Pathology of breast carcinoma.

The pathologist examines biopsy material obtained at surgery or preoperatively by core biopsy to make a definitive diagnosis of malignancy and to determine the type and grade of the tumour. Additional prognostic information is provided to the clinician, and this includes the true tumour size and the relative contribution of the in situ and invasive components. Other important factors include multifocality, vascular invasion and the presence and extent of axillary nodal metastases. For optimal use of this important information, close cooperation between the members of the multidisciplinary team is essential.