What are the risk factors for Cancer?
A number of genetic and environmental factors increases the risk of developing cancer. Family history is one important factor. Some families have a significantly higher risk of developing certain cancers than other families. For example, a woman's risk of developing breast cancer increases up to 3 times if her mother or sister had breast cancer. Some breast cancers are linked to a specific gene mutation, more common in some ethnic groups and families.
   A number of environmental factors increase the risk of cancer. One of the most important is cigarette smoking. Smoking cigarettes substantially increases the risk of developing cancers of the lung, mouth, larynx, breast, cervix, colon, and bladder.
   The destruction of the body's natural rhythms accelerated the growth of cancerous tumors in laboratory animals.

Natural Therapies worth trying
These include yoga, hypnosis, meditation, biofeedback, imagery, and support groups.

Cancer statistics
Cancer statistics show death rates from cancer were lower by 2 percent per year from 2002 through 2004. There were declines in deaths from lung, prostate and colorectal cancers in men, as well as in breast and colon cancer among women. Drops in cancer rates may be due to effective tobacco control, screening, early detection, and a drop in the use of estrogen hormone replacement in women. The study was conducted by the National Cancer Institute, the CDC, the American Cancer Society and the North American Association of Central Cancer Registries.

Bladder Cancer
Cigarette smoking is confirmed as a risk factor for bladder cancer.

Brain Cancer
The number of brain tumor cases in the US and Europe has increased by up to 40% in the past 20 years. The incidence rate for brain tumors is increasing among people of all ages, but males between 20 and 40 years old are the most affected. The latest epidemiological studies indicate that white collar workers--intellectuals and professionals--are among the most affected. The reason is still unknown, though environmental causes such as cellular phones, computers and exposure to electromagnetic fields cannot be ruled out.
   Children fathered by men who have been exposed to polycyclic aromatic hydrocarbons (PAH) apparently have increased odds of developing brain tumors.  Experimental evidence suggests that parental exposure to PAH, which occurs primarily through tobacco smoke, occupational exposure, and air pollution, could increase the risk of cancer during childhood.

Breast Cancer
The incidence of female breast cancer dropped substantially from 2001 through 2004. This drop is possibly related to declining use of hormone replacement therapy.
   Breast cancer is the most common non-skin malignancy in women in the United States and is second only to lung cancer as a cause of cancer-related deaths. Women who are aged 50 to 69 years, and who are concerned about breast cancer, should be encouraged to have a mammogram every one to two and a half years along with a medical exam.  Eighty five percent of breast cancer cases occur after age 50. Most common type is infiltrating ductal carcinoma, but the more aggressive types are medullary and inflammatory. Women aged 40 to 50 should have regular mammograms if there is strong family history of breast cancer, particularly if the breast cancer was diagnosed before menopause.
   Breast self-exams have not been found to be definitively helpful. Breast self exam increases the number of false positive results. These may result in follow-up testing or invasive procedures such as breast biopsies, leading to anxiety, inconvenience, discomfort, and additional medical expenses. .
   There is a higher risk of breast cancer with early menarche and late menopause. The more a woman breast feeds, the more she is protected against breast cancer.
   There is also a higher risk with oral contraceptives and hormone replacement therapy, including several forms of estrogen, and probably androstenedione, dehydroepiandrosterone and testosterone. Women who already have breast cancer should not take additional hormone replacement, particularly estrogens.
   Risk of breast cancer decreases in women who are physically active. Women who work night shifts have a higher rate of breast cancer.
   Even moderate physical activity--for example brisk walking for at least 2 miles three times a week--over the course of a lifetime can reduce a young woman's risk of developing cancer by 33%, and the risk of breast cancer after menopause by 26%, according to results of a study of women living in the San Francisco Bay area.
   Having breast cancer tissue sampled with a needle seems to increase the odds that disease will also be found in an armpit lymph node called the sentinel node, new research suggests. The spread of breast cancer to the sentinel node adversely affects a woman's survival and influences the treatment received. As reported in the Archives of Surgery, Dr. Nora M. Hansen of the John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California hypothesized that the method used to obtain specimens from the breast tumor might influence the spread of cancer to the sentinel node. To investigate, the researchers studied 663 women with proven breast cancer. Of the cancers, about half were biopsied with a needle, while the remainder involved actual removal of the tumor. Women who had a needle biopsy were about 50 percent more likely to have cancer in the sentinel node than women who underwent tumor removal. The researchers suggest that the increased risk of sentinel node disease may be "due in part to the mechanical disruption of the tumor by the needle," and they call for further studies to confirm these findings. SOURCE: Archives of Surgery, June 2004.
   A high-fiber low-fat diet reduces blood levels of estrogen in women with breast cancer. This may help keep the disease in check, as breast cancers are sometimes driven by female hormones.

