Paul
04-11-2004, 02:27 AM
Dear Jeanene,
If you click on the cross-link below, it will take you to an excellent discussion of the pros and cons associated with IHC and FISH testing. On page 3 (at bottom), I found the comments made by Dr. Dennis Slamon (whose research led to the discovery of herceptin)interesting. He is aware of clinical trials where patients were IHC +3 and FISH-negative, but responded to herceptin. He is also aware of clinical trials where patients were IHC +3 and FISH-negative, but did NOT respond to herceptin.
So, your situation has happened in the past. Based on my reading of the document, I would have your surgery sample retested by IHC WITH DIGITAL ANALYSIS (Digital IHC analysis helps cut down on human error in the lab as the results are computer analyzed) and again by FISH at a very well-respected pathology laboratory. You should also become familiar as to how your tumor samples were preserved (e.g., stained slides, or in a block preserved with formalin, or both, etc.)
Compare your results again after you're finished retesting. This issue is critical because your true HER-2 status will have an impact on whether you will receive herceptin, or how well you will respond once you are on it. I would definitely insist on retesting.
If you click on the cross-link below, it will take you to an excellent discussion of the pros and cons associated with IHC and FISH testing. On page 3 (at bottom), I found the comments made by Dr. Dennis Slamon (whose research led to the discovery of herceptin)interesting. He is aware of clinical trials where patients were IHC +3 and FISH-negative, but responded to herceptin. He is also aware of clinical trials where patients were IHC +3 and FISH-negative, but did NOT respond to herceptin.
So, your situation has happened in the past. Based on my reading of the document, I would have your surgery sample retested by IHC WITH DIGITAL ANALYSIS (Digital IHC analysis helps cut down on human error in the lab as the results are computer analyzed) and again by FISH at a very well-respected pathology laboratory. You should also become familiar as to how your tumor samples were preserved (e.g., stained slides, or in a block preserved with formalin, or both, etc.)
Compare your results again after you're finished retesting. This issue is critical because your true HER-2 status will have an impact on whether you will receive herceptin, or how well you will respond once you are on it. I would definitely insist on retesting.