The two clear messages of the graphic are that women, black and white, have a higher survival rate than men and that blacks, of both sexes, have a lower survival rate than whites. This graphic shows only selected cancer sites. All data are presented in Part II in tabular format.
The highest survival rates are shown for prostate cancer. The malignancy now has a new early-warning screen, the PSA blood test. The disease spreads slowly. Surgery can be used to remove the malignancy in most cases — i.e., when the cancer has not metasta- sized. Ovarian cancer is difficult to detect early, has often spread by the time it is discovered. Symptoms are vague. Symptoms of cervical and uterine cancer speak louder, as it were. And breast cancer detection has been greatly aided by mammography, which is strongly promoted by the health authorities. The only cancer where males survive fractionally longer than females is with cancer of the colon: men lead by 1.1% survival.
It is noteworthy, in contemplating this graphic, that in no case does the survival rate reach 100%. This means that our methods of prevention, surveillance, and treatment are not working very well. Cancer is a killer. A brief look at the important methods of treatment show us why.
Once cancer has begun, it is analogous to our current war on terrorists. We claim we don't know why terrorists hate us. Similarly, we don't understand why cancer cells multiply. We are left with the task of destruction. Our ability to see is limited. Areas we have pacified can revive. In the process of destroying the enemy, we harm the innocent. Thus radiation therapy damages healthy cells — and can sometimes, after years of delay, cause leukemia. Chemotherapy designed to attack and to destroy rapidly growing cells also destroys healthy cells, damages tissue. Both treatments have severe side-effects and weaken the body.
The treatment of cancer is, in this preferred order: surgery, radiation, and chemotherapy. Each technique is less specific, going from left to right, and has greater side effects. Sometimes the last two are used in preparation for or during surgery as well.
Surgery is indicated when the disease is localized and hasn't spread. Radiation therapy, similarly, is applied to the cancer site itself. Chemical agents are useful when the disease has spread — because the chemicals can reach cells beyond localized points.
Leukemia and lymphatic cancers are treated by radiation therapy and chemotherapy exclusively. Only about of fifth of pancreatic cancers can be treated surgically. In lymphoma, bone marrow transfers are a treatment, in leukemia blood transfusions. Hormone therapy is associated with uterine and breast cancer. In cervical cancer, cryotherapy (freezing cancer cells), electrocoagulation (burning the cells), and laser ablation (cutting them with concentrated light) are also used. New radiological techniques are in testing now. These techniques are designed to be more accurate in reaching the target, make use of sophisticated computer targeting of tumors, and operate so that surrounding tissues do not suffer "collateral damage."
The object in all of these cases — except the replacement strategies of bone marrow transfer and blood transfusions — is destruction. Even very sophisticated new techniques like antiangiogenesis therapy — which starves cancer cells of blood — are meant to destroy. A cure for cancer would be to prevent the defective cells from forming in the first place.
Not surprisingly — in the absence of a cure — much emphasis is on managing risk factors — especially for those major cancers known to be caused by or are linked to behaviors like smoking and obesity. We conclude our look at cancer treatments by looking at prevention in the next panel. Much more information on prevention is presented in Chapter 3.
Source: National Institutes of Health, National Cancer Institute, from Health, United States, 2001, Table 56. Background data from American Cancer Society, accessible at http://www.cancer.org.
User Comments Add a comment…