This lump should be examined by a veterinarian. Masses can be due to insect bites, trauma, infection (abscesses), foreign bodies (cactus or grass awns), cysts, and tumors. A fine needle aspirate will be done to determine the type of growth--this is a procedure where a small needle (same size as for vaccinations) is inserted into the lump to obtain cells for examination under the microscope. Bloodwork should not be necessary unless a mass removal is planned. Radiographs (x-rays) will not be useful; they are useful to identify bony tumors.
