The Clinical Importance of the Heterogeneity of HER2 neu.

We report on a patient with breast cancer in whom there were areas of the tumor that were 3+ positive and negative for HER2 neu by immunohistochemistry, adjacent to each other. Depending on the area tested the results were completely different. The clinical implications are important.

American Society of Breast Surgeons MammoSite Radiation Therapy System Registry Trial: ductal carcinoma-in-situ subset analysis--4-year data in 194 treated lesions.

Background: A subset analysis of the American Society of Breast Surgeons (ASBS) Registry Trial of patients with ductal carcinoma-in-situ (DCIS) was performed to compare results to patients receiving accelerated partial breast irradiation (APBI) for invasive tumors and to results in patients with DCIS receiving whole breast irradiation.

Methods: One hundred ninety-four cases of DCIS were identified from a total of 1,449 cancers treated on the ASBS Registry Trial. Details of the trial are previously published.