Chemotherapy is a major tool in the fight against cancer. Millions get chemotherapy for their cancer and it can be confusing. This site tries to explain the kinds of chemotherapy, what they do, and how they are administered.
Oncology is the branch of medicine concerned with the nature and treatment of cancer. Oncologists are doctors that specialize in treating cancer patients, and some nurses are specially trained in cancer care.
The three classic “modes” of cancer treatment are surgery, radiation, and chemotherapy. Sometimes the terms “surgical oncology” and “radiation oncology” are used to refer to subspecialties devoted to those forms of treatment. “Medical oncology” is the branch concerned with chemotherapy treatment. Most oncologists do not specialize that much, and will oversee a treatment regimen involving more than one mode. “Multimodality treatment” is the use of more than one mode on a patient.
Chemotherapy drugs are also called antineoplastic drugs, meaning they work against neoplasms (tumors) and often classified as cytotoxic drugs. “Cytotoxic” means they kill cells, which is one reason chemotherapy has such severe side effects. Not all chemotherapy drugs are cytotoxic; many of the new kinase inhibitors are not cytotoxic.
Chemotherapy agents are prescription drugs. Any doctor can prescribe them but typically only oncologists do so. Unlike most prescription drugs you might take, oncology drugs are typically not carried by pharmacies. They are not sold at the retail level. Instead, they are sold wholesale to clinics and hospitals and treatment centers that in turn sell them to the patient (and bill the patient’s insurance company.)
Each patient gets prescribed a regimen that outlines the type, dosage, and schedule for chemotherapy administration. Most often chemotherapy is given in a “course” of several weeks.
Systemic Therapy for Cancer
Cancer is a systemic disease – just like the flu. Many cancers stay local. Either the body’s immune system or medical intervention prevents them from spreading broadly. Experts estimate 50% of discovered (diagnosed) cancers spread so far they are considered metastatic. Surgery and radiation are impractical for addressing distributed cancer. Systemic therapy, including most methods of administering chemotherapy, work throughout the body, and are thus more appropriate for treating widespread cancer.
Forms of systemic therapies for cancer include
- Traditional chemotherapy drugs
- Targeted chemotherapy
- Hormonal therapies
- Biologic therapies