Good news on a major killer: US cancer deaths continued to fall between 1999 and 2016.
So finds the latest Annual Report to the Nation on the Status of Cancer, from a consortium of leading cancer organisations.
More progress needed
The report also found that the rate of new cancer cases fell among men from 2008 to 2015, after increasing from 1999 to 2008, and was stable in women from 1999 to 2015.
Still, much more progress is needed.
"Major declines overall in cancer mortality point in the right direction, yet significant differences remain in cancer cases and deaths based on gender, ethnicity and race," said Dr Robert Redfield, director of the US Centers for Disease Control and Prevention.
Overall, cancer death rates decreased 1.8% per year in men and 1.4% per year in women, continuing an ongoing trend.
From 2011 to 2015, cancer incidence rates – the rate of new cases – were stable in women and decreased 2% per year in men.
Why men are charting a bit more improvement in avoiding cancer compared to women isn't clear, Redfield said.
"A better understanding of these discrepancies improves cancer diagnosis and recovery for all patients and is vital to our public health mission," he said in a news release from the US National Cancer Institute (NCI).
Obesity a risk factor
Among individual tumour types, progress appears to be continuing against lung cancer, largely due to declines in smoking; and against melanoma skin cancer, due to new and better treatments.
On the other hand, cancers where obesity is a risk factor – early-onset colon cancer, breast cancer in older women, and uterine cancers – are on the rise.
A special section of the report tracked cancer rates for younger Americans – those aged 20 to 49. It found that, in this age group, cancer incidence and death rates were higher for women than men.
From 2011 to 2015, the average annual incidence rate for all invasive cancers in this age group was 203 per 100 000 among women and 115 per 100 000 among men, the report found.
Lead author Elizabeth Ward, a consultant at the North American Association of Central Cancer Registries (NAACCR), said, "The greater cancer burden among women than men ages 20 to 49 was a striking finding of this study."
Among this younger cohort, cancer incidence rates fell an average of 0.7% a year among men but rose an average of 1.3% per year among women, the report found. And from 2012 to 2016, the average annual cancer death rate was 27 per 100 000 among women and nearly 23 per 100 000 among men in this age group.
Still, some improvements were seen: From 2012 to 2016, cancer death rates fell overall for young Americans. The death rate fell 2.3% per year among men and 1.7% per year among women, the report found.
High burden of breast cancer
Among Americans aged 20 to 49, the most common cancers and their incidence rates among women were breast cancer (73 per 100 000), thyroid cancer (28 per 100 000), and melanoma (14 per 100 000).
The most common cancers among men in this age group were colon and rectal cancer (13 per 100 000), testis (nearly 11 per 100 000), and melanoma (10 per 100 000).
Younger women's heightened vulnerability to cancer compared to their male peers appears concentrated in one cancer type, Ward noted.
"The high burden of breast cancer relative to other cancers in this age group reinforces the importance of research on prevention, early detection, and treatment of breast cancer in younger women," she said.
And Dr Douglas Lowy, acting director of the NCI, said that "it is important to recognise that cancer mortality rates are declining in the 20- to 49-year-old age group, and that the rates of decline among women in this age group are faster than those in older women."
Betsy Kohler, executive director of NAACCR, added that, overall, "We are encouraged by the fact that this year's report continues to show declining cancer mortality for men, women and children, as well as other indicators of progress. There are also several findings that highlight the importance of continued research and cancer prevention efforts."
The report was published in the Journal of the National Cancer Institute.
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