This could be a number of things including a wart, an infection, a cyst, an allergic reaction, or any number of benign or malignant growths. The physical appearance can give some idea Your veterinarian will do a fine needle aspirate by using a syringe and needle to suck a sample out of the lump. The sample will be stained and examined under the microscope. This can give a basic idea of the contents of the lump. Depending on the findings, a biopsy or excision of the lump and later biopsy may be warranted.
