Limits...
Intramuscular spindle cell lipoma of the deltoid: a case report.

Mizoshiri N, Shirai T, Terauchi R, Arai Y, Fujiwara H, Konishi E, Tsuchiya H, Kubo T - J Med Case Rep (2015)

Bottom Line: There are several kinds of lipomas.There are only five other reported cases of intramuscular spindle cell lipoma in the literature, to our knowledge.The case of our patient is very interesting, as to date there have been few reported patients with a diagnosis of an intramuscular spindle cell lipoma in a deltoid.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, 602-8566, Japan. mizo715@koto.kpu-m.ac.jp.

ABSTRACT

Introduction: Spindle cell lipoma is an uncommon adipocytic tumor. Intramuscular lesions of this tumor are very rare. In this report, we describe a case of a patient with intramuscular spindle cell lipoma localized in a deltoid.

Case presentation: A 58-year-old Japanese man visited us because of a soft tissue mass on the lateral aspect of the left shoulder that had been noticed 2 years prior. The spherical tumor, which measured 5 cm × 4 cm, was elastic and firm on palpation and immobile. Magnetic resonance imaging revealed that the lesion was localized in the left deltoid muscle. A needle biopsy was performed to make a histological diagnosis. With a pre-operative diagnosis of intramuscular lipoma, we removed the tumor with the patient under general anesthesia. The tumor was removed with surrounding musculature and fascia. The pathological diagnosis was intramuscular spindle cell lipoma in the left deltoid muscle.

Conclusions: There are several kinds of lipomas. Spindle cell lipoma is a relatively rare variant (1.5% of all adipocytic neoplasms) that is histologically distinct and characterized by the replacement of mature fat by a mixture of mature adipocytes and undifferentiated spindle cells. There are only five other reported cases of intramuscular spindle cell lipoma in the literature, to our knowledge. The case of our patient is very interesting, as to date there have been few reported patients with a diagnosis of an intramuscular spindle cell lipoma in a deltoid.

Show MeSH

Related in: MedlinePlus

Signal intensity of the tumor on magnetic resonance imaging scans. (a) On this T1-weighted image, the tumor shows low signal intensity or isointensity to skeletal muscle at the center and high signal intensity at the periphery of the lesion. (b) On this T2-weighted image, the tumor shows high signal intensity. (c) On this gadolinium-enhanced image, the tumor shows high signal intensity.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4340779&req=5

Fig1: Signal intensity of the tumor on magnetic resonance imaging scans. (a) On this T1-weighted image, the tumor shows low signal intensity or isointensity to skeletal muscle at the center and high signal intensity at the periphery of the lesion. (b) On this T2-weighted image, the tumor shows high signal intensity. (c) On this gadolinium-enhanced image, the tumor shows high signal intensity.

Mentions: A 58-year-old Japanese man visited us because of a soft tissue mass on the lateral aspect of the left shoulder that had been noticed 2 years prior. His past and family histories were not contributory. All other laboratory examinations showed no abnormalities. The spherical tumor, measuring 5cm×4cm, was elastic and firm on palpation and immobile. There were no other findings of inflammation. Magnetic resonance imaging (MRI) revealed that the lesion was localized in the left deltoid muscle. On MRI scans, the tumor showed low signal intensity or isointensity to skeletal muscle at the center. It showed high signal intensity at the periphery of the lesion on a T1-weighted image (Figure 1a). It also showed high signal intensity on a T2-weighted image (Figure 1b) and a gadolinium-enhanced image (Figure 1c). However, the signal intensity was substantially lower than that of normal subcutaneous adipose tissue. On the basis of these radiological findings, we suspected a lipogenic tumor. A needle biopsy was performed to make a histological diagnosis. Histologically, the tumor was a lipomatous tumor consisted mostly of atypical lipocytes with a slightly greater variation in size and shape than those of normal fat. Although the atypism of the cells was slight and mitoses were not seen, a few lipoblast-like cells and fibroblast-like cells were seen. The results of MDM2 immunostaining were negative.Figure 1


Intramuscular spindle cell lipoma of the deltoid: a case report.

