Lump on arm, should I be concerned?

Dear Ask The Doctor: Hi i have a pes size lump which is hard on my upper outer left arm which as been there for over a month but which could be longer but onley noticed it then it does not bother me in anyway should i be concernd about this and get it checked out i feel such a fool going to see my gp with such a small problem hense asking u thanks

Dear Jackie: Most lumps in the arms are lipomas or sebaceous cysts that do not require any treatment other than observation. The only time a lump may cause a concern is if it is tender, is growing is size or if there is a discharge from the lump.