[Preventable side effects of chemotherapy]

During the last years antineoplastic chemotherapy provided the possibility to cure many patients suffering from a malignant tumor and to improve their quality of life. Like every powerful remedy cytostatic drugs show side effects, which must be taken into consideration. Advantages and risks of cancer chemotherapy have to be considered carefully in each individual treatment schedule. The definition of the upper limit of therapeutic risk for each individual patient in order to avoid life-threatening situations is of principal importance. This can be accomplished by introduction of methods which can measure actual functional conditions and by the definition of a threshold-level in order to establish contraindication. Paul Ehrlich introduced the term "therapeutic index" in antibacterial chemotherapy. This term should express the ratio between risk and benefit of a drug and its application in the still very young field of antineoplastic chemotherapy should be considered. Since every treatment of a patient with cytostatic drugs represents a very significant interference with the patient's life, very strict indication- and and contraindication-criteria have to be applied.