Daniel O'Neil, MD

Daniel O’Neil, MD, MPH, is a medical oncologist who specializes in breast cancer.

“It’s incredibly rewarding to work with breast cancer patients,” Dr. O’Neil says. “I meet people during one of the most stressful moments in their lives, usually shortly after they've been diagnosed, and I have the opportunity to give them the information they need to make the best decisions about how to take care of their disease. I try to reassure them that they are making a good choice for themselves and for their families.”

Dr. O’Neil says he enjoys getting to know his patients and their families. “In many cases, breast cancer patients are cured completely. I get to see my patients for years afterwards as they've continued to live their lives and everything has returned to normal,” he says. “And even in cases where there is more aggressive or advanced disease, there is still an opportunity to help patients choose the right treatment to maintain their quality of life, to help them live with their disease for as long as possible, and to help them make good choices about what's important to them.”

At Smilow Cancer Hospital, a team approach is beneficial to patients, Dr. O’Neil says. “When you're being treated for breast cancer, there are the physicians you interact with directly, such as your surgeon, medical oncologist, and radiation oncologist. And then there are the doctors who are behind the scenes, like pathologists and radiologists, who interpret many of the tests that you're undergoing and are hugely important to your care,” he says.

Dr. O’Neil’s research is focused on understanding the quality of breast cancer care delivered in low- and middle-income countries. He is also interested in how HIV affects breast cancer mortality in women.