BOSTON -- Breast cancer kills an estimated 40,000 American women each year but in the developing world the numbers are more stark, something the new dean of Harvard's School of Public Health learned first hand firsthand.

In October 2007, Dean Julio Frenk's 41-year-old wife was diagnosed with breast cancer after abnormalities were detected on her first mammogram. The couple was living in Mexico at the time. Frenk had just completed six years as Mexico's Minister of Health.

"Suddenly I was on the other side of the table," said Frenk. "I was now the relative of this person I loved very much who had just been given this terrible diagnosis."

"Women have a tremendous fear of what breast cancer can mean, which is mastectomy. Rejection can be common," said his wife, Felicia Knaul, a respected public health researcher in her own right.

While undergoing chemotherapy and multiple surgeries to fight her own cancer, Knaul also combated social stigmas against the disease in her adopted country of Mexico.

She estimates that only between 5 and 10 percent of breast cancers among women in the developing are caught early. The percentage is even lower among poor women.

A recent study showed that only one in five women over the age of 40 had received either a mammogram or clinical breast exam within the past year.

"Julio has spoken about the cancer that goes alongside breast cancer. The cancer of machismo," said Knaul.

NewsCenter 5's medical editor, Dr. Timothy Johnson, asked Frenk what it has meant to him to stand by his wife's side during her illness.

"It's brought us closer than ever, actually," he said.

Knaul went public with her story in Mexico, where her story and her research showing that breast cancer had surpassed cervical cancer as the top killer of women in that country, helped make breast cancer a government priority.

Frenk said his priorities in his new post as the dean of Harvard's School of Public Health are framed in part by his family's experience. He said all public health experts need to think globally and find solutions. The key, Frenk says, is once those public health solutions are identified, the entire population must have access.