Lipomatosis is a condition where there is diffuse excessive fat deposition within the body. Although considered a single entity in the WHO classification of soft tissue and bone tumors 7, lipomatosis encompasses a variety of conditions heterogeneous in demographics, distribution and etiology. These are, therefore, discussed separately (see below).
On this page:
Terminology
Importantly many of the conditions that have an abnormal accumulation of fat in certain regions (lipomatosis) can also have a simultaneous loss of fat in other regions (lipodystrophy); HIV-associated lipodystrophy is a good example.
Lipomatosis conditions
-
neck and upper region of the trunk
-
heart
-
abdomen and pelvis
abdomen: diffuse intraabdominal lipomatosis
retroperitoneum: retroperitoneal lipomatosis 1-2
pelvis: pelvic lipomatosis
pancreas: pancreatic lipomatosis
ileocecal valve: lipomatosis of the ileocecal valve
colon: colonic lipomatosis 6
-
renal:
epidural space: epidural lipomatosis
Associations conditions
Pathology
Lipomatosis, regardless of cause, is characterized histologically by mature adipocytes arranged in lobules and sheets 7.
Treatment and prognosis
In many instances, no treatment is required, or the underlying cause can be treated (e.g. Cushing syndrome). When pronounced or of cosmetic concern, surgical removal can be performed although recurrence is common 7.
Occasionally, if extensive, the accumulation of fat can cause mechanical compression and result in regional symptoms which will depend on the location (e.g. nerve root/cauda equina compression or laryngeal compression).
Differential diagnosis
Possible imaging differential considerations include:
lipoma: "distinct" fat-containing lesion
low grade diffuse fat series tumor