Has anyone dealt with a MCT misdiagnosis? Possibly a Spaid reaction?

Hello,

About six months ago my 5 year old Sharpei rescue had a bad, what I thought was arthritis flareup on a leg she’s had surgery on. I also noticed a lump appear around that time on her other hind leg. The vet initially thought it was a MCT but wanted the inflammation to go down before doing another in house cytology. It ended up going away so she said it was possibly an inflammatory response and to monitor it.

Fast forward to last week. I noticed another larger lump on her front left and took her in. She did the cytology and said it was for sure a MCT this time. She actually was limping a bit from an arthritis flare up at that time and then the day after I took her to the vet she had a really bad one where she was shaking, panting, wouldn’t move and seemed in a lot of pain.

I’m starting to wonder if this was actually more of a SPAID symptom now that I’ve read up on it. She’s had a few other times where she starts shaking and seems in pain before she had arthritis. Almost like a fever or bad flu and it would stop after a few hours.

I’ve read that their autoimmune systems when having this kind of reaction can cause tumors that look like mass cells. She’s on a cortical steroid but the mast is was completely gone after the first dose.

I’m trying to push for it to be sent to a lab and not in house as I want to be sure it’s cancerous before doing another surgery. She’s only 5 and has already had 4-5 surgeries.

I’m wondering if anyone else has run into this kind of experience/ advice? I mentioned SPAID to my vet (currently living abroad in Spain) and I’m not sure if it’s a language barrier or they are not aware of it, as they said from the in house cytology it’s for sure a MCT.

TLDR- has anyones Shar Pei had a lump caused by an inflammatory response that was initially misdiagnosed as a MCT? What was your experience? I don’t want to put my dog through surgery on another leg if it can be avoided as she’s already had 2 knee surgeries.