Follow-up imaging for patients with benign breast biopsies can be safely done at 12 months rather than 6 months, when radiologic and pathologic findings are concordant, according to a study reported at the American Society of Breast Surgeons Annual Meeting in Chicago.¹

Current guidelines from the National Comprehensive Cancer Network (NCCN) recommend that such patients undergo follow-up imaging at 6 to 12 months. However, the value of the shorter-term interval is questionable, said Demitra T. Manjoros, MD, an oncology fellow at the Comprehensive Breast Center, Bryn Mawr Hospital, Bryn Mawr, Pennsylvania, who presented the findings.

“Our data do not support the routine use of short-term interval imaging following benign concordant breast biopsy,” Dr. Manjoros said.

Study Details

“It’s been difficult to know what the correct interval imaging is. Our study intended to determine if there is value to imaging at 6 months when you have benign concordant findings, or whether we are overimaging patients,” she told The ASCO Post.

Dr. Manjoros and colleagues reviewed their experience at Bryn Mawr Hospital in 2010 with image-guided breast biopsy over a 12-month period. They evaluated the cancer yield and cost associated with imaging performed less than 12 months after a benign concordant biopsy in 689 patients who underwent image-guided biopsy (stereotactic, ultrasound-guided, or magnetic resonance imaging [MRI]-guided).

Of the 689 patients, 188 cases were malignant (27.3%), 3 indicated nonbreast pathology (0.4%), and 498 (72.3%) were benign. Of the 498 patients with benign findings, 44 (8.8%) underwent surgical excision secondary to atypia, papillary lesions, discordant pathology, or other benign findings. Of this patient subset, 8 lesions were discordant. Of the 454 benign biopsy patients who did not have excisions, 3 lesions were discordant.

The pathologic findings for these 11 discordant lesions included benign conditions in 7, high-risk conditions in 1, and invasive cancer in 3 cases.

Of the 337 concordant patients, 169 patients had a total of 204 imaging studies done in less than 12 months, and these were analyzed for this study. Of these 169 patients, biopsy findings were fibrocystic change in 39.6%, benign tissue or cyst in 37.9%, fibroadenoma in 17.8%, papillary lesion in 3.6%, atypia in 0.6%, and “other” condition in 0.6%.

Of the 169 patients, 128 were BI-RADS 2 while the rest were mostly BI-RADS 1 and 3 (see box). Five (3.0%) had suspicious (BI-RADS 4) findings on follow-up imaging, 2 away from the original biopsy site and 3 at the biopsy site.

Only One Cancer Identified

Ultimately, only one breast cancer was identified, representing 0.6% of all benign concordant patients undergoing interval imaging, Dr. Manjoros reported. This occurred in a patient imaged less than 12 months from biopsy; none occurred among patients who were imaged more than 12 months postbiopsy.

“Also, no cancers were identified with interval imaging after stereotactic or ultrasound-guided biopsy,” she added.

The one missed cancer occurred in a 39-year-old woman with a history of left-sided breast cancer 4 years prior who was noted to have a 6-mm area of enhancement in the left breast on screening MRI away from the lumpectomy cavity. The initial MRI-guided biopsy was benign and concordant but the 6-month follow-up MRI showed an increased area of enhancement; needle-localized excision demonstrated invasive cancer.

“This patient was a higher-risk patient and we believe she would have been identified regardless,” she said.

She said another interesting finding was the high rate of cancer detection among patients whose lesions were discordant. “We had 11 discordant lesions, and of these, 3 (27.3%) were upstaged to invasive cancer, vs 0.6% in the benign concordant group,” she noted.

The cost of finding one cancer among these 169 patients with benign concordant biopsies was $192,745 (by institutional billing charges). “This is the cost for one institution over 1 year, which if multiplied across the country amounts to a lot of health-care dollars,” said senior author ­Andrea V. Barrio, MD, of MLHC Breast Surgical Specialists in Bryn Mawr.

Take-home Message

Dr. Manjoros said the take-home message is that routine use of interval imaging less than 12 months after biopsy is unnecessary, though the shorter interval is warranted in select cases.

“We are taking away the routine recommendation for evaluation and saying that in certain conditions we don’t need to do it,” she said. “Selective use should be considered when it is difficult to confirm lesion retrieval.”

Dr. Barrio emphasized the need to correlate the imaging and histologic findings. “And you need to make sure you have a system set up so radiology and pathology can communicate for every biopsy, so you can say a lesion is discordant or not,” she said. Concordance assessment, in fact, should probably be a quality measure, she added. ■

Disclosure: Dr. Manjoros reported no potential conflicts of interest.

Reference

1. Manjoros DT, Collett AE, Alberty-Oller JJ, et al: The value of six-month interval imaging following benign radiologic-pathologic concordant minimally invasive breast biopsy. American Society of Breast Surgeons Annual Meeting. Abstract 125. Presented May 2, 2013.