More than 40% of responding adults who were unemployed reported that they did not have health insurance, compared with just 10% of those who had a job, the data showed.
Compared with those who were employed at the time of the study, fewer unemployed adults indicated they were up-to-date on recommended screening for breast, cervical, colorectal and prostate cancers.
For example, 68% of unemployed adults had been screened for breast cancer versus 78% of those currently working, according to the researchers.
And, screening rates for colorectal cancers, including colon cancer, were lower among the unemployed, at 42%, than the employed, at 49%.
"People who were unemployed at the time of the survey were less likely to have a recent cancer screening test and they were also less likely to be up-to-date with their cancer screenings over the long term," study co-author Stacey Fedewa said in a press release.
"This suggests that being unemployed at a single point in time may hinder both recent and potentially longer-term screening practices," said Fedewa, a senior principal scientist at the American Cancer Society.
Not undergoing routine screening for cancer can increase a person's risk of being diagnosed with late-stage cancer, which is more difficult to treat than cancer that is detected at an early stage.
About 30 million people in the United States do not have health insurance, the Department of Health and Human Services estimates.
Screening guidelines differ by type of cancer.
For example, the Centers for Disease Control and Prevention recommends that adults undergo screening for colon cancer, via colonoscopy, starting between age 45 and 50.
It also advises women to get screened for cervical cancer every three years, starting in their 20s, while they should undergo mammograms between age 50 and 74.
Prostate cancer screening recommendations are less clear.
For this study, Fedewa and her colleagues analyzed information from adults under age 65 who responded to the 2000-2018 National Health Interview Survey, a nationally representative annual survey of the United States population on health and insurance status.
Among the unemployed, 79% had been screened for cervical cancer, compared with 86% of those currently working, the data showed.
Similarly, 25% of the unemployed said they had been screened for prostate cancer, while 36% of the employed had done so.
All differences in cancer screening rates were eliminated after the researchers accounted for health insurance coverage, highlighting the importance of insurance coverage for enabling individuals to receive recommended cancer screening tests, they said.
"Our finding that insurance coverage fully accounted for unemployed adults' lower cancer screening utilization is potentially good news, because it's modifiable," Fedewa said.
"When people are unemployed and have health insurance, they have screening rates that are similar to employed adults," she said.