Among young women diagnosed with breast cancer, black and Hispanic patients were more likely to wait weeks for treatment, in a new study from California.
Researchers found treatment delays were also more common among poor women and those without private insurance - and that a woman's chance of surviving at least five years after cancer surgery was lower when it was put off.
"This study adds to a number of other studies that have also documented treatment delays that are patterned by race or socioeconomic status," said Sam Harper, who has studied racial differences in breast cancer diagnosis and survival at McGill University in Montreal.
"What the study does identify is that there are differences… the study really can't tell us much about why that's occurring," he told Reuters Health.
For example, Harper said, it's possible minority patients are sicker than whites, on average, and doctors wait to treat them for good reason. Or, poor women may have more trouble taking time off from work and getting to their appointments.
"Of course, there's the potential for discrimination in treatment," said Harper, who wasn't involved in the new research. "I think that's what's most concerning about findings like this."
For their study, Hoda Anton-Culver from the University of California, Irvine, and colleagues analyzed records of 8,860 women age 15 to 39 that were diagnosed with breast cancer in 1997 through 2006. Although cancer is rare in that age group - accounting for 5 to 6 percent of all breast cancers - it's typically more aggressive than in older women, the researchers noted.
They found the time between diagnosis and treatment - whether surgery or chemotherapy - was delayed more than six weeks in 8 percent of white women and 15 percent of both Hispanic and black women.
Likewise, between 9 and 10 percent of privately-insured women had their treatment delayed more than six weeks, compared to 18 percent of those who had no insurance or were covered by Medicaid.
And for women treated with surgery, in particular, outcomes were substantially worse after a long delay: 80 percent of those women lived at least five years after surgery, compared to 90 percent of patients who waited less than two weeks for treatment.
Anton-Culver said younger women are a unique group because they're often in between insurances or in between jobs.
"Our healthcare system does not allow for access to healthcare by all people in the same manner," she told Reuters Health.
"Without having a real standard of care (for type of treatment and time to treatment) that the healthcare system is accountable for, you will see those differences."
Differences for those on Medicaid?
In another study published concurrently in JAMA Surgery, researchers from the University of Toledo Medical Center found women with early-stage breast cancer had larger tumors at diagnosis, and were more likely to be treated with breast-removing surgery, if they were covered by Medicaid.
Sixty percent of those women had a mastectomy, compared to 39 percent of patients with private insurance. The National Institutes of Health endorses breast-conserving surgery - rather than mastectomy - for early-stage breast cancer, the team led by Dr. Linda Adepoju noted.
The studies are consistent with prior research which has shown, for example, that black women are more likely to die of breast cancer - in part due to segregation and lower neighborhood and family incomes.
However, with so many questions about the potential causes behind disparities in cancer treatment and outcomes, it's hard to know where to go next, Harper noted.
"It really should push us to try to get at some of those questions for understanding: how much of these differences may be due to discrimination, or where people live and access to treatment?" he said.