Multicentric breast cancer is thought to be a contraindication for sentinel-node biopsy by most clinicians. In a prospective study we took sentinel-node biopsy samples from 19 patients with multicentric invasive breast cancer with use of a blue dye and radiolabelled colloid mapping technique at the subareolar injection site. All patients underwent complete axillary dissection after sentinel-node biopsy. Nine patients had tumour-free and ten had metastatic sentinel nodes. The sentinel-node status was in concordance with the axillary sample in all patients. Sentinel-node biopsy might become an alternative to complete axillary dissection in patients with multicentric breast cancer with clinically negative lymph nodes.