Mast cell tumor

[SuperWanda]

Our 10 year old husky cross had a small lump removed from her nose last week. A week after the surgery she started having an allergic reaction with facial swelling and hives. She was injected with steroids/benadryl and the reaction subsided but returned so she is now on benadryl every 8 hours.

Today we have found out that the lump was a mast cell tumor (intermediate grade) - we tried to have it biopsied before the surgery but the results were inconclusive so it was just removed with no extra tissue removed around it - which apparently you should do if you know it is a mast cell tumor.

These results also explain why she has had an immune response as the tumor or remaining cells produce histamine.

We haven't discussed these results with our vet - she will be back from holidays in a few days - but what I have read really worries me.

Last year, our other dog was diagnosed with a sarcoma in her leg and we had it removed only to find that the pathologist was mistaken when he looked at the biopsied cells and it was just a benign fibroid so I have been trying to not worry so much about lumps and bumps - only to find out these results.

Just thought I'd see if there are any others here who have experienced this type of tumor?

Thanks.

[rainbow]

SuperWanda, I am so sorry to hear the news and, it's really too bad that the vet didn't remove a safety margin of the surrounding tissue. :sad:

I don't have any experience with this type of cancer but just wanted to wish you all the best for your girl and hope something more can be done.

[rainbow]

I just googled and found this website and there's lots more links at the bottom of the page but perhaps you have already read it ....

http://www.kateconnick.com/library/mastcelltumor.html

[BenMax]

I have sadly. My very first rescue cat that I adopted to my parents 15 years ago was diagnosed last November. It is a horrible tumour and they seem to appear and erupt over night. Sadly, at age 16 just 3 weeks ago my mom and I helped him over the bridge. (RIP little man).

It is a horrible tumour(s) however they are not painful but if they erupt there is dicomfort which is remedied with medication.

I wish you the very best. All I can recommend is to monitor the tumours, be aware of new growths and keep in touch with the vet on a regular basis which I am certain from what you write - you are doing just that.

My heart is so with you on this.

[SuperWanda]

Thank you.

I feel very worried about it. We noticed it last year and didn't rush to have it removed. We tried to biopsy it but the results were inconclusive. We decided to keep an eye on it and as it was still slowly growing we went ahead with the removal but no one, including our vet was all that worried about it. More of a cosmetic issue it seemed.

I am now feeling terrible about waiting so long when it could have potentially been removed a lot earlier perhaps when it was only a stage 1.

Now, the surgery has disturbed it which I feel may be even worse.

I guess I need to wait and get more information from the vet but everything I read does not seem positive.

[BenMax]

SuperWanda - don't blame this on yourself. Mass Cell Tumour does not seem to be that familiar with vets. Biopsy after biopsy always came back unconclusive. If unconclusive then why worry right??

Even the removal is not a guarantee that it will come out somewhere else. They have a tendancy to spread very quickly, just keep your eye on that.

So sorry that you are watching this - it is horrible I know only too well.:sad:

[Dr Lee]

I am sorry for the stress and concern that you are having. Mast Cell Tumors can be both frustrating and scary. The grading has to do with the level of aggression and they do not necessary progress through the grades of 1,2,3.

Unfortunately grade 2 MCT can vary widely - some seem to behave more like 1 and some more like 3. The histopathology (biopsy) report sometimes can help you figure how aggressive it is in the description.

I would recommend that you have an evaluation with an oncologist.

Most vets are familiar with MCT however when they are above a grade 1, having the involvement of an oncologist may be prudent.

I hope this helps.

[BenMax]

Dr. Lee - is there any cure for this at all? Chemo was an option however due to the amount of tumours that grew it was soon decided that it would not help at that point. If the first tumour was diagnosed, do you think there would have been a chance for recovery?

Sorry to ask as for us it is too late but maybe for others this could be informative on what steps to take. In my case there were 3 vets and all the same results except the last vet was consulted when it was too late.

[SuperWanda]

Thank you Rainbow, BenMax and Dr. Lee,

The growth is just above her nose so even if the vet knew it was a MCT I am sure she 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.

I just hope that in aggravating it with the surgery that this does not make it more aggressive or somehow cause it to spread.

Our dog was not having any symptoms of allergic reaction before the operation so that is why it worries me that the surgery has now set off more problems.

We have no kids so our two dogs are our children. It will soon be the 10 year anniversary of our marriage as well as our "marriage" to her as we adopted her around the same time 10 years ago. This picture is one of my favorites of her and myself - taken just last month - we have a very special bond. It hurts to realize that they are getting older and I am finding it difficult to accept the changes in their health. I just hope that I can find it in myself to not stress and remain positive for them.

[BenMax]

Oh gosh SuperWanda - that picture is so beautifully genuine. I am PRAYING very hard for you. I really am.

I hope you get the answers you need. Try PMing Dr. Lee - you may get a quicker response to your questions.

[Dr Lee]

Originally Posted by SuperWanda

...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.

[BenMax]

Dr. Lee this is more information than what I got, so I thank you so very much.

My apologies for riding on this thread, however I was left with so many questions and not enough answers until it was too late...please forgive me SuperWanda for barging in but my heart is heavy.:sad:

[Dr Lee]

I am glad that you have asked your questions. Losing pets is always so hard. We are all here to learn and help each other.

[SuperWanda]

BenMax - I didn't feel you were barging in at all - your questions have helped me as well. I'm so sorry that you had to go through that and I appreciate the concern and advice you have given.


Dr. Lee - Thank you for the information. I just spoke with my vet and the pathology report showed that the margins are clean however there is an area on the bottom where only .1mm of tissue is clean - this is also an area with many lymphocytes. This is not thick enough to say for sure that there may not have been mast cells below that.

As for a radiation option - I have no idea if they would do that here? Don't even know if there is a canine oncologist in this city? I will ask but her opinion seemed to be to wait and watch as she said that there is a 55% chance over the next 3 years that it might return - I read in the next 6 months so might have to ask about that.

As you were saying, she also felt it was strange to see the facial swelling and hives a week later. We are to continue with benadryl and slowly ween her off of it over the next few weeks and watch for signs of swelling. She was also on the antibiotic amoxil (which she started the day of surgery) but she said that is usually well tolerated in most dogs. Since our dog has a history of a sensitive stomach that is why she prescribed it as it is fairly gentle. I guess this reaction is still a mystery - perhaps something totally unrelated but strange given it was a MCT.

I feel a better about the results but still have questions so will ask more on Thursday - that is when she will have her sutures removed.