I noticed a <1 cm subcutaneous painless lump in the left infraclavicular area (under collar bone) a little over a month ago. It feels somewhat soft and moves about freely. Twice in the last week I've awakened in the middle of the night with minimal sweating (not to the extent you explain as being worrisome). No other classic symptoms of lymphoma. In fact, I've gained 10 to 15 pounds in the last six months with strenuous exercise. My PCP says it's consistent with a lipoma due to its non-fixed nature and texture. He doesn't seem to be concerned. Could you please explain the difference between what a swollen node feels like versus a lipoma. Hope you can ease my mind. Thanks for your time.

A lipoma is a growth which is composed of fatty tissue. Lipomas can appear on most parts of the body and are very common. Although it is indeed true that many providers can feel a lipoma, which tends to feel rubbery, and can make the diagnosis of lipoma, there is no way to be 100% sure without a biopsy. Lymph nodes harboring lymphoma tend to be firmer. Since you are not have systemic symptoms (fevers, chills, night sweats) and since you didn't indicate that the mass is growing, it is reasonable to see what happens to it over the course of a few months. HOWEVER, if you feel unconfortable with this "watch and see" approach, it is equally reasonable to have it biopsied.