effects model (if I(2) ≤ 50). Ten studies comprising a total number of 1137 Hodgkin lymphoma patients with complete remission status according to FDG-PET after completion of first-line therapy were included. Overall methodological quality of included studies was reasonably good. The disease relapse rate during follow-up among all patients with complete remission status at end-of-treatment FDG-PET ranged from 0 to 26.7 %, with a weighted summary proportion of 7.5 % (95 % confidence interval 3.9–13.8 %) using the random effects model (I(2) = 88.3 %). In conclusion, although the disease relapse rate in Hodgkin lymphoma patients who achieve an FDG-PET-based complete remission after first-line therapy is low from an absolute point of view, it is actually high when considering the generally favorable outcome of Hodgkin lymphoma.