Cancer, a haunting specter
When I was in my 20s, conversations with friends often focused on relationships and career; in my 30s, more often than not we talked about children. Now I’m in my 40s, and the topic of cancer seems to be creeping into our discussions with surprising frequency.
“When I was younger, I don’t remember so many people being diagnosed with cancer,” says Lisa Gross, whom I’ve known since my children were young. “Now it seems that every other day, you hear about someone getting it.”
Some of my friends worry that cancer is more common than it used to be -- that we are experiencing a cancer epidemic of sorts. It’s easy to understand why they feel this way, with cases of cancer cropping up all around them and affecting people they know. But the statistics suggest otherwise.
The Annual Report to the Nation on the Status of Cancer, released in October, found that cancer incidence rates (or the rates at which new cancers are diagnosed based on the size of the population) have stabilized and, for many of the most common forms of cancer, are actually dropping. “It’s a pretty favorable picture right now,” says David Espey, a cancer epidemiologist with the Centers for Disease Control and Prevention.
Among men, incidence rates for lung cancer (the leading cause of cancer death in men) decreased by 1.8% a year from 2001 to 2004, and rates for colorectal cancer fell by more than 2% annually. Perhaps most impressive were the changes in the incidence of breast cancer, the second-leading cause of cancer death in women, behind lung cancer. Those rates for women dropped by 3.5% a year during this period.
Cancer experts can’t pinpoint exactly what is responsible for these encouraging trends, but they have a pretty good idea of what may be influencing some of them. The decrease in lung cancer cases is clearly related to the fact that fewer people are smoking than in the past. Less smoking means less risk.
The recent decline in breast cancer cases may also be tied to a widespread reduction in risk. “The biggest driver is probably the decreased use of hormone replacement therapy in post-menopausal women,” says Espey. In 2002, the Women’s Health Initiative found that the long-term use of replacement therapy increased a woman’s risk of breast cancer. Since the study’s release, the use of the therapy has fallen substantially.
For other types of cancers, screening appears to have had an effect. Though tests for cancer are generally used to detect malignancies in their earliest stages, some can actually help avert their development. Sigmoidoscopy and colonoscopy, for example, detect polyps in the colon that can go on to become cancerous. Removing these cancer precursors during routine screenings greatly diminishes the possibility of developing cancer.
Pap smears protect against cervical cancer in a similar way. These screening tests identify pre-malignant abnormalities which, when detected and treated early, nearly eliminate the risk of cancer.
In spite of the largely encouraging cancer trends, the news isn’t all good. Cancers of the thyroid, bladder and kidney as well as certain forms of leukemia and lymphoma are on the rise in women; among men, cancers of the liver, kidney and esophagus are increasing. In some cases, little is known about the cause for these upswings; in others, it is less mysterious. With liver cancer, alcohol abuse and hepatitis C infection play a role; improved diagnostic tests are probably partially responsible for the uptick in thyroid cancer, because they detect cases that in the past would not have been found.
Though overall cancer rates are falling in the U.S., the absolute number of cases of cancer is expected to rise. “We are an aging and growing population,” says Brenda Edwards, associate director of the National Cancer Institute’s cancer surveillance program. “There are simply more people at greater risk for developing disease.”
I understand people’s concerns about cancer. Several of my friends have been diagnosed with cancer in the last year or two, and sometimes I can’t help but wonder if I’ll be next. (A recent bout of hip pain had me convinced I had a bony tumor until my husband pointed out that the pain went away with rest -- an unlikely scenario if I had cancer.)
To curb my own worry, I force myself to step back and look at the issue more critically. I focus on the trends and the probabilities. I also remind myself that I am not as powerless against cancer as I may sometimes feel. I can take steps to dramatically reduce my risk of developing the disease, such as maintaining a healthy weight, eating right and getting screening tests. There is nothing, however, that I can do to slow the march of time. The fact remains: More than three-quarters of all cancers are diagnosed in people 55 and older. Though I haven’t reached my 50s yet, I’m getting close. And, like it or not, cancer is likely to come up more frequently in conversation.
“And I thought wrinkles were going to be the worst part about getting old,” says Gross.
Dr. Valerie Ulene is a board-certified specialist in preventive medicine practicing in Los Angeles. She can be reached at firstname.lastname@example.org. The M.D. appears monthly.