أ.د. هشام سليمان ابوعوده

Cancer is the uncontrolled growth of cells coupled with malignant behavior: invasion and metastasis. Cancer is thought to be caused by the interaction between genetic susceptibility and environmental toxins. Chemotherapy is the use of chemical substances to treat disease. In its modern-day use, it refers to cytotoxic drugs used to treat cancer or the combination of these drugs into a standardized treatment regimen. Broadly, most chemotherapeutic drugs work by impairing mitosis (cell division), effectively targeting fast-dividing cells. As these drugs cause damage to cells they are termed cytotoxic. Some drugs cause cells to undergo apoptosis (so-called "programmed cell death"). As chemotherapy affects cell division, tumours with high growth fractions (such as acute myelogenous leukemia and the aggressive lymphomas, including Hodgkin's disease) are more sensitive to chemotherapy, as a larger proportion of the targeted cells are undergoing cell division at any time. Malignancies with slower growth rates, such as indolent lymphomas, tend to respond to chemotherapy much more modestly.