Breast cancer and body weight
Breast cancer patients who are overweight have more aggressive disease and are likely to die sooner.

Breast cancer and exercise
Women can reduce their breast cancer risk by being physically active. Very active women are significantly less likely to develop breast cancer than their sedentary peers.

Cervical Cancer
Screening should begin within 3 years after a woman begins having vaginal intercourse, but no later than 21 years of age. If traditional Pap test results are obtained, screening should be done every year. If liquid-based Pap tests are used, screening should be done every 2 years. Many American women who have had a complete hysterectomy are having Pap smear screenings even though they are not at risk of cervical cancer.
   For women who reach 30 years of age and have had three consecutive tests with normal results, screening can be done once every 2 to 3 years. However, for women with risk factors such as HIV infection or a compromised immune system, physicians may suggest screening be done more often.
   Women 70 years of age and older who have had three or more normal Pap test results and no abnormal results in the last 10 years may choose to stop cervical cancer screening.
   Women who take the birth control pill could be increasing their risk of cervical cancer. The longer women use the pill the greater their chances of developing the disease.
   Women infected with human papillomavirus (HPV) may reduce the odds that the virus will persist by increasing the amount of certain carotenoids-- plant compounds with antioxidant properties - in their diets. Specifically, the study found that increasing dietary intake of lutein/zeaxanthin, beta-cryptoxanthin, , and papaya appears to lower the risk of persistent HPV infection, a strong risk factor for cervical cancer.

Colon Cancer
Eating lots of preserved meats such as salami, bacon, cured ham and hot dogs could increase the risk of bowel cancer by 50 percent. Fiber found in vegetables, fruits, and whole grain cereals and legumes may reduce colon cancer risk. A daily calcium supplement protects against colon polyps, particularly the advanced type that go on to become cancer. Sigmoidoscopy is recommended every 5 years starting at age 50.
   Despite recent advances in screening and treatment for colon cancer, the number of people dying from the disease has remained steady since the late 1980s. Obesity is related to colon cancer risk.

Endometrial Cancer
Risk factors are unopposed estrogen therapy, late menopause, tamoxifen, nulliparity, infertility, polycystic ovary syndrome, diabetes, and obesity. Most endometrial cancers are diagnosed at an early stage when there is unexpected bleeding or spotting.
   Regular consumption of soy foods seems to reduce a woman's risk of getting cancer of the endometrium, the lining of the uterus, according to a study conducted in Shanghai. This benefit is most pronounced among overweight women. The estrogens women produce are known to play a key role in the development of endometrial cancer, the researchers note in this week's British Medical Journal. Soy foods contain isoflavones with both estrogen-like and anti-estrogen activities.

Esophageal Cancer
Carbonated drinks may raise the risk of esophageal cancer. A team at Tata Memorial Hospital in India found a strong correlation between the rise in per capita consumption of carbonated soft drinks in the past 50 years and a documented increase in rates of esophageal cancer in the United States. Team members studied U.S. Department of Agriculture data to find that per capita consumption of carbonated drinks rose by more than 450 percent, from 10 gallons on average in 1946 to 49 gallons in 2000. And over the past 25 years, the incidence of esophageal cancer has risen by more than 570 percent in white American men. Esophageal cancer affected 13,900 U.S. men and women in 2003, of whom more than 10,000 were men, and killed almost all of them, according to the American Cancer Society. The number of esophageal cancer cases clearly followed the rise in intake of carbonated soft drinks, the researchers found.

