Chemotherapy drugs are administered:
- as a pill (orally)
- directly into a body cavity (sometimes peritoneal mesothelioma is treated this way)
- injected into the muscle or fat tissue
- intravenously (directly to the bloodstream) (both Alimta and alkylating agents such as cisplatin and carboplatin are administered this way)
- topically (applied to the skin)
Over the years a large number of different treatments such as radiation therapy and surgical processes have been developed to treat different types of cancers. Chemotherapy is often combined with other modalities to make cancer treatment more effective.
The main objective of chemotherapy is to destroy the cancerous cells while minimizing damage to the healthy cells. Scientists try to come up with the best drugs by identifying characteristics that are unique to cancerous cells and absent from normal cells. One of the features that chemotherapy agents often target is the fast multiplying nature of cancer cells.
The Cell Cycle
For better understanding of how chemotherapy works, it is important to have a basic idea of the cell cycle. The cell cycle is a sequence of events that occur when a cell duplicates itself and divides in two. The cycle occurs in fours phases- G1, S (Synthesis), G2, and M (Mitosis).
DNA replication occurs during the S phase. RNA and small amount of protein is developed during the G2 phase. Actual nuclear and cytoplasmic cell division occurs during the M phase. Most of the protein synthesis occurs during the G1 phase and because during this phase DNA is coiled tightly, it is not actively transcribed or copied.
Glossary of some chemotherapy terms