Indian Journal of Dermatology
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Year
: 2017  |  Volume : 62  |  Issue : 1  |  Page : 108--110

Solitary subcutaneous nodule over the right elbow


Biswanath Behera1, Laxmisha Chandrashekar1, Devinder Mohan Thappa1, Nachiappa Ganesh Rajesh2,  
1 Department of Dermatology, Venereology and Leprology, JIPMER, Puducherry, India
2 Department of Pathology, JIPMER, Puducherry, India

Correspondence Address:
Dr. Nachiappa Ganesh Rajesh
Department of Pathology, JIPMER, Puducherry - 605 006
India




How to cite this article:
Behera B, Chandrashekar L, Thappa DM, Rajesh NG. Solitary subcutaneous nodule over the right elbow.Indian J Dermatol 2017;62:108-110


How to cite this URL:
Behera B, Chandrashekar L, Thappa DM, Rajesh NG. Solitary subcutaneous nodule over the right elbow. Indian J Dermatol [serial online] 2017 [cited 2021 Apr 14 ];62:108-110
Available from: https://www.e-ijd.org/text.asp?2017/62/1/108/198029


Full Text

A 25-year-old male presented with a solitary asymptomatic swelling over the right elbow of six months duration. There was no history of joint pain, breathlessness, diabetes, or any other systemic complaint. He was not on any medication. Cutaneous examination revealed solitary, non-tender, subcutaneous nodule measuring 4 mm × 4 mm over the right elbow [Figure 1]. The overlying skin was apparently normal. Other mucocutaneous, general, and systemic examinations were within normal limits. The histopathology of excised nodule revealed well-encapsulated subcutaneous tumor comprising of proliferating small-caliber blood vessels and adipose tissue [Figure 2]. The proliferating capillaries formed the bulk of the lesion and imparted an angiomatous pattern of growth with few of them containing thrombi in their lumen [Figure 3]. A variable amount of spindle cells, with few mast cells were present between the proliferating capillaries without any significant cellular atypia, pleomorphism, or mitotic figure [Figure 4].{Figure 1}{Figure 2}{Figure 3}{Figure 4}

 Question



What is your diagnosis?

 View Answer

 Answer



The diagnosis is cellular angiolipoma.

 Discussion



Cutaneous angiolipomas are the benign tumors of proliferating mature adipose tissue and capillary-sized blood vessels. They commonly occur in the subcutaneous fat of upper limbs, especially forearm of young adults and less commonly over the trunk.[1] Rarely, they can involve extradural, breast, oral, intra-articular, and bronchial sites. Familial cases have rarely been reported.[1] Clinically, they present as tender or painful nodule with erythematous or bluish surface.[1] Pain can be variable and depends upon the amount of vascularity of the lesion.[1] They are more often multiple than solitary. Multiple angiolipomas have been reported in association with diabetes mellitus, use of antiretroviral therapy (particularly with indinavir and saquinavir), and HIV infection.[1] Angiolipomas are classified into infiltrating and noninfiltrating types. Infiltrating types are more aggressive in nature and produce unusual symptoms due to infiltration of muscular, osseous, fibrocollagenous, and neural tissues and mimic malignant neoplasm.[2] Noninfiltrating types are more common and present as painful, soft, cutaneous nodules in younger individuals.[2] In our case, because of subcutaneous location and no associated pain in the nodule, the differentials we considered were rheumatoid nodule, subcutaneous granuloma annulare, solitary neurofibroma, and sarcoidosis.[1]

In contrast to other forms of lipomas including ordinary lipoma, angiolipomas are not associated with any characteristic cytogenetic abnormality, which may point towards a different pathogeneses from that of lipomas.[3]

Histology reveals well-encapsulated tumor comprising of mature adipocytes and varying proportions of irregular, anastomosing small blood vessels. The presence of luminal microthrombi and absence of cellular atypia, pleomorphism, and mitotic figures of both adipose and angiomatous components are very characteristic.[1] Cellular angiolipoma differs from angiolipoma by its predominant vascular component, which usually occupies more than 90% of the tumor area. In cellular angiolipoma, spindle cells are found to be present between the proliferating blood vessels and thought to be of pericyte origin.[4],[5] In our case, the proliferating capillaries constituted more than 90% of the tumor mass and imparted an “angiomatous growth pattern.” In case of a cellular angiolipoma, the presence of proliferating vessels with variable number of interstitial spindle cells sometimes poses diagnostic difficulty, especially while differentiating it from Kaposi's sarcoma, capillary hemangioma, spindle cell hemangioma, and spindle cell lipoma.[5]

Noninfiltrating angiolipomas can be treated by enucleation while infiltrating angiolipomas need a wide excision including normal surrounding tissue.[2] Our case demonstrates that although angiolipomas are conventionally associated with pain, they can present as a painless subcutaneous nodule and pose diagnostic difficulty in differentiating them from other benign tumors and inflammatory lesions.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Calonje E, Brenn T, Lazar A, McKee PH, editors. McKee's Pathology of the Skin with Clinical Correlations. 4th ed. Philadelphia: Elsevier; 2012.
2Lin JJ, Lin F. Two entities in angiolipoma. A study of 459 cases of lipoma with review of literature on infiltrating angiolipoma. Cancer 1974;34:720-7.
3Sciot R, Akerman M, Dal Cin P, De Wever I, Fletcher CD, Mandahl N, et al. Cytogenetic analysis of subcutaneous angiolipoma: Further evidence supporting its difference from ordinary pure lipomas: A report of the CHAMP Study Group. Am J Surg Pathol 1997;21:441-4.
4Kanik AB, Oh CH, Bhawan J. Cellular angiolipoma. Am J Dermatopathol 1995;17:312-5.
5Sheng W, Lu L, Wang J. Cellular angiolipoma: A clinicopathological and immunohistochemical study of 12 cases. Am J Dermatopathol 2013;35:220-5.