I have lump back of neck, just below hair to the right of spine. about an inch and not painful. have seen three docs, all said don't worry.. should i?

Hard to say: If you have a soft tissue lesion anywhere that you have noticed, it bears observation. Lesions that are increasing in size, especially rapidly, or those associated with increasing pain, are concerns for malignancy. A painless mass which is constant in size, unchanging in appearance, and unchanged over time is likely benign. Lipomas are the most common soft tissue benign lesions; common and benign.