Maintenance Chemotherapy
Doctors have long employed maintenance therapy in management of cancer cases. There are different regimens, but maintenance therapy is almost always milder and less stressful on the body than first-line chemotherapy, if only because the dosages are lower. The idea is to prevent cancer from reappearing – to stop undetectable tumors from growing. And with the introduction of targeted therapy medicines with low side effects, the cost-benefit calculation for maintenance therapy becomes more favorable. Studies have shown maintenance therapy can extend life spans for patients who have had some cancers.
Maintenance chemo stands in contrast to consolidation chemotherapy. Consolidation chemo, which is often the intent behind adjuvant chemo, is a stronger dose that the doctor hopes will wipe out any remaining malignant cells.
The timeframe for maintenance therapy is up to the oncologist, patient, and insurance company. There are no professional guidelines and therapy may last only a couple months or several years.
For patients with advanced cancer in which primary chemotherapy treatment has not resulted in a remission, maintenance therapy can sometimes help extend lifespan. It also can alleviate symptoms, in which case it is palliative chemotherapy.
When a patient’s maintenance therapy is similar in nature to the primary therapy (but at lower doses) it can be called continuation maintenance. When different medicines are used it is called switch maintenance.
Hormone therapy given after primary treatment could be considered maintenance therapy.
Increasing popularity
An increasing fraction of cancer patients have been put on maintenance therapy during the past decade or so for two reasons
- More are surviving primary treatment. Although gains in cancer treatment come slowly, there is progress, and a greater percentage of patients is making it through first-line treatment with a good prognosis.
- The new targeted therapies have fewer and/or milder side effects.
Leukemia has long been treated with maintenance therapy for a long time. It usually lasts two to three years for blood cancer patients. Lung cancer patients are increasingly being put on maintenance therapy with a combination of pemetrexed and erlotinib.
Maintenance intravesical therapy has become the standard treatment for one form of bladder cancer.
The opposite of a drug holiday
For patients with poor prognosis, for whom the cancer is not expected to go into remission, maintenance therapy between periods of intense chemo is an option. Suppose a doctor administers first-line therapy, then stops to evaluate progress and to allow the patient a breather. Even if a second-line therapy is intended, there is an interim period. This time could be filled with a drug holiday. Or it could be used for maintenance therapy.
Sources: https://www.cancer.net/navigating-cancer-care/how-cancer-treated/understanding-maintenance-therapy
https://acsjournals.onlinelibrary.wiley.com/doi/full/10.1002/cncr.24563