Researchers have reported that a rare and aggressive uterine cancer seems to be on the rise in the United Sates, and the trend seems particularly so among black women.

A group of researchers looked at racial and ethnic differences in hysterectomy-corrected uterine cancer deaths and found that deaths from the aggressive form of cancer have risen 2.7% over the last eight years. Deaths for the less aggressive form of uterine cancer have been stable, and black women had over twice the rates of death from uterine cancer overall as well as due to the more aggressive type as compared to other ethnic and racial groups.

The aggressive cancer is called Type 2 endometrial cancer, and it's difficult to treat. The researchers found by the end of the study, it had accounted for about a fifth of the cases of cancer investigated but nearly half (45%) of deaths.

Many gynecological cancers have seen improvements in treatments in the last 20 years, which have at least helped lower or stabilize death rates, but not so for uterine cancer. This suggests the need to look harder at and isolate efforts toward uterine cancer, particularly when regarding women of color contracting and being treated for it.

Researchers estimate that 65,950 new cases of uterine cancer will be diagnosed in the United States this year, with about 12,550 expected to die due to their cancer. There is no recommended screening test, though irregular bleeding (particularly after menopause) may be a sign. You may feel pain or pressure in your pelvis, but otherwise, symptoms of uterine cancer are slim and that makes it so hard to detect and treat.

The research team looked at cancer data in the U.S. for women who are 40 and older. They found that overall uterine cancer rates of death increased by 1.8% from 2010 to 2017.

When looking demographically, they found the annual rates increased 6.7% among Hispanic women, 3.5% among black women, 3.4% among Asian women and 1.5% among white women. They adjusted for hysterectomy rates as women who have had wombs removed do not get uterine cancer, and this stat varies by race.

Dr. Megan Clarke is with the National Cancer Institute and led the study that was published in the JAMA Oncology journal. She said that obesity may be a risk factor for less aggressive uterine cancer, but that they haven't found clear risk factors for the more aggressive kind. Clarke said that it's very puzzling and concerning that it's more common in women of color and that it is increasing for all ethnic populations of women. Dr. Clarke's prior research from 2000 to 2007 showed that white women had higher rates of uterine cancer, but in years past, that's been taken over and surpassed by women of color. She believes there are other factors than simple obesity or even disparity in health care, and plans to continue research into risk factors for all.