Mizoshiri N, Shirai T, Terauchi R, Arai Y, Fujiwara H, Konishi E, Tsuchiya H, Kubo T - J Med Case Rep (2015)

Signal intensity of the tumor on magnetic resonance imaging scans. (a) On this T1-weighted image, the tumor shows low signal intensity or isointensity to skeletal muscle at the center and high signal intensity at the periphery of the lesion. (b) On this T2-weighted image, the tumor shows high signal intensity. (c) On this gadolinium-enhanced image, the tumor shows high signal intensity.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4340779&req=5

Fig1: Signal intensity of the tumor on magnetic resonance imaging scans. (a) On this T1-weighted image, the tumor shows low signal intensity or isointensity to skeletal muscle at the center and high signal intensity at the periphery of the lesion. (b) On this T2-weighted image, the tumor shows high signal intensity. (c) On this gadolinium-enhanced image, the tumor shows high signal intensity.
Mentions: A 58-year-old Japanese man visited us because of a soft tissue mass on the lateral aspect of the left shoulder that had been noticed 2 years prior. His past and family histories were not contributory. All other laboratory examinations showed no abnormalities. The spherical tumor, measuring 5cm×4cm, was elastic and firm on palpation and immobile. There were no other findings of inflammation. Magnetic resonance imaging (MRI) revealed that the lesion was localized in the left deltoid muscle. On MRI scans, the tumor showed low signal intensity or isointensity to skeletal muscle at the center. It showed high signal intensity at the periphery of the lesion on a T1-weighted image (Figure 1a). It also showed high signal intensity on a T2-weighted image (Figure 1b) and a gadolinium-enhanced image (Figure 1c). However, the signal intensity was substantially lower than that of normal subcutaneous adipose tissue. On the basis of these radiological findings, we suspected a lipogenic tumor. A needle biopsy was performed to make a histological diagnosis. Histologically, the tumor was a lipomatous tumor consisted mostly of atypical lipocytes with a slightly greater variation in size and shape than those of normal fat. Although the atypism of the cells was slight and mitoses were not seen, a few lipoblast-like cells and fibroblast-like cells were seen. The results of MDM2 immunostaining were negative.Figure 1

Bottom Line: There are several kinds of lipomas.There are only five other reported cases of intramuscular spindle cell lipoma in the literature, to our knowledge.The case of our patient is very interesting, as to date there have been few reported patients with a diagnosis of an intramuscular spindle cell lipoma in a deltoid.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, 602-8566, Japan. mizo715@koto.kpu-m.ac.jp.

ABSTRACT

Introduction: Spindle cell lipoma is an uncommon adipocytic tumor. Intramuscular lesions of this tumor are very rare. In this report, we describe a case of a patient with intramuscular spindle cell lipoma localized in a deltoid.

Case presentation: A 58-year-old Japanese man visited us because of a soft tissue mass on the lateral aspect of the left shoulder that had been noticed 2 years prior. The spherical tumor, which measured 5 cm × 4 cm, was elastic and firm on palpation and immobile. Magnetic resonance imaging revealed that the lesion was localized in the left deltoid muscle. A needle biopsy was performed to make a histological diagnosis. With a pre-operative diagnosis of intramuscular lipoma, we removed the tumor with the patient under general anesthesia. The tumor was removed with surrounding musculature and fascia. The pathological diagnosis was intramuscular spindle cell lipoma in the left deltoid muscle.

Conclusions: There are several kinds of lipomas. Spindle cell lipoma is a relatively rare variant (1.5% of all adipocytic neoplasms) that is histologically distinct and characterized by the replacement of mature fat by a mixture of mature adipocytes and undifferentiated spindle cells. There are only five other reported cases of intramuscular spindle cell lipoma in the literature, to our knowledge. The case of our patient is very interesting, as to date there have been few reported patients with a diagnosis of an intramuscular spindle cell lipoma in a deltoid.

Show MeSH
Related in: MedlinePlus