2. Case presentation
The patient, a 31-year-old male, was found several hemispheric nodules
in the skin or subcutaneous of both
buttocks, disease course of 5 years,
and these nodules were slightly soft. The patient did not feel painful
and itching in his buttocks, and the skin of buttocks was intact. The
masses of bilateral buttocks had significantly increased in the past 1
month. The case underwent mass resection and pathological examination,
and recovered well with no relapse within 5 years after surgery.
Physical examination : By palpation, we found
all masses with poor mobility,
moderate texture and no fluctuation.
Laboratory examination : Through laboratory tests, we found that
serum triglyceride was 1.62 mmol/L (normal
value 0.29-1.83mmol/L), low-density
lipoprotein was 11.2 mmol/L (normal value < 4.0mmol/L),
high-density lipoprotein was 1.51 mmol/L (normal value >
0.9 mmol/L), and cholesterol was 16.7
mmol/L (normal value 2.8-5.7 mmol/L).
Ultrasonic findings : We
found that multiple hyper echoic masses were in the skin layer of
bilateral buttocks, and the biggest mass of left buttock was about
69×14×44 millimeter in size, with clear boundary and irregular
morphology (Fig. 1). Abundant blood
flow signals were seen within the masses, and low-velocity,
low-obstruction artery and low-velocity venous blood flow spectrum were
detected (Fig. 2).
Postoperative pathological specimens : Two masses were
about
31×15×30
millimeter and 30×25×30 millimeter in
size on right buttock respectively, and a lump was about 69×14×44
millimeter in size on left buttock.
The sizes of above masses were all consistent with that measured by
ultrasound.
Pathological findings :
Histopathologic lesions of masses on
left and right buttocks were analyzed by immunohistochemical and
histochemical staining. The masses were mainly composed of a large
number of focal-like foam cells, which were nodular in distribution(Fig.
3A). Inflammatory cell infiltration, fibroblast hyperplasia with a small
amount of cholesterol deposition and hyaline degeneration were seen in
some areas(Fig. 3A).
Immunohistochemic: S-100 (-), Leu-7
(-), Desmin (-), SMA (-), inhibin (-), CD68 (+), which supported the
pathological diagnosis with xanthomas
(Fig. 3B).