Lipoma (benign fat tumor) are usually located at the subcutaneous level (just below the skin).
It is possible, though not common, for lipoma to be located in deeper areas.
Such is the case of this patient with intramuscular lipoma, beneath or within the pectoralis minor muscle, on the right chest area. The under surface of the lipoma was adherent to the periosteum of the rib. An excision-biopsy was done.