Hard to tell without an examination.
Madelung's disease (aka multiple symmetrical lipomatosis, cephalothoracic lipodystrophy, and the Launois-Bensaude syndrome) frequently appears in association with alcoholic liver disease, "low blood" count with fewer but big red blood cells and disorders of the peripheral nervous system. It has been associated with alcoholism.
FROM http://emedicine.medscape.com/article/1057855-overview :
Diffuse congenital lipomatosis
Diffuse poorly demarcated lipomas localized primarily on the trunk characterize this type (see Media File 1).
Tumors often infiltrate through muscle fibers, making them resistant to surgical removal. These tumors are composed of immature fat cells.
Benign symmetric lipomatosis (Madelung disease)
Madelung described the condition in 1888.
Lipomas of the head, neck, shoulders, and proximal upper extremities characterize this condition.
Men are affected 4 times as often as women.
The patient's history often includes excessive alcohol consumption or diabetes.
Other conditions associated with Madelung disease include malignant tumors of the upper airways, hyperuricemia, obesity, renal tubular acidosis, peripheral neuropathy, and liver disease.
Familial multiple lipomatosis
This clinical entity is characterized by few-to-many, small, well-demarcated, encapsulated lipomas that commonly involve the extremities.
Typically, this form appears during or soon after adolescence.
The neck and shoulders usually are spared (unlike benign symmetric lipomatosis).
A family history of multiple lipomas usually exists, and an autosomal dominant mode of inheritance is found.
Dercum disease (adiposis dolorosa)
Painful lipomas are the hallmark of this rare condition.
Lipomas typically occur on the extremities of obese postmenopausal women.
Alcoholism, emotional instability, and depression commonly are associated with Dercum disease.
Typically, these tender, soft, subcutaneous nodules are present in adolescence.
Tumors frequently are multilobulated and are somewhat firmer than ordinary lipomas.
The associated pain is vague and may be spontaneous or caused by pressure.
Tumors are solitary well-circumscribed nodules that typically are asymptomatic.
Usually, tumors are located in the interscapular region, axillae, neck, or mediastinum.
Histologically, hibernomas are composed of embryonic brown lipoblasts termed mulberry cells because of their appearance.
I would excise one and get a good pathologist to look at it and work you up to make sure you are otherwise in good health and do not have any of these associated disorders.