Gastric cancer
Treatment with the combination of cisplatin, epirubicin, L-leucovorin, and 5-fluorouracil, referred to as the PELF regimen, has little or no effect on overall or disease-free survival in patients with completely resected gastric cancer. J Natl Cancer Inst 2008;100:388-398.

Oral cancer
Betel nut chewing is a risk factor for oral cancer.

Ovarian Cancer
Increased risk with postmenopausal estrogen use. Decreased risk with aspirin use. Women who eat plenty of carrots, tomatoes and other foods high in carotene and lycopene may reduce their risk.

Pancreatic Cancer
Physical activity decreases risk, obesity increases risk. A diet high in vegetables reduces the risk of pancreatic cancer. Smokers who consume diets rich in saturated fat may be at increased risk of pancreatic cancer.

Prostate Cancer
Exercise, maintaining normal body weight, eating fish, legumes, flaxseed, yellow-orange vegetables, and cruciferous vegetables lowers prostate cancer risk. There is debate about the benefits of a PSA test but most doctors will order one in men over the age of 50. New research indicates PSA testing every 4 years is as effective as annual testing. After age 50, tall men have a moderately higher risk of developing prostate cancer than their shorter peers. The rate of increase in prostate-specific antigen level may be more important for predicting cancer than the actual PSA number
   Ejaculation frequency is not related to increased risk for prostate cancer.
   Use of supplements containing selenium may reduce the risk of advanced prostate cancer. The fact that no effect was seen against early prostate cancer suggests that selenium works by slowing cancer progression rather than by preventing it all together. A recent study links the consumption of the essential mineral selenium with a lower risk of prostate cancer. There are now seven population studies in the past six years that examined the possible connection between selenium and prostate cancer. All but one of them have found selenium protective. Yet, since scientists are still uncertain how prostate cancer starts or can be prevented, it is too early to say that selenium definitely protects the prostate.
   Men over 50 who have higher levels of testosterone have a higher risk of prostate cancer. The findings may mean that men should be cautious about testosterone replacement therapy, being tested in older men who see a decline in general health and vigor.
   Side effects of prostate cancer treatment, such as impotence and urinary incontinence, are far more common than most doctors admit.

Anemia drugs used for cancer treatment
Anemia is a common complication of cancer treatment. Treating cancer patients with anemia drugs increases their risk of blood clots and death. Erythropoiesis-stimulating agents. or ESAs, raise the risk of death in patients who take them compared with those who do not, a finding that can not be explained by the higher blood clot risk alone.

Cancer studies
The Unending Debate: Do Vitamin Pills Prevent Cancer?
For several decades the scientific community has debated whether vitamin and mineral supplements prevent or reduce the risk of cancer. Over the years numerous studies have given contradictory results leaving the medical community uncertain of what to recommend to the public. In this latest study, scientists, from the Scientific and Technical Institute for Nutrition and Diet in Paris, France gave a vitamin/mineral supplement to thousands of men and women. A total of 13,000 men and women aged 35 to 60 took part in the study. Half were given a daily supplement containing 6mg of beta-carotene, 120mg of vitamin C, 90mg of vitamin E, 100 micrograms of selenium, and 20 milligrams of zinc. A dummy capsule was given to the other participants. At the end of seven years, the researchers found that taking the supplement had no effect on heart disease, and did not influence cancer rates in women. But they found a 31% reduction in the risk of all cancers in men taking the antioxidants. And, overall, the death rate was 37% lower among men who took the supplement. The researchers, said: "Our findings support recommendations for following a healthy diet, particularly one rich in fruit and vegetables which are major dietary sources of antioxidant vitamins and minerals, for all ages in life and for both sexes." They added that women may not have received the same benefits because their diet were better than those of men and they perhaps were already ingesting many healthy antioxidants through their diet.
     Comments: The debate seems to continue regarding the role of vitamin/mineral supplements and the prevention of cancer. It appears that those with a very health diet rich in fresh fruits and vegetables are not likely to reap much benefit from supplements, but those with a marginal diet would.