What Is AC Chemotherapy?

AC chemotherapy is a medical procedure used in the treatment of cancer. It works through the intravenous injection of the drugs doxorubicin (C₂₇H₂₉NO₁₁) and cyclophosphamide (C₇H₁₅C_l2N₂O₂P), which slow or stop the growth of malignant cells. The letters “AC” come from adriamycin, the trade name for doxorubicin, and cytoxan, one of the trade names for cyclophosphamide. AC chemotherapy is commonly used for patients with breast cancer.

The properties of both drugs used in AC chemotherapy work together to stop the progression of cancerous cells. Doxorubicin is an antibiotic that interferes with the biosynthesis of large molecules, and doxorubicin molecules can disrupt the functioning of DNA by fitting themselves between DNA base pairs in a process called DNA intercalation. Its presence inhibits an enzyme called topoisomerase II that is important for the transcription and replication of DNA, preventing cancerous cells from reproducing.

Cyclophosphamide is a type of compound called an alkylating agent. This means that it can transfer a group of single-bonded carbon and hydrogen atoms called an alkyl group to other molecules. Cyclophosphamide in the body is metabolized in the liver into the metabolites acrolein (C₃H₄O) and phosphoramide mustard (C₄H₁₁C_l2N₂O₂P). The phosphoramide mustard then reacts with DNA in cancerous cells, producing cross-linkages between different points within or between DNA strands. This makes it impossible for the DNA to replicate and eventually kills the cell.

The drugs used in AC chemotherapy are given to patients intravenously through a tube inserted into the hand, arm, or collarbone. This usually takes an hour or two, along with additional time for blood testing. This procedure is repeated every three weeks for a period of three to four months, with the entire process usually consisting of four to six treatments.

Cancerous cells are vulnerable to chemotherapy because chemotherapy drugs disrupt cell division, and because cancer is the result of out-of-control cell growth and replication, malignant cells are more likely than healthy cells to be in the process of dividing at any particular time. Nevertheless, the drugs used have a negative effect on normal cells as well as cancerous cells, and so AC chemotherapy can have a number of side effects. These can include hair loss, nausea, and sores on lips or inside the mouth, as well as weakening the immune system and increasing susceptibility to infection. In some cases, the treatment also causes infertility and impaired short-term memory, which may linger after treatment is concluded.