Thread: Mast cell tumor
View Single Post
Old August 4th, 2009, 10:27 AM
Dr Lee's Avatar
Dr Lee Dr Lee is offline
Senior Contributor - Expert
Join Date: Jun 2007
Location: East Coast
Posts: 1,058
Originally Posted by SuperWanda View Post
...would not have been able to remove the 2-3cm of tissue it sounds like they recommend taking.

I just wish I could go back in time and have it removed earlier but I suppose that may have not changed much if the biopsy was still inconclusive.

Dr. Lee - do you know if we are in a worse state now that the tumor has been disturbed than if we had just left it?

This was a tumor that has grown very slowly over a year - it was about 8-9mm when it was recently removed. I have read that ones that grow very slowly may be more benign than the ones that come on more aggressively.

I will have to talk to the vet more about the pathology report but I imagine the margins of the tumor are "dirty" as it was removed with no extra tissue.

That is a most touching picture. She looks like a great companion. Also you cannot blame yourself for not being more aggressive earlier. It as difficult to decide to put your best friend through surgery if you are not sure it is warranted. You had tried to biopsy it and the results came back inconclusive.

The question as to it being in a worse state or not. This is a theoretical situation. There is a theory that if you inflame certain types of cancers, that it might lead to metastasis. There is not a direct way to prove that in a particular patient.

I also do not know that the allergic reaction one week ago was related to the MCT. I would be less likely to attribute it to the MCT. Because MCT do secrete histamine, then when veterinarians are worried about a MCT in surgery, they might often preload the pet with an intravenous injection of benadryl prior to surgery. During surgery the MCT has the potential to release massive levels of histamine. However once those cells have been removed from the body, they can no longer release histamine into the body and histamine has a short half life. It could not show up a week later. Typically from the release of histamine to the onset of clinical signs - you are talking about minutes, not days.

This leads me to your other question regarding the margins. Often a 2-3 cm margin is not possible. This does not mean that the margins are necessarily dirty. For a 2cm margin, the 2 centimeters is read out as 'normal' tissue. This is to hopefully catch cancer cells that might not be seen. However in many cases 2mm of clean tissue might be sufficient. If we are unable to obtain a 2cm margin in a cancer type where such a margin is recommended then we there are the options of radiation therapy, additional surgery or sometime cryotherapy. So - in aggressive cases 2-4 cm margins are recommended but it does not necessarily mean that a margin less than that is absolutely ineffective.

As BenMax asked about a cure.... Honestly I do not know enough about your case and I am also not an oncologist. I wish I could give you these answers but can best recommend that you talk to an oncologist. Also - I would try not to blame yourself - I am sure she does not.
Christopher A. Lee, D.V.M., C.V.L.S.
Promoting surgical options and pet comfort through the use of lasers.
Reply With Quote