Lipoma Sternum What Do You Think This Is -- Cancer, Lipoma, Or A Cyst?

What do you think this is -- Cancer, Lipoma, or a Cyst? - lipoma sternum

I am 15 years months and two I have found irregular, soft lumps under my sternum. I drew him for a while and I tried to figure out what it was, and asked the doctor when I saw him a month later. It may or may not be increased this month. He said it could be a swollen costochondral and leave him alone for a month. The following month (today), I saw the doctor and changed the diagnosis of a cyst - possibly lipoma. He does not believe that it is cancer, and he said if I just saw longer. However, since nothing grows, was completely painless and does not seem to dramatically change during the last few months, do you think could be a cyst, lipoma, or cancer? It seemed a slightly higher area under the breastbone, and a little aside for a moment, and I think he has grown considerably during the first month or so notice and put me in, but not every month. If the cancer was not growing fast, and then simply disappear, right? There is no visible swelling, no pain or discomfort. A package washere for a few months, and not at all changed in a month. Well, what do you think? I do not have a biopsy, which is costly, painful and leaves a scar ...

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