Traditionally cancer patients were treated by chemotherapy. Chemotherapy targets rapidly dividing cells and therefore unintentionally takes out innocent bystander cells that happen to divide quickly. They do this by inferring with cellular division. This explains the hair loss seen with chemotherapy patients. Hair follicles have rapidly dividing cells that are killed by the chemotherapeutic agent. This also causes gastro intestinal distress which is a common side-effect of chemotherapy.
Chemotherapy agents are often effective at helping slow the growth of a tumor, however the side effects of chemotherapy can be fatal. Even with the known risks of chemotherapy this is often the only choice a patient with cancer has. Chemotherapy is still the most widely used treatment for cancer.
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