Herceptin®

Herceptin is a new anti-cancer drug just approved in the US in the fall of 1998 for use against certain types of breast cancer.  It is the first of a new type of treatment; a genetically engineered, man-made cancer anti-body.  As such it is not a chemotherapy and does not have the side effects of chemotherapy.  The catch is that it only works for patients whose cancer cells are HER2/neu positive.  This mouthful means that it only works if the patient’s cancer has an excess of a specific protein present on its surface.  Apparently about 20% of breast cancer is HER2/neu positive.  The Herceptin anti-body, once injected into the blood stream, attaches itself to the cancer cells that are HER2/neu positive and once attached, the bodies normal immune system recognizes the cancer cells as bad and goes after them. Basically the attached man made anti-body marks the cancer cells for destruction in the same way that our own naturally produced anti-bodies do for infections.  This is great because one typically does not naturally produce anti-bodies to breast cancer as the cells are too similar to normal cells.  To determine if one is HER2/neu positive, one needs to have a pathology test done on a sample of cancerous tissue such as that removed during a lumpectomy (or perhaps even a sample from a biopsy, if there is enough).  The test done is sometimes called a DAKO test as this is the name of the kit used to do the test.  HER2/neu testing is not generally available in Canada.  HER2/neu is also called c-erb B2.  Apparently these are two different scientific names for the gene sequence relating to this special protein that is produced in excess.  I obtained samples of Dulce's tumor that had been removed a year before I found out about Herceptin.  Tumor samples are typically preserved in paraffin by the pathologists who examine them after surgery.  You can get them years later.  Unfortunately, in our case Dulce was HER2/neu negative and thus Herceptin was not an option.  But I personally know of patients with advanced metastatic breast cancer where Herceptin produced amazing results.  I would recommend that every breast cancer patient investigate whether Herceptin is an option.  Kevin...

I had Dulce’s lumpectomy sample tested in Seattle by
Dr. Rodney Schmidt
Pathology Department
University of Washington Medical Center
Seattle, Washington
Tel: (206) 548-6400  Fax: (206) 548-4928

Dulce’s oncologist in Seattle was:
Dr. Julie Gralow
Oncology Department
University of Washington Medical Center
Seattle, Washington
Tel: (206) 543-9598  Fax: (206) 616-8553

Herceptin is produced by the company Genentech:
Tel: (650) 225-1000  Fax: (650) 225-6000
Web: www.genentech.com
          www.genentech.com/pressrelease/1998/09_25_98.html