The introduction of antibiotics rapidly extends life expectancy
Until the end of World War II in 1945, the average life expectancy of humankind remained largely unchanged at around 50 years.
Since then, life expectancy improved rapidly owing to the discovery and widespread use of antibiotics (such as penicillin) and anti-tuberculosis agents, and today, a life span is considered to be 80 years in developed countries. A gain of 30 years in average life expectancy within a time frame of 50 years is a revolutionary achievement in the history of humankind. However, due to aging populations, cancer has become a major cause of mortality in developed countries, and its treatment has become a serious issue.
In the United States, cancer treatment centers were established one after another during the 1940s to 1950s. The National Cancer Institute on the east coast of the United States and the Memorial Sloan-Kettering Cancer Center in New York are famous institutes for cancer treatment and research.
Back in those days, the principal treatment for cancer was surgical treatment, and radiation therapy was used additionally as required. There was much hope that anti-cancer agents would be just as potent in cancer as were antibiotics in infectious diseases. Treatment methods superior to both the surgical knife and radiation were sought. Of course, that was a time when techniques in surgical anesthesia and radiation equipment were far more inferior compared to what we have today.
Development of anti-cancer agents begins in the 1950s, led by the National Cancer Institute
The discovery that a poison gas called mustard gas was effective in malignant lymphomas originated from hints gained from clinical observations of exposed soldiers in World War I. That discovery was made in the 1920s. Although several agents were effective, at least for a temporary period, such agents were primarily targeted for leukemia or malignant lymphomas. It was already known at the time that these agents would have little effect in tumor-forming cancers that occur in adults, such as stomach cancer and colorectal cancer.
These agents also caused strong adverse effects. The research and development for new substances began in the 1950s, and was led by the US National Cancer Institute. Tens of thousands of different chemical substances were searched through, and narrowed down to those with development potential. Taxol, currently used as an anti-cancer agent, is one of the key products resulting from the anti-cancer drug development initiative in the US. Enormous federal funds and human resources were invested for its development.
Unfortunately, however, there are no anti-cancer drugs at present that are as revolutionary and superior in their action as antibiotics. People are waiting for extremely effective anti-cancer drugs that have no adverse effects. It may be necessary here to explain how anti-cancer drugs work, as well as outline some of the characteristics of cancer.
Anti-cancer drugs destroy DNA or nuclear substances of rapidly-growing cells
Cancer in adults is very different from cancer in children. In children, leukemia, malignant lymphomas, cancer of the retina, and brain cancer are common cancers. In adults, cancer typically forms tumors in organs such as the stomach, colon, lung, mammary gland, prostate gland, and uterus (these are also known as “solid cancers” as it occurs in solid organs).
Adult cancers grow slowly. Anti-cancer agents attempt to destroy DNA and nuclear substances of rapidly growing cells. If anti-cancer agents enter a person’s body within which cancer cells are growing slowly, healthy cells will be destroyed first, resulting in noticeable adverse effects.
Most cancers in adults grow slowly, so anti-cancer agents cause greater damage to healthy cells than to cancer cells. New drugs are currently being developed to overcome this problem, including drugs with molecular targets that selectively destroy substances on the cell surface associated with the growth of various cancers, and vascular targeting agents that disrupt the blood flow to tumor cells and starve them of nutrients.
The development of the “dream anti-cancer drug” is still a long way to go
Scientists still have not found an apparent “cancer mark” that distinguishes between cancer cells and healthy cells, which would enable cancer cells to be attacked like a patriot-missile attack. We often hear about the serious adverse effects of new anti-cancer drugs on the news. Unfortunately, it is still a long way to go before the development of the “dream anti-cancer drug”.
Given the current situation, the ideal medical care would be one in which the patient, the patient’s family and the medical team are united as one in a relationship of trust (and sharing the same viewpoint), with the cancer patient at the center of the team. Ideally, explanations about the cancer and the limitations of anti-cancer agents and their adverse effects will be accurately explained to the patient, so that the patient can understand his or her own circumstances. Furthermore, it is necessary for both the doctor and patient to actively participate in discussions on the difference in prognosis resulting from the use or non-use of chemotherapy, and in discussions on other possible treatments.
When considering treatment options, it is important to consider complementary and alternative medicines, and not only limit one’s options to modern medicine. Why? It is because modern medicine is not perfect. And, if medical care aims to provide a comprehensive treatment for each person as a whole, we would need to return to the origins of Hippocrates. I plan to return to this point again in a later article.