For cases with relapsed/refractory cHL (R/R cHL), the NCCN Guidelines recommend second‐line systemic therapy regimens, such as brentuximab vedotin (BV), programmed cell death 1 (PD‐1) blockade therapy, chemotherapy, and their combinations, or radiotherapy, followed by autologous stem cell transplantation (ASCT) [5]. The gene discussed is PDCD1; the disease is classic Hodgkin lymphoma.