Biology doesn’t explain disparities in cancer treatment — racial bias does

Biology doesn’t explain disparities in cancer treatment — racial bias does
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The story was all too familiar.  

A patient is diagnosed with locally aggressive prostate cancer. A few days before the surgery, the patient does not show up for his preoperative visit. We call the patient.

“We noticed you didn’t show up for the pre-op, is everything okay?” “I am sorry, doc. Had to cancel — something came up,” he sighed.  “No problem. Should we reschedule the procedure?”

“To be honest, Doc, I am not sure if I can afford to miss work right now. The surgery is going to have to wait.”

In this story, our patient is black. He has insurance provided to him by his employer, but his position in the company is — as many Americans, unfortunately, experience — directly tied to his ability to work, and to work now. This episode represents an individual account that national-level disparities research often miss.


Next week will mark the twenty-fifth anniversary of the NIH Revitalization Act of 1993, a federal law that requires conducting subset analysis by race on clinical trials funded by the NIH.

Although this law was enacted in order to increase representation of women and minorities in clinical research (something it hasn’t been able to achieve), it serves as a reminder of how race- or biology-based frameworks do not explain the stark disparities prevalent in health care.

For far too long, cancer research on race-based disparities has focused on biological, or genetic, differences between black and white patients. As researchers, we are dismayed at how this discussion has a misplaced understanding of where disparities in cancer care arise from.

Research from our group and many others have demonstrated that most of these differences lie in the spectrum of income, insurance, and access to care inequalities, not in the biological differences among races. In the last decade alone, the gap in survival from prostate cancer may be widening, with black patients sharing a disproportionate burden of worse prognosis.

There are several reasons for this.

Clinical outcomes in any disease depend on the quality of care received by patients. Last year, a group of researchers in North Carolina investigated the care minority black cancer patients receive.

What they discovered was startling. Using quality metrics such as discussion of treatment options, comprehensive diagnostic workup, and receipt of treatment at a top-level institution, and radiation therapy for high-risk patients, they discovered that black cancer patients consistently received lower quality of care. We cannot expect better outcomes for patients that receive consistently inferior to standard care.

A remarkable observation is how usage of definitive treatment varies among black and white men with prostate cancer. “Definitive” treatment is a therapy that is given with a curative intent — which for prostate cancer is surgical removal of the prostate gland or some form of directed radiation therapy. In fact, research from our group has demonstrated that in more aggressive prostate cancers, black men are less likely to receive definitive treatment.

To be sure — black and white prostate patients may have disparate personal preferences when it comes to cancer care, but these minor differences do not explain the incredible gaps in care between these races.

A recent study found that nearly half of U.S. accredited institutions are more likely to treat white men with aggressive cancer than their black counterparts — how can this make any sense?

It is noteworthy that clinical outcomes for black prostate cancer patients are vastly different when socio-economic barriers do not impede access to care.

In equal-access settings, such as the Veteran Affairs health system, an investigation found no significant difference between black and white patients in the time that it takes from initial diagnosis of prostate cancer to definitive surgery. This study illustrates that equal access eliminates delays in timely access to comprehensive cancer care.

Another analysis from our research group revealed that even though elderly black Medicare beneficiaries were less likely receive high-quality care compared to their white counterparts, there were no racial differences in cancer-specific mortality, or even all-cause mortality.

This study also revealed how it is hard to argue that “genes” contribute towards worse outcomes, as black and white patients had equal outcomes when they had equal access to care in the form of Medicare coverage.

The black community is already at risk of developing a more severe form of cancer and inadequacies in optimal management abound, we must reconsider the basis for a narrative that suggests black cancer patients are genetically predisposed to worse outcomes. Evidence suggests that it is more likely a reflection of our own biases.

Several decades ago, it was commonplace to assert the inferiority of black Americans and other minorities with regards to educational capabilities or intelligence — often based on perceived genetic differences. The discrimination has not changed, only the labels have.

Junaid Nabi, M.D., MPH, is a senior project manager for research at the Department of Surgery, Brigham and Women's Hospital and a Research Fellow at Harvard Medical School. He is also a New Voices Fellow at the Aspen Institute, Washington, D.C. Twitter: @JunaidNabiMD. Quoc-Dien Trinh, M.D., is a urological surgeon and co-director of the Dana-Farber/Brigham and Women's Prostate Cancer Program. He is also an assistant professor of surgery at Harvard Medical School. Twitter: @qdtrinh.