Abstract
The characteristics of a breast tumor can usually be ascertained by core biopsy prior to treatment. We compared pathologic diagnoses based on preoperative biopsy with those after surgery in 132 breast cancer patients. Though high ER and PR correspondences between surgical and biopsy specimens were confirmed, the rate of HER2 correspondence was only about 70%, tending to be lower in surgical than in biopsy specimens. This discordance might be explained by low dye uptake in surgical specimens, due to unstable fixation as compared with biopsy. There was no difference in pathologic findings, regardless of whether chemotherapy had been administered. Biopsy and surgical diagnoses must be carefully evaluated when there are discordant findings, as tumor background factors can vary markedly.
