Positron emission mammography: diagnostic imaging and biopsy on the same day

The purpose of this study was to determine the feasibility and potential advantages of performing positron emission mammography (PEM)-guided biopsy after diagnostic PEM on the same day.

A prospective study included patients with highly suspicious breast lesions identified at mammography or ultrasound (index lesions) and requiring biopsy. Diagnostic PEM was performed with IV injection of 10 mCi of (18)F-FDG. When possible, PEM-guided biopsies were performed on both the index lesion and the additional suspicious PEM-visualized lesions using the biopsy navigation accessory. All index lesions and occult malignant lesions detected with PEM were surgically excised and correlated with biopsy results. Radiation doses to medical staff were recorded.

The study included 20 patients in whom 26 of 27 lesions (96%) were adequately visualized to allow PEM-guided biopsy, which was performed on 24 of the 26 lesions. Twenty-one of the 24 (88%) biopsies had concordant results: 17 malignant tumors, one high-risk lesion, and three benign lesions. Three of 24 (13%) PEM-guided biopsies had discordant results, for which ultrasound-guided biopsy was performed. Additional occult malignancy was identified in 3 of 19 breast cancer patients (16%), resulting in two wide local excisions and one mastectomy. Staff doses ranged from 0.8 to 2.0 mrem (0.008-0.02 mSv) per case.

Same-day PEM-guided biopsy is feasible for most patients, decreases the radiation dose to both the patient and the medical staff (compared with returning for biopsy another day), and expedites the patient's preoperative staging workup for cancer.