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The best idea is to measure the lump right now. Second, have an exam scheduled as soon as you can to have the lump examined. Many times lumps in this area can be anything from small abcesses to swollen lymph nodes and cysts. An exam will give you an idea of what the doctor thinks it is. S/he will likely recommend watching the area to note any growth and may recommend a FNA (fine needle aspirate) to determine if there is anything inside of the lump. (If one were to find pus, for example, it would indicate an abscess). After this, you will likely be directed to either a) have it removed or b) watch for growth. Having it removed and examined by a laboratory that deals with tissue samples will let you know precisely what the lump is or was caused by. If you choose to watch for growth, this is where the initial measuring will come in handy. Owners often look at a lump frequently once they realize that it's there and won't notice gradual growth or changes...therefore measuring is a more effective tool. A mass that continues to grow may be cancerous and removal will be recommended by your veterinarian.
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