NCCN Guidelines for Patients® | Myelodysplastic Syndromes
31 NCCN Guidelines for Patients ® : Myelodysplastic Syndromes, 2018 4 Cancer treatments Chemotherapy Chemotherapy Chemotherapy is the use of drugs to destroy abnormal cells in the body. But, the drugs can also affect normal cells. Many people refer to this treatment as “chemo.” Different types of chemotherapy drugs work in different ways to kill abnormal cells or stop new ones from being made. Thus, more than one drug may be used. When only one drug is used, it’s called a single agent. A combination regimen is the use of two or more chemotherapy drugs. Chemotherapy is given in cycles of treatment days followed by days of rest. This allows the body to recover before the next cycle. Cycles vary in length depending on which drugs are used. The number of treatment days per cycle and the total number of cycles given also varies. Some chemotherapy drugs are liquids that are injected into a vein or under the skin with a needle. Other chemotherapy drugs may be given as a pill that is swallowed. The main chemotherapy drugs used for MDS are described next. Guide 4 on page 32 lists chemotherapy drugs and other drugs used to treat MDS. Low-intensity chemotherapy Low-intensity chemotherapy is treatment with drugs that are less likely to cause severe side effects. These drugs are often given in an outpatient setting—this means that you don’t have to spend the night in the hospital. There are two low-intensity chemo drugs approved to treat MDS: Azacitidine (Vidaza ® ) Decitabine (Dacogen ® ) These drugs are a type of chemotherapy called hypomethylating agents. They work by blocking DNA that helps abnormal cells grow. This helps to “turn on” genes that promote the growth of normal, healthy cells in the bone marrow. Azacitidine is a liquid that is injected into a vein or under the skin. A treatment cycle often consists of 7 days of treatment followed by 21 days of rest. At least 4 to 6 cycles should be given before this medication is declared to have failed. It is usually hard to tell if the drug is working before 4 to 6 cycles have been given; a bone marrow biopsy should be done at least every 4 to 6 months to assess the response to treatment. If treatment works well, cycles may repeat on a monthly basis until it stops working. Even if you have a complete response to treatment, your doctor may continue to give you cycles of medication. Decitabine is a liquid that is slowly injected into a vein. This is called an IV ( i ntra v enous) infusion. The IV infusion takes 1 hour and must be given in a hospital or clinic. The 1-hour infusion is given once a day for 5 days in a row. This is repeated every 4 weeks. At least 4 to 6 cycles should be given before the drug is assessed for activity with a bone marrow biopsy. If treatment works well, cycles may repeat until it stops working. High-intensity chemotherapy High-intensity chemotherapy is treatment with high doses of strong drugs that are more likely to cause severe side effects. High-intensity chemo includes drugs and regimens that are used to treat AML. These drugs work in different ways to kill unhealthy cells in your blood and bone marrow, and work well against fast-growing cells. But, they are very toxic and kill normal cells along with cancer cells. Thus, doctors prefer these drugs be given in a clinical trial or before an HCT ( h ematopoietic c ell t ransplant) for treatment of MDS. See page 35 to learn more about an HCT.