Intramuscular lipoma: infiltrating vs. well-circumscribed variant
1West Virginia School of Osteopathic Medicine, Lewisburg, West Virginia, USA, 2Beckley Appalachian Regional Healthcare, Beckley, West Virginia, USA
Ivan Chernev, ARH Southern WV Clinic, 250 Stanaford Road, Beckley, WV, 25801, USA
To the editors of the Pan African Medical Journal
I read with great interest the article by Lahrach et al. named "An unusual case
of an intramuscular lipoma of the biceps brachii " published in the Pan African
Medical Journal . In this letter to the editor, I
would like to comment on intramuscularlipomas and this article in particular.
First, the authors of the article state that intramuscular lipomas are extremely
rare. I believe that although uncommon, intramuscular lipomas are not extremely
rare. The term "intramuscular lipoma"; retrieved 167 citations on PubMed.
I also believe that because lipoma is a common tumor, many cases of intramuscular
lipoma have been treated but not published in the literature. However, it is
possible that some areas are less affected than others. I recently experienced
a case of intramuscular lipoma of the thenar muscles, which seems to be a rare
Second, the authors state that a case of intramuscular lipoma involving biceps
brachii muscle could not be found in the literature. I was able to find a case
of intramuscular lipoma of the biceps brachiimuscle in a series of eight patientswith
intramuscular lipomas treated surgically and published by Su et al. [3
Third, the MRI appearance of intramuscularlipomasvaries from a small, single
and homogeneous mass identical to ordinary (superficial) lipomas, to a large,
inhomogeneous lesion with infiltrative margins. The presence of infiltrative
margins and intermingled muscle fibers in intramuscular lipomaare characteristic
and indicates a benign lesion rather than malignancy [2
single case of intramuscular lipoma with irregular margins and interdigitations
within skeletal muscle that create a typical striated appearance diagnosed with
ultrasound has been described as well [5
Fourth, I would like to make comments on couple of technical points concerning
the article published in the Pan African Medical Journal. An article by Allen et al. is cited three times in the reference section as reference number one, five and nine and article by Vandeweyer et al. is cited twice as reference number three and eight. In the discussion part the word biceps brachiallii is misspelled. Instead biceps brachii should be used.
Finally, I believe that the term intramuscular lipoma should not be interchangeably used with the term infiltrating intramuscularlipoma as not all intramuscular lipomas described in the literature showed real infiltrative qualities. Instead, I propose the following terms to be used: well-circumscribed (well-encapsulated), infiltrative and mixed (with areas of infiltration and areas which are well-circumscribed) intramuscular lipomas. Careful pathological examination of the edges of the tumor may reveal minimal infiltration to the muscle tissue in some lesions proving the infiltrative nature of the mass.
The author declares no competing interest.
- Lahrach K, el Kadi KI, Mezzani A, Marzouki A, Boutayeb
F. An unusual case of an intramuscular lipoma of the biceps brachii. Pan
Afr Med J. 2013; 15:40. PubMed | Google
- Chernev I, Tingey S. Thenar Intramuscular Lipoma: A Case Report. J Med Cases. 2013; 4(10):676-678. PubMed | Google Scholar
- Su CH, Hung JK, Chang IL. Surgical treatment of
intramuscular, infiltrating lipoma. Int Surg. 2011; 96(1):56-9. PubMed | Google
- Matsumoto K, Hukuda S, Ishizawa M, Chano T, Okabe H. MRI findings in intramuscular lipomas. Skeletal Radiol. 1999; 28(3):145-152. PubMed | Google Scholar
- Zamora MA, Zamora CA, Samayoa EA, Morales HA, Ceballos JF. High-resolution ultrasonography in an aggressive thenar intramuscular lipoma. J Ultrasound Med. 2005; 24(8):1151-5. PubMed | Google Scholar