Maintenance Therapies in Indolent Lymphomas: should Recent Data Change the Standard of Care?

OPINION STATEMENT: The overall benefit of maintenance therapy for patients with an indolent lymphoma continues to go unanswered. A myriad of variables contribute to the lack of clear clinical guidance. First, the disease course is slow and treatment may not be required for years, requiring a long follow-up to prospectively study. Second, due to the long lag time from study initiation to conclusion, many of the induction therapies used at the onset of the study may not be favored at present, providing a conclusion that cannot be reconciled with current clinical practice. For example, bendamustine and rituximab are typically the favored initial treatment agents in follicular lymphoma, which was not true when many maintenance trials were initiated. Third, several studies' inclusion criteria allow for patient enrollment at both initial diagnosis as well as at disease recurrence. In some studies, patients who are asymptomatic are started on therapy, counter to the accepted watch and wait approach. This contributes to the difficulty of generalizing results. The question of the benefit of maintenance therapy has been studied enough, and there may not be a smoking gun in the foreseeable future. However, what does hold promise is focusing on the patients with minimum residual disease after conclusion of chemotherapy. This may be a population that could receive benefit from a prolonged treatment approach. In the meantime, maintenance therapy should not be used in all patients, and the rationale for use should be data-driven, as well as an assessment of a patient's potential intolerability of cytotoxic chemotherapy.