Cancer is the second leading cause of death in the United States, exceeded only by heart disease.
The American Cancer Society estimates that in 2007 about 1.4 million new cancer cases are expected to be diagnosed and 559,650 cancer deaths are expected to occur in the United States.
Cancer is a heterogeneous group of diseases characterized by uncontrolled cell division and growth resulting in the development of a mass of cells or tumor, as well as the invasion and spreading of these cells to other organs of the body (metastasis). Cancerous tumors can arise in any tissue or organ within the human body and generally cause clinical problems to the patient when the tumor affects the function of that organ or when the tumor spreads to other organs. Cancers which arise in the bone marrow (e.g. acute and chronic leukemias and multiple myeloma) or the lymph nodes (Hodgkin’s disease and lymphomas) spread through the bone marrow and lymphatic systems, affecting the growth of normal blood and lymphatic cells. Cancer is believed to occur as a result of a number of factors, such as genetic predisposition, chemical agents, viruses and radiation. These factors result in genetic changes affecting the ability of cells to regulate their growth and differentiation.
The most common methods of treating patients with cancer are surgery, radiation and anticancer drugs (chemotherapy). A cancer patient often receives treatment with a combination of methods. Surgery and radiation therapy are particularly effective in patients where the disease is localized. The most common method of treating patients with cancer that has spread beyond the primary site is to administer systemic chemotherapy. Chemotherapy seeks to damage and kill cancer cells or to interfere with the molecular and cellular processes that control the development, growth and survival of malignant tumor cells. In many cases, chemotherapy consists of the administration of several different drugs in combination. Chemotherapy can cause a number of side effects in patients, including weakness, low blood count, loss of appetite, nausea and vomiting, and damage to various organs that can result in loss of normal body functions.
The effectiveness of current cancer treatments with respect to any particular patient varies greatly, depending upon the cancer diagnosis and the tolerance of the individual patient to treatment. Therefore, a significant need exists for new agents that can be used alone or in combination with existing drugs and treatment approaches and that will produce greater efficacy and less toxicity than current therapeutic options.