Theoretically, elevated IL‐6 was likely to contribute to immune evasion and disease relapse after anti‐PD‐1 therapy; investigation of single‐cell landscape of cHL is required and under way, in order to clarify the detailed mechanism underlying the effective antitumor response and resistance to epi‐immunotherapy in patients with relapsed/refractory cHL. This evidence concerns the gene IL6 and classic Hodgkin lymphoma.