Very worried, injection lump?!

[Rananova]

Hi everyone some advice or reassurance needed please-cant get to the vet until tomorrow!
My 13 week old kitten had her first round of injections 14 days ago.
This evening I noticed a lump between her shoulder blades in a perfect circle, the size of a large pea. I've done some googling and am worried its post vaccine sarcoma or something worse. Is this normal? I dont think its painful as she doesnt mind me inspecting it and she seems okay in herself. I've only just noticed it which is strange considering I groom her every evening.
Thanks in advance x

 

[Maurey]

Are you sure your vet vaccinated her in the scruff area? It’s been out of fashion for a while now, precisely because of sarcoma risk, even as low as it is. Cats are most typically vaccinated into the lower leg, tummy pad/primordial pouch, or tail, depending on where you live. Since you brush her daily and only just noticed it, could theoretically just be a bug bite,

If you’re sure that’s the area where she was vaccinated I wouldn’t worry, since it’s small, but keep an eye on it. If it doesn’t start further reducing in size and/or disappear in another week, I’d take her in, to be safe. Swelling post vaccination is normal, and it takes around 2 to 3 weeks to go down.

 

[FeebysOwner]

Hi! Does the lump move freely? If it does, it likely isn't vaccine related sarcoma. However, some cats do get lumps at an injection that do go away - usually no more than 6 weeks after. Nonetheless, having the vet take a look at it is still your best bet. It is possible that the vet will tell you to monitor it for a few weeks, to see if it grows or shrinks. It is my understanding that if this would be a tumor, there is at least a 75% chance it would remain local to that area rather than spreading.

 

[Rananova]

Thank you for replying! I wasn't allowed in the room with her due to their covid policy. The lump is between her shoulder blades and she hasnt been outside so dont think it could be from an insect, it's just strange I've only noticed it now! I'll call them again for an telephone app in the morning

 

[Rananova]

Hi! Does the lump move freely? If it does, it likely isn't vaccine related sarcoma. However, some cats do get lumps at an injection that do go away - usually no more than 6 weeks after. Nonetheless, having the vet take a look at it is still your best bet. It is possible that the vet will tell you to monitor it for a few weeks, to see if it grows or shrinks. It is my understanding that if this would be a tumor, there is at least a 75% chance it would remain local to that area rather than spreading.

It does move around, it feels like a big pea! When she had these vaccines she had a kitten health check and the vet described her as perfect, I've never known of any vaccine related lumps in my family cats or friends cats it's very strange and worrying x

 

[IndyJones]

Sometimes a mosquito can fly in an open door or window. Could even hitchhike on you or another household member.

A bit of localized swelling isn't unusual near an injection site. It should be noted that the injection related cancers are extremely rare relative to the number of vaccines given. Nevertheless, if it makes you feel better your vet can do a biopsy.

What you describe does sound like a mosquito bite though.

 

[kittenmittens84]

If a cat gets a subcutaneous injection sometimes fluid can stay in one spot under their skin in a harmless little “bump.” Not sure if that’s what happening with your cat, but if it is it will slowly be reabsorbed by the cat’s body and will go away.

 

[Tik cat's mum]

When I got my boy's vacation I was worried about a lump on his shoulder. My vet injected the back of the neck. So when I took him for his second shot I asked the vet to check it. It turned out to be his micro chip, it did swell up to about the size of a large pea you can still feel it now a very small pea. But he's perfectly fine and healthy, if you are concerned just ask the vet when you go for next jab. The vet scaned his chip to show me it was that, it only gave a beep directly over his bump. Thought I'd mention in case like me you got your kitten microchiped around the same time as vacations.