Outcome of a new patient pathway for managing B3 breast lesions by vacuum-assisted biopsy: time to change current UK practice?

Aims B3 lesions of the breast represent a difficult management dilemma. The umbrella term ‘B3’ incorporates lesions with little associated malignancy risk as well as lesions with significant risk of concurrent neoplasia. Diagnosis of B3 lesions in screening populations is largely made on needle core biopsy, which provides little tissue to adequately diagnose pathologically diverse lesions. The advent of vacuum-assisted biopsy (VAB) provides the multidisciplinary team with a more representative pathology sample to direct management. Methods In this unit, in 2009, a pathway to guide management of B3 lesions detected on needle core biopsy in screening patients was implemented to assess whether VAB was a safe and viable alternative to surgery in selected cases. Here we present the 5-year follow-up results of this pathway. Results 398 patients with B3 lesions were suitable for this pathway, of which 321 went on to have second-line VAB. 24% of these patients subsequently required surgery for malignancy or ongoing concerns, and thus 245 avoided surgery being subsequently referred for 5-year mammographic surveillance or back to screening. Median follow-up was 3 years (IQR 2), and no cancers were detected at the original B3 site during follow-up. Conclusions We have demonstrated here that with large volume tissue sampling for indeterminate lesions of the breast surgery can be safely avoided in selected B3 lesions with and without atypia.