Death rates from cancer in the United States continue to fall, but there has been an unexpected sharp rise in thyroid cancer cases among women in the past decade, a national report shows.
Overall cancer death rates dipped 1.6 percent annually for men from 1993 to 2003 and 0.8 percent annually for women from 1992 to 2003, according to the Annual Report to the Nation on the Status of Cancer, which was released yesterday .
“The good news is that cancer death rates continue to decline for men and women,” said Dr. Len Lichtenfeld, deputy chief medical officer for the American Cancer Society (ACS).
The report shows the biggest increase is in thyroid cancer incidence among women, which rose 9.1 percent annually from 2000 to 2003.
“Clearly, the increase in thyroid cancer among women has been very dramatic, and men have had an increase in this disease as well, which has not been insignificant,” Dr. Lichtenfeld said.
The report shows a 4.1 percent increase in thyroid cases among men.
Researchers are not sure about the cause for the increase in thyroid cancer.
Dr. Lichtenfeld suggests one theory: It was “not uncommon” a half-century ago for children with swollen tonsils to be treated with radiation.
“This increase [in thyroid cancer] is a phenomenon that was just recently recognized, and it could be related” to childhood radiation exposure from tonsil therapy, he said.
About 327,000 Americans are living with thyroid cancer, and more than 250,000 are women, according to data from the National Cancer Institute (NCI).
Women will account for nearly 22,600 of the more than 30,000 cases of thyroid cancer diagnosed this year, according to the report compiled by NCI and ACS in collaboration with the North American Association of Central Cancer Registries.
The report also found that the rate of breast cancer cases, which had been rising steadily since 1980, appears to have leveled off. Incidence in women declined 0.5 percent annually between 1995 and 2003, but analysts say it is still too early to call that a trend.
Among men, death rates are declining for cancer of the lungs, prostate, colon and rectum, pancreas, bladder, stomach, mouth, brain and central nervous system. They also are decreasing for leukemia, non-Hodgkin’s lymphoma and myeloma, a malignancy that starts in the bone marrow. Cancers that are either stable or rising in men are melanoma, and tumors of the esophagus, liver and kidneys.
For women, death rates are decreasing for cancer of the breast, colon, rectum, brain and nervous system, stomach, kidney, cervix and bladder, as well as non-Hodgkin’s lymphoma and leukemia. But death rates were stable or rising with cancers of the lungs, pancreas, ovaries, uterus and liver.