Treating Hodgkin lymphoma in the new millennium: Relapsed and refractory disease.

Although the majority of patients with Hodgkin lymphoma are cured with initial therapy, 10% to 15% of patients with early stage disease and 15% to 30% of patients with advanced disease have primary refractory or relapsed lymphoma. For younger patients whose disease is sensitive to second-line therapy, more than half of patients will experience long-term disease control with high-dose chemotherapy/autologous stem cell rescue (ASCT). For those patients who are chemotherapy refractory, relapse after, or are ineligible for ASCT, brentuximab vedotin, and checkpoint, inhibitors are highly active, although the majority of patients will ultimately experience recurrent lymphoma. Allogeneic transplant is curative in a subset of patients but may be associated with significant toxicity. Novel targeted and immunotherapy approaches, including chimeric antigen receptor T-cell therapy, are currently being studied in clinical trials with promising early results.