A cancer diagnosis is no longer the death sentence it once was. Many researchers are predicting that in this decade or the next, cancer will be considered a chronic disease people can live with, and managed much like diabetes is today.
Here's why: thanks to advances in biology and genetics, today's researchers are armed with new knowledge of the molecular abnormalities in cancer cells. Strategies are being developed to interrupt cancer at every stage, preventing it from developing in the first place, eliminating it when discovered early, and intervening and modulating its devastating effects when it's taken hold. That's brought a new generation of targeted drugs, some already proving very effective.
Where traditional chemotherapies bluntly attack rapidly-dividing cells, regardless of origin, function, or health, drugs are now being designed to fix specific molecular problems. Dr. Karen Antman explains. "Drugs in the past were targeted but were not quite as clean, because scientifically we didn't have as many targets as we do today."
Dr. Antman directs research at the National Cancer Institute's headquarters in Bethesda, Maryland. "In the last decade the numbers of drugs that are under development are substantially more. We understand them better, and the activity of the drugs is much better, so that we do have more active drugs with fewer side affects."
In early clinical trials, some anti-cancer vaccines are surpassing expectations; providing new, limited proof that vaccines can be helpful in the war against some cancers. Some vaccine studies that have eliminated cancer in laboratory animals by attacking proteins associated with cancer are at last being tested on humans. Dr. Antman says, "Most people are pretty familiar with vaccines for infectious diseases, and there are infectious disease related cancers. The best one, the poster child, is hepatitis B, which causes liver cancer, which is one of the major cancers in developing countries."
Worldwide tobacco use is the number one cancer killer, and despite educational efforts, smoking is becoming more common in the developing world. Dr. Antman talks about the causes of cancer. "The other causes of cancer haven't been totally worked out, but it certainly looks like habits. Infectious disease-associated cancers are much higher in developing countries than they are in developed countries. One specifically is cervical cancer. It is the major cause of cancer death in many developing countries, and that could be alleviated with better screening.
We have pap smears, pap tests, and therefore cervical cancer is not a major problem in developed countries. "If health care communities around the world had a simple means of preventing cervical cancer, hundreds of thousands of lives could be saved every year.
The Cancer Institute and its partners are pursuing vaccine trials to do just that. Finally the mapping of the human genome, a much-heralded international research project, is directly benefiting cancer study.
Dr. Antman explains. "Well, the human genome project basically gave us the index. Now there's a proposal for a cancer genome project where we could actually -- now that we're identifying the genes associated with various cancers -- we could actually do the sequencing of the genes that are associated with breast cancer, and the sequencing of the genes associated with lung cancer. And therefore in a period that's fairly short, perhaps a decade, you would have all the genes associated with cancers.
Therefore, you would be much more precise in determining which kind of tumor had developed in a patient, and which drug would be most appropriate for that patient, so it's personal medicine. We can't do that yet."
The institute has officially launched the cancer genome anatomy project, and scientific knowledge of the genetic changes in cancerous cells and tumor growth is rapidly expanding.
Researchers around the world, sharing new technologies, tools, and data bases are identifying and sequencing the genetic abnormalities in cancer patients and tracking treatment protocols, and that is ushering in a promising new era of molecular medicine and cancer treatment.
However, the optimism brought about by discovery of the genomic basis of cancer is lessened by the fact that even as cancer mortality rates begin leveling off in some western nations, cancer mortality is climbing among less affluent populations.