Imaging surveillance is an acceptable alternative to surgical excision in patients with benign papilloma, diagnosed at breast core biopsy without cell abnormalities, a new study shows.

The study, conducted at the Breast Health Center of California Pacific Medical Center in San Francisco, included 119 papillomas diagnosed at core biopsy without abnormal cells.

Imaging follow-up of a minimum of two years without surgical excision was performed on 66 lesions; no cancer was found in this group, said Jessica Leung, MD, FACR, lead author of the study.

Surgical excision was done on the remaining 53 lesions, with 50 of those being benign. Ductal carcinoma in situ was diagnosed in the remaining three lesions, she said.

The "histological upgrade rate" (the core biopsy indicated the lesion was benign, but the surgical excision found cancer) was 2.5%, said Dr. Leung. This upgrade rate "approximates the 2% probability of malignancy that is widely accepted for these types of probably benign lesions," she said.

"Currently there is disagreement over whether cancer can be reliably excluded by breast core biopsy," said Dr. Leung. "The benefit of surgical excision is definitive tissue diagnosis and exclusion of cancer. The benefit of imaging surveillance is that it obviates unnecessary surgery, with its associated morbidity for nonmalignant lesions," Dr. Leung said. "This study provides evidence that imaging surveillance is appropriate for these patients," said Dr. Leung.

The incidence of benign papillomas without abnormal cells is uncommon --about 1.4% of imaging-guided core biopsies, noted Dr. Leung. Nevertheless, given the total number of core biopsies performed, the number of benign papillomas diagnosed is sufficiently high to warrant an evidence-based approach to their management. Papillomas are usually histologically complex lesions that are associated with a high degree of abnormal cells, she said.

The study is being presented May 3 at the American Roentgen Ray Society Annual Meeting in Vancouver, Canada.