PRESENT AND FUTURE RESEARCH
Most developed countries have programs of cancer research. In the United States the National Cancer Institute of the federal government and such private organizations as the American Cancer Society, the Damon Runyon-Walter Winchell Cancer Fund, and the Leukemia Society of America have focused on the support of cancer research and education. Researchers at the World Health Organization and such programs as the International Agency for Research on Cancer cooperate worldwide on cancer studies and public education on cancer.
Knowledge of the causes and control of cancer has increased dramatically in recent years. The role of infectious agents has significantly expanded the understanding of the causes of liver and stomach cancers. The virus causing hepatitis B has been known to cause a number of cases of liver cancer in the world, but recent evidence has shown that the virus causing hepatitis C also causes a large number of cases of liver cancer. Researchers are working on a vaccine for hepatitis C. A person infected with the bacterium Helicobacter pylori, an important inciting factor in gastric ulcers, also has an increased risk of gastric cancer with this infection. Appropriate antimicrobial therapy can eliminate the infection and the cancer risk.
Therapy in the future may be directed toward the chemical induction of differentiation of cancer cells into stable, nondividing cell populations. Evidence that some malignant cells can develop into perfectly normal cells when placed in the early embryo suggests that the neoplastic transformation is not always irreversible. Also, the potential for combination chemotherapy in human cancer has not been completely exhausted. Trials of new drug combinations will continue as long as this method offers the best hope for the cure of the greatest number of metastatic neoplasms.