Article posted Wednesday, February 11, 2015 4:26pm

There are hundreds of kinds of cancers, but all occur because something has gone wrong with a person’s genes and cells start dividing in an uncontrolled manner. This may take place because of damage to a gene, an alteration in a gene’s function, or the merging of two chromosomes that gives rise to an unwanted gene. Usually treated with radiation and chemotherapy, the latest thrust is the creation of specially targeted drugs. For example, in the case of chronic myeloid leukemia, a drug called Gleevac blocks a protein produced by cancer cells that is required for them to divide. Before availability of the drug, mortality rate was about 60 percent. After the drug began to be used, 90 percent of patients were alive five years after treatment. In certain kinds of lung cancer there is a specific gene that tells cells to divide in an uncontrolled manner. A drug called Xalcori blocks the expression of this gene – and many lung cancer victims survive. DNA sequencing of cancer cells is being used to track mutations so physicians know how to target treatments. Drugs are also being developed that ramp up the activity of the immune system so it can more fully participate in ridding the body of malignant cells. The bottom line is a hopeful one, for treatments that combine traditional therapies with targeted drugs and an enhanced immune response will undoubtedly mean longer lives for many cancer victims. Additional health care costs incurred by smokers in the U.S. every year total $96 billion. One wonders how much of this is paid for by non-smokers.

(Sources:  The Economist, Jan. 4, 2014; Scientific American, Nov. 2013; U.S. Communicable Disease Center).