Chemotherapy was traditionally described as a systemic process of using chemicals (drugs) to kill cancer cells. The body is the system in this systemic process. Drugs are taken orally, injected through a vein or injected in a muscle to reach the entire system. Chemotherapy now involves methods of administering drugs intrapleurally to the chest cavity or intraperitoneally into the abdominal cavity. These processes are not systemic and are used to inject drugs directly in the cancerous areas of the body. Though chemotherapy drugs are successful in killing cancer cells, they may also kill other healthy cells. The type and amount of dugs as well as the length of chemotherapy treatment must be tailored to each individual patient. Chemotherapy may damage blood-producing cells in bone marrow, which causes low blood cell counts and a shortage of blood platelets. A shortage of white blood cells increases the risk of infection. A shortage of red blood cells increases the risk of fatigue and shortness of breath. A shortage of platelets increases the risk of bleeding and bruising from cuts and injury. Chemotherapy may also damage cells in the hair follicles and gastrointestinal system. In an effort to avoid damage to other healthy cells within the body, methods of intrapleural or intraperitoneal chemotherapy are used. These methods allow doctors to increase the amount of dosage used. These methods may also be used to reduce symptoms of mesothelioma that cannot be eliminated or reduced with surgery. Chemotherapy is a palliative, not curative, method of treating mesothelioma that may be used as the primary form of treatment or it may be used in conjunction with surgery. When used in conjunction with surgery, chemotherapy may be used prior to surgery or after surgery is completed to reduce symptoms associated with mesothelioma. When chemotherapy is used prior to surgery, it is described as neoadjuvant chemotherapy. When chemotherapy is used following surgery, it is described as adjuvant chemotherapy. Chemotherapy has been shown to be effective in slowing the growth of pleural mesothelioma. When used for peritoneal chemotherapy, drugs may be heated. This process of administering chemotherapy with heated drugs is described as hyperthermic chemotherapy.  Several different drugs have been used in the process of chemotherapy and it usually includes more than one drug, except when patients are not able to tolerate the combination, in which case, a single drug is used. The combination of drugs may include the following: ·         Pemetrexed (alimta®) and cisplatin·         Cisplatin and gemcitabine (gemzar®)·         Carboplatin and gemcitabine·         Methotrexate and vincristine·         Cisplatin and doxorubicin·         Doxorubicin, cyclophosphamide (ifosfamide) and cisplatin 

When patients are not able to tolerate combinations of drugs, any of the above listed drugs may be used alone. The pemetrexed/cisplatin combination is currently the most preferred combination of drugs. The combination is necessary since alimta interferes with the normal metabolism of folic acid and vitamin B12 and cisplatin is used to avoid side effects. The combination of gemcitabine with cisplatin also offers a very good response rate. The carboplatin/gemcitabine combination also offers a good response rate, but with lesser side effects of vomiting and nausea.

 The side effects of chemotherapy are usually temporary and include loss of appetite, hair loss, mouth sores, nausea and vomiting. These side effects usually disappear after treatment is completed. Other drugs or remedies may be used to prevent or reduce these side effects.