MANY women who have a breast tumor are told by their doctors that it's OK to leave the lump where it is, that it's unlikely to cause a problem.
For many tumors, that's true. But one particular type of breast lump -- called a papillary lesion -- should always be surgically removed, doctors now say.
A study in the March issue of Radiology found that papillary lesions can appear normal when biopsied using a needle but can actually be cancerous or precancerous.
The study is one of the largest to suggest that surgery is the best approach for all papillary lesions. Previous studies have produced mixed results on how doctors should best handle these tumors.
"With papillary lesion, it has been very controversial," says Dr. Cecilia L. Mercado, lead author of the study and an assistant professor of radiology at New York University Medical Center. "It's been up to the mammographer and surgeon to decide what to do."
Mercado estimates that these tumors are left alone in about half of all cases.
Papillary lesions are small collections of abnormal cells that arise in the ducts of the breast. When the lesions are near the nipple, they sometimes produce a discharge. These lesions are usually benign, but doctors remove them anyway to stop the discharge.
Lumps in the peripheral milk ducts are less predictable, Mercado says. These lumps are usually found during mammography, and many women undergo a needle biopsy to check for cancer. During a needle biopsy, a thin needle is inserted into the breast and a sample of the tumor cells is removed for analysis under a microscope.
With most breast tumors, such as a more common type called adenofibroma, a needle biopsy is reliable because the tumor contains the same type of cells throughout.
But the new study shows the sample taken from a papillary lesion is not always accurate. The sampled cells can be benign while other cells in the lesion can be cancerous or precancerous.
"When we do a needle biopsy, we may only capture the benign portion," Mercado says.
In the study, Mercado looked at 42 patients diagnosed with benign papillary lesions after undergoing a core needle biopsy. Of those, 36 women had the lesion surgically removed as part of the study to see if biopsy is reliable for this type of tumor. When the tumors were examined after surgery, nine were found to be precancerous or cancerous.
