Covering the Chemotherapy Basics
Chemotherapy, administered under the direction of a medical oncologist with assistance from angels otherwise known as chemo nurses, covers a wide range of drug regimens that all produce side effects. Most people undergoing chemotherapy do have to alter some aspects of their lives to accommodate the treatments and the side effects, though many people continue to work and carry out most of their family responsibilities. For a number of reasons — chiefly the possibility of an improved outcome — some people even opt to undergo chemotherapy and radiation therapy at the same time, if both are indicated.
Your chemotherapy treatments are scheduled in cycles, maybe every three or four weeks, with time in between for your body to recover. How many different treatments will be required depends on several factors. Among them are
- The kind of cancer
- The kind of drugs used
- Your age
- Your general health
- Your body's response to the drugs
That last factor, of course, is monitored by your medical oncologist. If you do well, your series of chemotherapy treatments will take place one after another, following logically from the first to the last. However, if chemotherapy is particularly tough for you, your doctor may spread out the treatments, try a different drug or combination of drugs, or perhaps halt chemotherapy altogether.
Sorting out the different drugs
More than 50 different chemotherapy drugs are available to treat cancer. All of them kill cancer cells, though they work in different ways. Generally speaking, all the drugs are designed to go after chemical substances within cancer cells and to interfere with cellular activity during specific phases of the cells' growth cycles. In the process, chemotherapy drugs also kill healthy cells, and that's why side effects develop. Of course, not all drugs work well for all cancers, and in many cases, a combination of chemotherapy drugs is the best course of treatment.
If you're the type of person who wants the details about the treatment you'll be receiving, you can get started here. Researchers have divided the available chemotherapy drugs into categories based on how they work. Here are some of the different types of drugs used, the kinds of cancer they are used to treat, and some of the drug names:
- Antibody-based therapies: These new agents are aimed at molecular targets. These are truly the magic bullets of oncology because they hone in on cancer cells, sparing most normal cells. Currently, antibody-based agents are used to treat breast cancer, colon cancer, lung cancer, lymphoma, and several types of leukemia, but additional targeted therapies are being developed. Ultimately, many other cancers will likely be treated with antibody-based therapies as well. Some of the drugs in use now include trastuzumab, bevacizumab, cetuximab, gefitinib, imatinib, rituximab, and erlotinib.
- Alkylating agents: These anticancer drugs act directly on a cell's DNA, which prevents further cell division. Alkylating agents are used against chronic leukemia; non-Hodgkin's lymphoma; Hodgkin's disease; multiple myeloma; and some cancers of the lung, breast, and ovary. Some of the drugs in use are chlorambucil, cyclophosphamide, cisplatin, carboplatin, thiotepa, and busulfan.
- Nitrosoureas: These drugs act in a way similar to alkylating agents, interfering with enzymes that help repair DNA. Nitrosoureas are used to treat brain tumors, non-Hodgkin's lymphoma, multiple myeloma, and malignant melanoma. Some of the drugs in use are carmustine and lomustine.
- Antimetabolites: These drugs alter the function of enzymes required for cell metabolism and protein synthesis, starving the cells to death. Antimetabolites are used in cases of acute and chronic leukemia and tumors of the breast, ovary, and gastrointestinal tract. Some of the drugs in use are 5-fluorouracil, capecitabine, methotrexate, gemcitabine, cytarabine, and fludarabine.
- Antitumor antibiotics: These drugs bind with DNA and prevent the synthesis of ribonucleic acid (RNA), which is imperative for cell survival. Antitumor antibiotics are used to treat many different cancers. Some of the drugs in use are dactinomycin, daunorubicin, doxorubicin, epirubicin, idarubicin, and mitoxantrone.
- Mitotic inhibitors: These drugs, derived from plants, halt cell reproduction by inhibiting cell division and prohibiting the use of certain proteins required for mitosis. Mitotic inhibitors are used to treat leukemia, lymphomas, and lung and breast cancers. Some of the drugs in use are paclitaxel, docetaxel, vinblastine, vincristine, and vinorelbine.
In some circumstances, corticosteroids, or natural hormones and hormone-like drugs, also are used to treat such cancers as lymphoma, leukemia, and multiple myeloma. Some of the drugs in use are prednisone and dexamethasone. Do these sound familiar? In the past, your doctor may have prescribed corticosteroids for you for conditions or illnesses entirely unrelated to cancer, but the dosages were much smaller and the course of treatment much shorter. Some additional chemotherapy drugs that do not fit into any of the listed categories also are available.
Taking heart from new developments
Every day, cancer research moves forward. Here are just a few new developments.
Introducing new drugs
New chemotherapy drugs are being introduced all the time. Of course, all new treatments undergo years of research and testing before the Food and Drug Administration (FDA) releases them for public use. This testing period allows scientists to determine if the drugs work, if they work better than treatments already in use, and if they are safe. Drugs waiting for approval, drugs that are considered experimental, are tested in clinical trials.
Changing the course of treatment
Other new developments include pairing established drugs with new drugs for a better outcome and administering chemotherapy drugs on a different timetable. Sometimes when the schedule of treatment is altered, the effectiveness of the drug is improved. For that reason, even after chemotherapy drugs are approved by the FDA, the schedule and manner in which the drugs are delivered are explored in clinical trials so the effectiveness of the chemotherapy can be further improved.