It's just a little lump

We are taught in school that a lump is a lump and that ALL lumps should be tested (aspirated) for signs of cancer. I will admit that sometime between 2004 and 2016, I began to stray from that important piece of information. I think we all probably do this at some point - you start to take for granted the information that an aspirate of a mass can provide. We start to say things like 'oh this feels like a fatty mass' or 'this looks like it's just a benign mass'. But truly can we say that without doing an aspirate? The honest truth...no we can't.

Recently I saw a healthy 3 year old Great Dane on which the owner had noted a small (and compared to the rest of him this was small) lump on his tail. She said it had been there for awhile, maybe a few months, and had not caused any issues and did not seem to be bothering him.  At first glance the small lump, 1 cm in diameter or less, looked harmless. There was no redness, no irritation, there wasn't even hair missing around it. And the handsome boy certainly didn't seem to care if I touched it. I could hear myself start to say "this looks pretty harmless' but then I stopped myself. Was it harmless? How did I know that?  The truth was I didn't know that and I needed to find out.

So we aspirated it and I am so glad that we did. The sample I got from this small mass contained all the answers I needed to let his owner know what we needed to do next.

See those purple cells that look like they are exploding little purple confetti everywhere? My veterinary colleagues will know exactly what those are. Mast Cells. The dreaded imposter of all cancers.

Mast cell tumors are funny - they can lurk around for a while not causing any issues. They can look like small benign growths. They trick us into thinking they are harmless until they are so big and angry we kick ourselves for not aspirating them when they are just little mast cell babies. As I applauded myself (silently of course) for aspirating the mass I knew I had to go in and tell this dog's owner that this mass was cancerous. Because of its location on his tail we couldn't just remove the mass - we had to remove almost all of his beautiful long tail. Luckily his owner did not mind and wanted to do the best thing for him. So surgery was scheduled to remove this lump and the tail it came attached to.

After surgery we submitted the mass for biopsy - we already knew it was a mast cell tumor but these tumors like to be tricky. They can be low grade or high grade, infiltrative or well circumscribed, localized or metastatic. Luckily for this young dog and his family this particular mast cell tumor was a low grade and since we removed the tail there was no chance of it recurring at that location.

We will have to monitor him for future lumps.  Trust me every single lump on this dog will be aspirated from here on out. In day to day practice, sometimes its easy to fall into shortcuts  and every now and again its good to get a reminder of why they are important.