Last week saw some good news about cancer from the American Cancer Society’s (ACS) annual checkup report—a 25-year decline in cancer rates and a 27 percent drop in the overall cancer death rates in the United States.

That’s approximately 2.6 million fewer cancer deaths between 1991 and 2016. Early detection and optimal treatment get credit from the ACS, along with reductions in smoking rates, for declines in lung, breast, prostate, and colorectal cancers.

“The decline in cancer mortality over the past two decades is primarily the result of steady reductions in smoking and advances in early detection and treatment, which are reflected in the declines for the four major cancers,” said Rebecca Siegel, Scientific  Director, Surveillance Research for the American Cancer Society, and the lead author of the study.

But the news was not nearly as good low income people and people of color. The cancer death rate in 2016 was 14 percent higher in African-Americans than in whites, although that gap has narrowed from a peak of 33 percent in 1993. “Information about cancer prevention, detection and treatment is lower in underserved communities, which we think accounts for much of the gap,” said Cary Presant, an oncologist at City of Hope Hospital and a former president of the American Cancer Society’s California Chapter.

People living in the poorest counties in the U.S. are more likely to smoke and be obese, both risk factors for cancer. Between 2012 and 2016, death rates from cervical in the poorest counties were double those of wealthier counties. Rates were 40 percent higher for male lung and liver cancers compared with the richest counties. Poverty is associated with lower rates of routine cancer screening, later stage at diagnosis, and a lower likelihood of getting the best treatment, key factors in why cancer has not had as a precipitous drop among people of lower socioeconomic status.

California Data Shows Similar Disparities

The ACS report did not break out state specific data, but it did find that socioeconomic inequalities are widening, with residents of the poorest counties across the country being affected by the most preventable cancers, including lung and cervical cancer.

A 2017 report from the California chapter of the ACS did have more state specific findings:

• Black and non-Hispanic white men with twelve years or less of education in California are almost three times more likely to die of all cancers than men with a college education and four to five times more likely to die of lung cancer.
• Hispanic women are more likely than other women to die of cervical cancer despite the introduction of the HPV vaccine, which has reduced rates of the cancer in other groups.
• New immigrants may harbor infections from their home countries which can increase rates of stomach and liver cancer.
• Barriers to improved cancer outcomes include poor or no health insurance, low health literacy and access barriers including no or limited transportation.

The California report also notes discrimination as a factor which can result in poor people and people of color receiving poor quality care. According to the report, “Racial and ethnic minorities tend to receive lower quality health care than whites even when insurance status, age, severity of disease, and health status are comparable.”

Roshan Bastani, Director for Disparities and Community Engagement at the Jonsson Comprehensive Cancer Center at UCLA, agrees that discrimination is a likely contributor to the observed differences. “However,” said Bastani, “this is very hard to measure. And in most cases it is unlikely to be a deliberate decision to provide sub-standard care to ethnic minority or poor patients, but rather based on perceived stereotypes and assumptions on the part of providers that result in systematically poorer care.”

New Initiatives in California to Lower Cancer Disparities in California

New initiatives have been launched in the state in the last few years to reduce racial and socioeconomic disparities in cancer.

For example, Roshan Bastani said UCLA has moved from taking an individual patient approach to taking a community approach when it comes to cancer prevention. “We are focusing on the environment people are in and working to change it as needed so that the healthy option is the default option.” Projects include working with community centers to ask all women patients whether they’ve had, if age appropriate, an HPV vaccine. They also ask about pap smears, which can detect cervical cancer before symptoms appear.

In 2016, the San Francisco Cancer Initiative (SF CAN) a collaboration among UC San Francisco, the City and County of San Francisco, the San Francisco Department of Public Health and health care and community organizations was launched to help reduce cancer disparities in the state and become a model for other cities. The initiative has begun working with dozens of community organizations and has published a blueprint for other cities to follow.

Efforts in the state also include research into chronic stress as a risk factor for cancer. At UCSF a new study investigating prostate cancer deaths by race has found that African-American men have twice the chance of dying from low-risk prostate cancer than men of other racial and ethnic groups, even after adjusting for socioeconomic status.

UCSF is one of four National Cancer Institute cancer centers in the U.S. conducting a study of 10,000 African-American men with prostate cancer. Researchers will investigate environmental and genetic factors linked to the aggressiveness of prostate cancer in African-American men.

And while most mice studies on cancer use tumor cells from white men, Bastani points to a study among four UC medical centers. Sixty percent of the tumor cells studies in mice in the study will come from members of minority groups and those cells will be compared to ones from white subjects to see if the researchers can tease out biologic differences that can account for differences in the cancer.

No one effort will solve the cancer disparity issue, researchers said. “Given the large size and tremendous socioeconomic diversity of California, efforts to reduce cancer health disparities in the state will likely require collaboration between state and local health departments, safety net clinics, and community institutions such as churches and schools,” said Beth Glenn, Associate Director of the UCLA Kaiser Permanente Center for Health Equity.