Question: My breast biopsy report said I have ductal carcinoma in situ, high grade with comedonecrosis; estrogen and progesterone receptor positive and her-2/neu 3+ over-expressed. My doctor referred me to a radiation therapy doctor and recommends I take Tamoxifen but not chemotherapy because the her2/neu result shouldn’t have been run on my cancer. I’m confused.

Answer:  Your doctor is correct.  HER2 testing is only performed on invasive carcinomas not on carcinoma in situ so this test should not have been run.