Boldface font indicates statistical significance (P < .05).

Number of cases with information enabling evaluation of EFS.

For the multivariate model, all factors were included that were of significance (P < .05) or borderline significance (P < .10) in univariate or age-adjusted analyses (PD-1, PD-L1, age, stage, WBC count, hemoglobin, albumin, bulky tumor, B symptoms, and extranodal involvement). Also, nodular sclerosis histology, EBV status, lymphocyte count, male sex, and country (Denmark/Sweden) were included because the distribution of these variables differed between high and low PD-L1 (Table 1). Male sex was also added to the multivariate model.

Proportion of positive leukocytes.

Not applicable.

Not tested.