Cancer - Causes- symptoms- treatment -Tips to Prevent it

 Chemicals can cause cancer, and workers handling them should learn the safety rules as a means of primary prevention. Historically, it is interesting that one of the first chemically induced cancers to be noticed by doctors was in chimney sweeps whose contact with the tarry material in the chimneys led to cancers of the scrotum. 

Chromate chemicals today can cause lung cancer; aniline dyes can cause bladder cancer; asbestos can lead to cancers of the outer lining of the lungs or the intestinal cavity. Some 500 chemicals have been found to cause cancers in experimental animals. One of these, which were widely used as an artificial sweetener, cyclamate, was restricted after animal experiments produced cancers and led to fear that humans using it in large quantities over long periods might develop cancer. 

An additional reason for prevention of chronic liverdisease (page 611) is the tendency of this disease to allow cancer to be superimposed. Patients with ulcerative colitis need careful scrutiny because of their higher risk of developing cancer of the diseased colon. Secondary Prevention Once cancer is found, much can be done to prevent it from becoming a fatal illness. As we have indicated, cancer can be a curable disease. When the doctor discovers a lump in a breast or sees a suspicious sore on a lip, he must make a definitive diagnosis.

Usually this is possible only through removal of part or all of the suspicious area-biopsy- so a pathologist can examine it microscopically as well as grossly. If the diagnosis is cancer, then the physician considers the outlook for the patient in terms of localization versus metastasis or spread. If there has been spreading, the outlook is much less hopeful than if the cancer is still confined to the area of origin. For example, a breastcancer which has not spread to lymph nodes in the arm- pit offers a 70 percent or better chance for cure. 

If there has been a single metastasis, the chance for cure may drop to 50 percent. If there have been several metastases, the likelihood of living five years may drop to about 25 percent. Similarly, for example, a kidney cancer that has spread to a bone has a much more ominous outlook than one that is still confined to the kidney.

With metastasis, treatment usually depends upon radiation and chemicals, often less likely to provide permanent cure than when a surgeon can remove an entire intact growth at its primary site. Thus, early detection is the key to effective secondary prevention in cancer. Cancer in early stages rarely makes its presence known by such general symptoms as fever or loss of weight. It does, however, often provide local signals such as a painless lump in the breast or bleeding in stomach or rectum. 

Cardinal signs of cancer are lumps or sores that do not heal; bleeding from any part of the body when there is no obvious explanation for the bleeding; chronic hoarseness; chronic cough; unexplained stomach or intestinal symptoms such as constipation, diarrhea, nausea, vomiting, "indigestion"; unexplained pain; jaundice; impaired vision; convulsions; possibly headache.