Cat has lump after vaccines

[Countrygirl18]

A week ago we took Ninja for a general health check and to get vaccines. She got rabies 3 year, distemper, and a steroid injection for allergies and hair loss on her back legs.

She is perky, playful, hungry and her usual self. Also the steroid is working and she’s growing hair back. But tonight I noticed a soft lump like between her shoulder blades under her skin. Didn’t bother her when I touched it. Like half the size of one of those colorful bouncy balls.
It definitely was not there before the appointment and besides the allergies she checked out in great health. Anything to worry about?

[Alex_and_Bodie_s_Mom]

Could be an abscess - I’ve had cats get them after an injection. It’s rare, but it does happen.

Odd that it doesn’t bother her in that case - maybe the steroids?

If it gets bigger in the next few days, take her to the vet.

[CindyCRNA]

Vet type folks here, that’s too soon for a fibrosarcoma, correct?

[OzarksRider]

It’s not necessarily something to worry about but keep an eye on it. Several of my cats have had lumps after vaccinations that gradually resolved over several weeks. But, vaccines can cause sarcomas in cats, so if the lump doesn’t go away after about a month let the vet take a look at it. Or if the lump is growing take the cat in to the vet right away.

[phantomhorse]

@CindyCRNA

Vet type folks here, that’s too soon for a fibrosarcoma, correct?

While of course you can never say never, that certainly would be very fast.

In addition, most clinics give vaccines to cats in very specific locations - rabies is normally administered in the right hind leg and FVRCP in the right front leg. That means the lump is probably where the steroids were injected.