When a patient with cancer responds well to chemotherapy, he or she may be able to stop taking the anticancer drugs. Sometimes, however, the doctor recommends continuing with a low level of more chemotherapy drugs for some time, after the cancer goes into remission. This type of treatment, which aims to prevent the cancer returning, is called maintenance chemotherapy. As chemotherapy responses differ, maintenance chemotherapy does not appear to be beneficial for all cancer patients and may instead affect quality of life and expose patients to unnecessary risks. Maintenance chemotherapy does not appear to be effective for many cancers, but specific forms of leukemia respond best.
Chemotherapy describes a regime of drugs that can potentially treat and even reverse cancer growth. Various forms of chemotherapy drugs exist, and they all carry side effects. These range from the unpleasant, such as vomiting and hair loss, to dangerous, like an increased risk of infection. Due to the side effects, many cancer patients are happy to stop taking chemotherapy when their cancer goes into remission.
Early versions of chemotherapy drugs were more toxic and had more severe side effects than some of the newest versions. The traditional approach to chemotherapy was that once the patient's cancer went into remission, he or she could stop taking the drugs, and go back to a normal quality of life. As the newer drugs pose less of a risk to health and quality of life than the older versions, the potential risk to the patient may be less, and the patient may therefore be more amenable to maintenance chemotherapy.
Despite the newer drugs being more tolerated than the older drugs, the concept of maintenance therapy is not suitable for many cancers. This is because research into the effectiveness of taking a long course of drugs after the initial, successful chemotherapy, tells doctors that, in most cases, the maintenance therapy does not prevent cancers returning. Most cancers appear to fall into this group, where patients gain no benefit from maintenance chemotherapy.
Acute lymphocytic leukemia and acute promyelocytic leukemia are the exceptions to the rule. People with one of these cancers may reduce their chance of the cancer returning if they take maintenance drugs. Research results prove that the therapy helps people live longer and have longer periods of remission than people who do not take the maintenance.
Evidence in favor of maintenance therapy for other cancers, as of 2011, does not indicate that the therapy is helpful for patients in general. The problem with cancer treatment, however, is that individual people have different biological responses to cancers, and resulting in varying responses to treatments. Research is ongoing, therefore, into which people need maintenance drugs, and which people will not respond to the treatment.