AB031. SOH25_AB_090. Comparing vacuum-assisted excision (VAE) and diagnostic excision for B3 breast lesions: a study of diagnostic yield and patient outcomes

Background: “B3” breast lesions (lesions of uncertain malignant potential) pose a diagnostic challenge, traditionally further assessed by diagnostic surgical excision. Vacuum-assisted excision (VAE) offers a less invasive alternative. This study compares diagnostic yield, clinical outcomes, and upgrade rates between VAE and excisional biopsy for B3 lesions, following introduction of VAE into our unit.

Methods: A retrospective review of 200 patients diagnosed with B3 lesions via the national breast screening programme was conducted. Data included patient demographics, lesion characteristics, procedure type, upgrade rate to malignancy and need for further surgery. Excisional biopsy was performed for 175 lesions; VAE for 27 lesions. VAE was selectively performed on lesions with no evidence of atypia on core biopsy.

Results: Excisional biopsies had a mean specimen weight of 25.4 g, significantly larger than the 3.98 g for VAE. Upgrade rates to malignancy were 6.2% for invasive carcinoma and 10.2% for ductal carcinoma in situ following diagnostic excision. 92.6% of excisional cases required no further surgery. After VAE, atypia was detected in 11% with no upgrade to carcinoma/carcinoma in situ. Only one patient (3%) proceeded to diagnostic surgery.

Conclusions: VAE is an effective and minimally invasive option for management of B3 breast lesions, with removal of smaller tissue specimens than surgery. Upgrade rates following surgery are low, meaning there is scope for broader use of VAE in the management of B3 lesions and this is internationally accepted. Our data provide confidence in expanding use of VAE in our unit, which should reduce the number of patients requiring diagnostic surgery following breast screening.

Keywords: Breast lesions; B3 lesions; vacuum-assisted excision (VAE); diagnostic excision; malignancy detection