My dog has MCT and cardiomyopathy

[Cami]

Is the lump ON the skin? If not then a dermatologist would be a waste of time/money. A surgeon isn't the way to go either!
If you suspect it a cancerous growth then get to an oncologist otherwise find a NEW general practice vet and have them do a needle aspirate of the lump. They will check the contents and give you a recommendation.
I wouldn't automatically jump to something serious in a 2 year old. Hard to say that seeing how my girls cancer started at age two but she just had bad luck. Watch it for a week and if it changes for the worse have it looked at. If it goes away and then returns in the same place that is a bigger indicator of a MCT.
You are hyper sensitive due to all the health issues going on with your other pup (rightfully so) but take a deep breath. This may very well turn out to be nothing (praying that is the case).

 

[OscarLolamom]

Is the lump ON the skin?
The lump is under the skin, it seems to attached to rib, not very firm, but it is visible when she stands. She is not as good as patient as my Oscar. She starts jumping and making "boxer bagels" when you trying to check her thoroughly. I cross my fingers, that it is nothing. I am also thinking to ask if surgeon can check Lola's lump on Monday, as we are going to see him for Oscar.