Finding and treating hidden 'occult' breast cancer presents challenge for patients and doctors

Fewer than 1 percent of breast cancer patients have no actual symptoms in the breast. This condition is called occult breast cancer. (Baltimore Sun video)

Mary Brune crossed her arms while at work one day in 2014 and found a lump under her right armpit.

Brune, a nurse who lives in Kingsville, hadn't felt any lumps in her breast, so she didn't think it could be breast cancer. She figured it was probably an abscess but made an appointment with her doctor to have it checked out.


Her doctor ordered a mammogram, which also found no abnormalities in her breasts. But an ultrasound of her underarm told a different story. It showed an enlarged lymph node, which her doctor biopsied and confirmed was cancerous.

Brune became one of the fewer than 1 percent of breast cancer patients diagnosed with breast cancer who have no actual symptoms in the breast. The condition is called occult breast cancer.


"I really was shocked to find it was breast cancer," Brune said. "It just felt strange. If I had gone for my routine mammogram nothing would have shown up."

Because occult breast cancer is so rare there have been few large studies conducted on the disease. But doctors have been able to use large medical databases to learn more about this type of breast cancer. The studies have not shown patterns indicating that any particular racial or age group is more likely to get this form of breast cancer, or that there is a genetic component, but the research has given doctors more insight into how to treat it.

Oncologists aren't sure why some cases show no signs in the breasts. It could be that at one point there was a visible cancer in the breast that the body fought off but not before it spread to the lymph nodes.

"The theory is that perhaps the immune system obliterated the cancer enough so that it is not visible anymore," said Dr. Emily Bellavance, a breast surgeon at the University of Maryland Medical Center. "Presumably something was there and perhaps the body's immune system took care of the initial site but couldn't handle the disease in the lymph nodes."

Breast cancers can spontaneously regress before they are detected, said Dr. David Euhus, director of the Johns Hopkins Breast Center.

"This is all theoretical, but there could be that there was a cancer that grew up and got mature enough to metastasize to the lymph nodes and then for some reason it regressed," he said.

Patients with no obvious signs of cancer in the breast are given an MRI to search for any residual cancer cells. In Brune's case, the MRI, which gives a closer look at the breast tissue, still found no cancer.

"We do the MRI to see if we can find the cancer," Euhus said. "In a large number of patients we won't find it."

Sometimes, occult breast cancer patients get a mastectomy, or removal of the breast tissue and lymph nodes, as part of their treatment. Signs of cancer can sometimes be found in the tissue.

Such cells were found after doctors performed an MRI on Linda Jones Hall, a 75-year-old retiree who lives in Lexington Park.

When Jones Hall was diagnosed with breast cancer last year, there were no lumps in her breast. A mammogram showed an enlarged lymph node, which an ultrasound confirmed. The MRI found two tiny lumps in the breast that were sent for a biopsy and found to have cancer.

Because the MRI eventually found signs of cancer, Jones Hall's case might not be considered a "true occult cancer," but still points out the problems with cancers not seen immediately in the breast, Bellavance said.


Jones Hall has dense breasts, which can make it more difficult to find lumps. She once had a false positive — where tests found cancer but later were proven to be wrong. Because of this, she is extra diligent about getting mammograms.

"Thank goodness for sharp radiologists realizing something was wrong, because it didn't show in the breast at all," said Jones Hall*.

There is some debate among oncologists about whether women with occult cancer should get mastectomies.

Bellavance was among a team of researchers who looked at treatment of occult cancer using data from the National Cancer Database, a clinical oncology database sponsored by the American Cancer Society and American College of Surgeons. One of the factors they looked at is whether women with occult cancer needed to get mastectomies.

The researchers looked at more than 1,200 cases of women with the disease from 2004 to 2013. They found proof that radiation and lymph node removal, without a mastectomy, was a good treatment option.

"This allows women, even though something started in their breast, to still keep their breasts," said Bellavance, who is also an assistant professor of surgery at the University of Maryland School of Medicine. "This would be considered a reasonable option."

One doctor recommended that Jones Hall* have her breast removed, but Dr. Bellavance convinced her that keeping her breasts also was an option.

In March, doctors removed lymph nodes from Jones Halls' right armpit as well as the tiny lesions from her breast. She had chemotherapy and is finishing up radiation.

At first, Brune wanted a mastectomy to get rid of any possibility of the cancer reoccurring. Dr. Bellavance convinced her that occult cancer could be treated without removing the breast.

She underwent chemotherapy first and then had lymph nodes removed. She also received radiation treatment. Brune has been cancer-free for nearly three years.

Brune had planned on getting perfect-sized breasts — perky C-cups — after the mastectomy, but she said she is just grateful for doctors detecting the cancer and treating it successfully without removing her breasts.

"I could be in a much worse position," she said.

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