Microchip caused a growth/tumor

bee9212

TCS Member
Thread starter
Young Cat
Joined
May 3, 2015
Messages
45
Reaction score
13
Hi friends,

As the title states, my cats microchip is now encapsulated by hard tissue and is scheduled to be removed this week! A little backstory: my cat is 9 years old and was microchipped before he turned 1 by his rescue. Over the years his microchip has migrated from in between his shoulders to now in his left armpit. It's been there for a few years but in January we noticed it felt a little ''lumpy'' and took him in to be seen. The vet verified that his microchip was still there and told us to keep an eye on it. Within the next 3 weeks it went from ''lumpy'' to a hard mass completely engulfing the microchip. He is scheduled to have it removed this week. Anyone else ever heard of this happening? My vet has never seen nor heard of this and is pretty confident it's just the chip causing an issue but we plan on sending it for a pathology report just to be safe. She also mentioned its too far back to be his lymph node but will check the nodes in the area while he's sedated. So strange!!
 

Mr. Meow

Special needs cat expert.
Alpha Cat
Joined
Dec 25, 2020
Messages
479
Reaction score
1,189
Location
Ohio
Hi friends,

As the title states, my cats microchip is now encapsulated by hard tissue and is scheduled to be removed this week! A little backstory: my cat is 9 years old and was microchipped before he turned 1 by his rescue. Over the years his microchip has migrated from in between his shoulders to now in his left armpit. It's been there for a few years but in January we noticed it felt a little ''lumpy'' and took him in to be seen. The vet verified that his microchip was still there and told us to keep an eye on it. Within the next 3 weeks it went from ''lumpy'' to a hard mass completely engulfing the microchip. He is scheduled to have it removed this week. Anyone else ever heard of this happening? My vet has never seen nor heard of this and is pretty confident it's just the chip causing an issue but we plan on sending it for a pathology report just to be safe. She also mentioned its too far back to be his lymph node but will check the nodes in the area while he's sedated. So strange!!
In the tens of thousands of animals I've encountered over my years with a local SPCA, I've never heard of this issue before. It seems like a fluke, however, every animal is different and there is always the possibility that his body reacted negatively to the microchip, even all these years later. It's also possible that the microchip is/was/became defective or damaged over the years, causing his body to react to it.
I agree you're doing the right thing by having it dealt with, along with sending it out for the pathology report. Please keep us posted on the results, because I'm very interested in seeing what they show. I hope everything goes well!
 

Mamanyt1953

Rules my home with an iron paw
Staff Member
Forum Helper
Joined
Oct 16, 2015
Messages
24,727
Reaction score
40,745
Location
Havelock, North Carolina
This is absolutely a first for me, as well. I've certainly seen/heard of them migrating before, but never becoming incapsulated. I did a pretty intensive Google search, and could not find it even mentioned as a possibility. And yes, please do let us know the results!
 

Antonio65

TCS Member
Top Cat
Joined
Feb 27, 2017
Messages
3,902
Reaction score
216
Location
Orbassano - Italy
Though I can't 100% sure and obviously I couldn't fine any source for this bit of info, I once heard of something like this, or at least I heard about the suspect that microchips could cause a skin tissue reaction to the point of causing a tumor, even if this is a very remote chance.
Please, let us know what the vet will find.
 

gilmargl

TCS Member
Super Cat
Joined
Feb 12, 2013
Messages
808
Reaction score
1,324
Location
Germany, NRW
I did some google searches (English and German Internet souces). The following text is informative and appears to be reliable. Further information on the source can be seen in the link I've included at the end of the quote.

"What Do the Studies Show?
According to the American Veterinary Medical Association:
  • The British Small Animal Veterinary Association (BSAVA) maintains a database of adverse reactions to microchips. Since the database was started in 1996, over 4 million animals have been microchipped and only 391 adverse reactions have been reported. Of these reactions, migration of the microchip from its original implantation site had the highest numbers reported while tumor formation had much lower numbers.
  • There have been some old reports of mice and rats developing cancer with implanted microchips. However, the majority of them were being used for cancer studies when the tumors were found, and the rat and mice strains used in the studies were known to be more likely to develop cancer.
  • Tumors associated with microchips in two dogs and two cats have been reported, but in at least one dog and one cat, the tumor could not be directly linked to the microchip itself, and it is possible that it was caused by something else."
Source of Information

I hope the operation goes well. Good luck B bee9212 !
 
  • Thread Starter Thread Starter
  • #6

bee9212

TCS Member
Thread starter
Young Cat
Joined
May 3, 2015
Messages
45
Reaction score
13
Thank you all for your kind wishes for my kitty! He came home yesterday from his surgery and is doing well. The vet said it was all fibrous scar tissue encapsulating the microchip and 100% looked like just a reaction to the chip itself.

has anyone been given Metacam for their kitties post-surgery recovery? I am so hesitant to give it to him after reading up on possible side effects to their kidneys. My vet said only to give it if he needs it and so far he’s eating and using the litter box fine but he is a little reserved still and “quiet.” I appreciate any feedback you have for us!
 

Attachments

Antonio65

TCS Member
Top Cat
Joined
Feb 27, 2017
Messages
3,902
Reaction score
216
Location
Orbassano - Italy
Glad to read it was much better than expected! Great news!

I had to give some drops of Metacam for some days to my cat due to a severe situation, and my cat was already suffering from kidney disease. In her case it was absolutely necessary, but if your cat is fine, eating, using the litter box and all, just give him some time and everything will be alright even without the med.

P.S.: He's a very handsome guy! :)
 

gilmargl

TCS Member
Super Cat
Joined
Feb 12, 2013
Messages
808
Reaction score
1,324
Location
Germany, NRW
I'm glad everything went well! I've also used Metacam as painkiller on the day after surgery (dental work, spaying and other ops). Like most medication, it should not be used longer than necessary, but the benefits outweigh "possible" side effects. When Katy had 4 cysts removed she hardly required painkillers, one day was long enough. But when she had teeth extracted I was very glad to have Metacam to help her eat for at least 10 days after the operation. Your kitty will be a bit quiet for a few days but if he's eating he probably won't need painkillers after the second day following his operation.
 
Top