Welcome to Justanswer! I am Dr. Altman and happy to assist you both today!
So sorry to hear that Lilly has this lump. I am happy to review a photo with the paperclip on your screen to download but I am always concerned about a hairless raised lump in the breed as they are at higher risk for mast cell tumors so I would strongly urge a veterinary exam and aspiration or "poke" with a needle to evaluate the cells and ensure it is nothing to be concerned with
This is really the only way to differentiate the concerning from the non concerning lumps definitively because a cancerous versus a noncancerous lump can appear identical on presentation
Evaluation under the microscope will be looking at the lump at a cellular level. Do the cells look normal, is it sebaceous or oil material that is benign or even fatty material indicating a lipoma or are the cells abnormal in appearance? This information is critical in order to diagnose the lump origin and whether it should be removed sooner versus later
Some tell tale signs that a lump might be more of a concern include whether it is rapidly growing, it is bothersome (scratching, licking), it is not easily picked up from the underlying tissue indicating it is attached to the muscle layer. This can be helpful but not 100 % definitive as a fine needle aspiration would be
I always advise photographing the lump with a ruler or coin next to the lump to measure the size weekly or in dark skinned dogs where it is not as readily viewable measuring with a ruler on a regular basis
Please let me know how else I can assist you both today. I am online another 15 minutes to answer additional questions
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