Cancer, by the numbers

HEALTH

By Tammy Worth

July 6, 2009

Increased screening and improved treatments are the predominant reasons for the reductions in deaths in many types of cancer.

Screening for prostate cancer, for example, has led to a dramatic increase in the discovery of early-stage prostate cancer, says Peter Scardino, chairman of the department of surgery at the Memorial Sloan-Kettering Cancer Center. Treatment options include radiation, surgery and hormone therapy.

But Scardino says too much screening can lead to over-treatment. He urges patients to avoid unnecessary therapies because the measures can have side effects such as bowel, sexual and urinary dysfunction.

Further, many cases of prostate cancer are slow-growing, and even many men with the disease are likely to die of other causes first.

The breast cancer picture is more complex.

First, the report notes there has been a slight reduction in the use of mammograms, leading to fewer diagnoses. Second, a significant number of women stopped taking menopausal hormone therapy after it was found to have a link to breast cancer. And third, the drugs tamoxifen and raloxifene have been effective at preventing cancer in some high-risk women.

Here are statistics on the four leading types of cancer:

Lung cancer

* An estimated 219,440 new cases of lung and bronchus cancer are expected this year, with 159,390 deaths.

* In men, the number of cancer cases began decreasing by about 1% annually after 1990 and 2% after 1994.

* In women, the disease is just beginning to plateau. These numbers reflect the change in smoking patterns between the sexes: Women began smoking later and stopped smoking later than men.

Colorectal cancer

* An estimated 146,970 cases of colon and rectal cancers are expected this year, with 49,920 deaths. Together, these are the third most common cancer.

* Mortality rates have decreased by 4.3% since 2002, and incidence rates have dropped from 66.3 cases per 100,000 people in 1985 to 46.4 cases in 2005, largely due to early detection and removal of precancerous polyps.

* Ninety-one percent of cases will be diagnosed in people 50 and older, with the risk increasing dramatically with age.

* The risk of developing colorectal cancer can be increased by obesity, physical inactivity, smoking, too much red meat and alcohol consumption, and too little fruit and vegetable intake.

Prostate cancer

* An estimated 192,280 cases of prostate cancer are expected this year, with 27,360 deaths.

* The number of men being diagnosed with prostate cancer has been decreasing by about 4.4% annually since 2001, largely due to changes in screening.

* Because of early detection, the five-year survival rate for a majority of these diagnoses will be 100%. But because of intense screening, many men will undergo biopsies -- facing the risk of serious side effects -- only to find they don't have cancer.

Breast cancer

* An estimated 192,370 new breast cancer diagnoses are expected this year in women and 1,910 new cases in men, with an estimated 40,610 deaths.

* The death rates for women with breast cancer have been on the decline since 1990, and the incidence rates have been decreasing since 1999.

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