Archive for the ‘Cancer’ Category
INCIDENCE OF CANCESex does not affect the incidence of the disease. However, proportion of cancer in males and females is roughly 10:12. It also affects the site of growth. In men, cancer is usually found in the intestines, the prostate and the lungs. In women, it occurs mostly in the breast tissues, uterus, gall-bladder and thyroid.Cancer occurs at all ages, from infancy to old age. There is a close relationship between cancer and aging. In the United States, over one-half of all cancers occur in 11 per cent of the population over the age of 65. At the age of 25, the probability of developing cancer within five years is one in 700, while at the age of 65, it is one in 14. The peak incidence and mortality of cancer is in the 60-70 age range.Although deaths attributable to cancer decrease from 30 per cent at age 50 to 10 per cent or less at age 85, this is largely due to rapid increase in death due to other causes with advancing age, and not due to non-prevalence of cancer. Despite the marked increase in cardiovascular related deaths with age, cancer remains the second leading cause of death in those over 65.Cancer is not contagious or infectious. This is clearly evident from the fact that a large number of members of the medical profession and technicians come in close contact and handle cancer tissues in the course of treating patients, but they do not get cancer any more than other sections of the people. No infective agent has so far been detected from cancer tissues.*5/355/5*
You remember the lymph node system that I described in Chapter 2? How can we check whether or not the cancer has spread through this system?
Normal lymph channels are like cotton threads. Normal lymph nodes (glands) are soft, smaller than a pea and cannot be felt through the skin. If cancer gets into the lymphatic system it usually grows in the lymph nodes, making them bigger and harder. This is usually painless.
Much less often, lymph spread takes a different form—the cancer can actually grow in the lymph channels. If the affected channels are in the skin, the appearance is usually that of a raised, red ‘rash’. One of the most troublesome sites for this type of spread is in the lungs. The solid cores of cancer cells running through the lymphatic vessels make the lungs very stiff. This causes cough and shortness of breath. Unfortunately this problem can be hard to diagnose, because it is often difficult to see on an X-ray in the early stages.
If the cancer fills the nodes or blocks the lymph channels, it prevents that part of the lymph system from carrying out its usual job. One of these is to drain excess fluid from the tissues. So, for example, if the affected nodes are in the armpit, the arm may swell up.