Why do healthy people get cancer?

Have you ever noticed that people who make healthy diet, exercise, and living choices still seem to get cancer more frequently than you might expect? I cannot count the number of times that I have heard that remark from family and friends.

Recent studies by a mathematician and cancer geneticist team at Johns Hopkins University help to explain why healthy people still develop cancer.

This new research suggests that a lot of generally-held beliefs about what causes cancer may be misplaced.

According to the Johns Hopkins research, only 29% of cancers are caused by environmental factors like smoking or too much sun exposure, and just 5% of tumors are caused by genetic mutations that we inherit.

That leaves an astounding 66% of cancer cases that are caused by random copying errors that occur during the natural process of cellular division. When it comes to some types of cancer, like bone and brain cancer, 95% of cancer-causing mutations are caused by random copying errors. The more often cells divide the higher the risk of a copying error.

There are two take-home messages from the Johns Hopkins studies.

First, most of the time, cancer is caused by bad-luck copying errors and there is nothing that you can do to prevent it.

Second, whether you live an athletic and healthy lifestyle or not, cancer screening is important.

American Cancer Society Guidelines

The American Cancer Society has developed evidence-based general cancer screening guidelines for adults, which can allow diagnosis of cancer before there are any noticeable symptoms. You should talk to your doctor to see if you need screening more often, based on family history, genetic tendencies, or other test results. The screening guidelines include the following:

Breast cancer. Women ages 40-44 should consider annual mammograms. Women ages 45-54 should get mammograms every year, and women 55 and older need them at least every two years.

Colon and rectal cancer and polyps. Starting at age 50, men and women should follow one of these options for polyps and cancer: (1) flexible sigmoidoscopy every five years; (2) colonoscopy every 10 years; (3) double-contrast barium enema every five years; or (4) CT colonography (virtual colonoscopy) every five years. In addition, there are some stool testing options that mostly find cancer; (1) yearly guaiac-based fecal occult blood test (gFOBT); (2) yearly fecal immunochemical test; and (3) stool DNA (sDNA) test every three years.

Cervical cancer. Women between 21-29 should have a Pap test done every three years. Women ages 30-65 should have a Pap test plus an HPV test every five years, or a Pap test only every three years. Women over 65 who had regular testing for the previous 10 years do not need further testing.  Women who had a total hysterectomy unrelated to cervical cancer do not need testing.

Lung cancer. There are no screening recommendations for the general public. For some smokers, there is a recommended annual low-dose CT scan (LDCT), if they meet these criteria: 55-75 years of age, in good health, who have a history of smoking at least 30 packs per year and are either still smoking, or quit smoking in the last 15 years.

Prostate cancer. Research has not yet proven that the potential benefits of testing outweigh the harms of testing and treatment. Thus, there are no general screening recommendations, other than men 50 or older taking to their doctors about the pros and cons of having a PSA blood test with or without a rectal exam.

Medical negligence and missed diagnosis

As a Houston medical malpractice lawyer, I have handled a number of cases where clients were following these screening recommendations, but the doctors or labs made a mistake, resulting in a missed or delayed diagnosis of cancer. In other cases, doctors or pharmacists have made medication errors that led to ineffective treatment once cancer was diagnosed.

When it comes to cancer, experts consistently tell us that early diagnosis and proper treatment are the two main factors that influence outcome and survival.

If you or someone you care for had been seriously injured because of a misdiagnosis of cancer, or the wrong treatment for cancer or a medication error, call 281-580-8800 for a free consultation with the experienced Texas medical malpractice attorneys at Painter Law Firm.

Robert Painter
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Robert Painter

Robert Painter is an award-winning medical malpractice attorney at Painter Law Firm Medical Malpractice Attorneys in Houston, Texas. He is a former hospital administrator who represents patients and family members in medical negligence and wrongful death lawsuits all over Texas. Contact him for a free consultation and strategy session by calling 281-580-8800 or emailing him right now.