[Palliative therapy in cancer. 5. Side effects by anticancer drugs and their treatments]

Many chemotherapeutic agents have been evaluated during the last 40 years and some have now an established place in the management of malignant disease. However these agents have a level of toxicity well above any other group of drugs. Chemotherapeutic agents do not discriminate between normal and neoplastic tissue. Chemotherapeutic regimens that are toxic to rapidly dividing malignant cells, are liable to be particularly harmful to lymphoid tissues, bone marrow and the epithelium of the gastrointestinal tract. The side effects due to chemotherapy are classified as immediate, early, delayed and late. Immediate side effects are those that may occur within the first 24 hours of treatment. The most common immediate side effect is nausea and vomiting, due to direct central effect on the vomiting center of the brain. Cisplatin and nitrogen mustard are particularly prone to this complication. The antiemetics usually used are metoclopramide, domperidone and steroid. The efficacies of these drugs are not so good for nausea and vomiting due to cisplatin administration, however several blockades against serotonin M-receptor recently developed are quite effective to nausea and vomiting of chemotherapeutic regimens including cisplatin. Early side effects commence within about one month of therapy. The most common is bone marrow toxicity and can occur after therapy with the vast majority of anticancer drugs. The relative importance of leukopenia and thrombocytopenia vary between the drugs and their route of administration. Recently, hematopoietic cytokines, such as granulocyte-colony stimulating factor (G-CSF) and granulocyte-macrophage-colony stimulating factor (GM-CSP) have been introduced to granulocytopenia developed by cancer chemotherapy. In the phase II study of G-CSF, a rapid recovery of granulocytes after chemotherapy and marked efficacy on infection in granulocytopenic patients were observed. In addition to this, autologous bone marrow transplantation after chemotherapy has been described in patients with solid tumors.