Lipomatous lumbar mass with an attached digit and associated split cord malformation.
BACKGROUND
A male infant was born with a digit attached to a skin-covered lumbar lipomatous mass and an underlying split cord malformation.


METHODS
Surgical removal of the mass was performed at four months-of-age. By this time the digit had grown a nail and imaging and histology showed ongoing development of articulated phalanges.


RESULTS
The lipomatous mass contained a long bone, a clavicle- and scapula-like structure and a variety of other mature germ layer derivatives. These features raised a number of diagnostic considerations, including: mature teratoma, hamartoma, rudimentary parasitic twin, lipomyelomeningocele and dorsal accessory limb.


CONCLUSIONS
Based on review of the literature, the authors hypothesize that there is a pathogenetically related spectrum of skin-covered dorsal mass lesions, often associated with spinal dysraphism. These consist of a major lipomatous component and a variety of mature germ layer derivatives that can vary widely in their degree of anatomical organization from case to case.
Snelling
C M H
CM
Department of Pathology and Molecular Medicine, Queen's University and Kingston General Hospital, Kingston, Ontario, Canada.
Ellis
P M
PM
Smith
R M L
RM
Rossiter
J P
JP
D000328:Adult; D005260:Female; D006801:Humans; D008067:Lipoma / Q000150:complications* / Q000473:pathology; D008159:Lumbar Vertebrae / Q000002:abnormalities*; D008279:Magnetic Resonance Imaging / Q000379:methods; D013116:Spinal Cord / Q000002:abnormalities*; D013120:Spinal Cord Neoplasms / Q000150:complications* / Q000473:pathology