Thanks for the information. Our biggest concern with masses in this area are enlarged lymph nodes. Usually, the swelling will be right where the jaw bone and neck comes together. I am still not sure if this is exactly where the mass you have found is at or not. If it is, I would be concerned about an enlarged lymph node or salivary gland. Those would be the most likely sources of swelling in that area. Enlarged lymph nodes are usually firm and fixed, though. If this mass is soft and movable (doesn't seem to be attached to anything past the skin and underlying fat tissue), then a lymph node is less likely. A cyst, bruise, inflammatory lesion or other type of skin tumor are possible. With the size you are describing, though, a lymph node or salivary gland would be most likely. A enlarged salivary gland would feel similar to a lymph node. Both the lymph node and salivary gland can be infected. A single enlarged lymph node may be draining some type of infection, especially from the mouth. A salivary gland could form cysts in it. Of course, the worse case scenario is that it is lymphoma
(cancer of lymph nodes). Because of the location and size, I would highly recommend having your vet check this out and aspirate it to pull out cells to be evaluated under the microscope. Please let me know if you have any other questions or concerns. Hope this helps.
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