‘I question what I know’: Top cancer specialist Otis Brawley on valuing orthodoxy in medicine

Oncologist Otis Brawley has dedicated his career to advocating for orthodoxy in medicine. Now, he says, advances in cancer treatments and early-detection screenings are fast outpacing the medical community’s ability to assess them — warranting more caution lest doctors inadvertently cause more harm to cancer patients.

“I think we need to actually start policing ourselves better,” Brawley, a professor of oncology and epidemiology at John Hopkins University and former chief medical officer and executive vice president at the American Cancer Society, said at a STAT virtual event on Tuesday.

Brawley pointed out that a number of drugs for late-stage cancer patients that are FDA-approved do not yet have randomized control data to support them. Many of those drugs, he said, have received FDA approval because they can potentially increase patients’ median survival rates by three to four months. “One has to wonder, is the pain of taking the drug, including the financial pain, and side effects that come with it, worth the chance that you might have a three-month median survival increase?” Brawley asked. How to improve quality of life, he said, should remain an important consideration in the pursuit to extend the lives of cancer patients.

Similar concerns apply to cancer screenings, Brawley said, noting that with the development of several multi-cancer early detection (MCED) blood tests underway, “If we’re not careful, this is going to be the wild, wild west of screening.”

Brawley is an adviser to Grail, the largest MCED developer, and would not comment on specific products as a result. But he advised that in their current state, MCED tests should not be done in lieu of other standard screenings — particularly because there’s a risk of overdiagnosis, a phenomenon in which patients meet a pathological criteria for cancer, yet experience no symptoms or damage to their bodies. These patients could be encouraged to undergo unnecessary treatments for cancers that might never otherwise become a problem.

“We have a long history in medicine, going back to the Pap smear, where we have instituted screening without adequately assessing the test,” Brawley said, invoking other historical examples as precedents including chest X-ray screening for lung cancer in the 1960s and mammograms in the 1970s. The problems of overdiagnosis and overtreatment have led many medical professionals to conclude, “‘Let’s slow this down because we’re going too fast and we’re starting to hurt people,’” he said.

For decades, Brawley has been pushing back against the conventional wisdom to “find [cancer] early and cut it out.” In the 1990s, he began to question whether routine prostate-specific antigen (PSA) screenings were actually protecting men’s lives. “In metropolitan Seattle, the prevalence of men diagnosed with prostate cancer was higher than the prevalence of left-handedness,” he recalled.

It became apparent that some men risked undergoing treatment they did not need, which could be more harmful to them than the cancer itself. “In the 1990s, if you were diagnosed on Tuesday, you were told you need to have your prostate out by the end of the week,” said Brawley. Since prostate cancer screening guidelines have changed, the initial treatment for about half of men diagnosed with prostate cancer today is observation.

Now, as scientists edge closer to screening for cancer based on genetic risk factors, there is also a risk that people could enter into treatments for cancers they don’t end up developing in their lifetime. “We need to be very careful as we go forth with genetic testing,” Brawley said. “I’m very much in favor of studies to better figure out how to do it. We’re not ready to do it yet.”

Brawley also advised caution in the push to develop race-based cancer screening guidelines. “I’m just very, very concerned that that makes people think race equates with biology,” Brawley said. “The unintended consequence of focusing too much on race and ethnicity is, in the United States where we all see things through this racist lens, people tend to think that race determines things that it doesn’t really determine,” he added.

Rather than focus on racial differences in health that are, by and large, determined by socioeconomic factors, Brawley advised physicians to address health disparities by ensuring that everyone gets adequate treatment. He is frequently asked whether Black women should be screened for breast cancer earlier in life, starting at age 35. “But nobody ever asked me about the fact that 40% of Black women over 50 don’t get screened, period,” he said. “And if we could provide that 40% with adequate screening, adequate diagnosis, and adequate treatment, the number of lives that could be saved and the number of life years that could be saved are far greater than if screening works for Black women aged 35 to 44.”

Brawley further advised the medical community to be wary of making extrapolations beyond what is known from clinical trials. “If the patient doesn’t fit the clinical trial or is way out of qualification for going in the clinical trial, we shouldn’t treat them with the drugs in the clinical trial,” he said.

Throughout his 35-year career, Brawley said, his rule of thumb has been to abide by the advice he received from a Jesuit priest before he went to medical school: “‘Remember, there are things you know, things you don’t know, and things you believe. Doctors have this terrible problem of confusing what they believe with what they know.’

“I question what I know more than anything else,” Brawley continued. “Because oftentimes what I know, or what we in medicine know, turns out to be wrong.”