A 48-year-old woman presented to our dermatology department with a painful subcutaneous nodular lesion evolving for several years, without any other associated signs. The dermatological examination revealed a 10-mm, firm, well-limited, subcutaneous nodule adherent to the skin and located on the lateral malleolus of the right foot (Fig. 1a). Soft tissue ultrasound revealed a well-defined, oval, homogenously hypoechoic mass lesion. An excisional biopsy was performed. Macroscopically, the lesion was a firm white tumor measuring 13 mm × 10 mm × 6 mm (Fig. 1b). The histopathological study described a benign tumor proliferation consisting of smooth and spindle-shaped muscle cells arranged in bands and crossed by numerous thin-walled vascular sections with hyaline and myxoid degeneration in the central area. The histological appearance was consistent with an angioleiomyoma (Fig. 2a and 2b).

	Figure 1: a) Subcutaneous nodule on the lateral malleolus. b) Macroscopic appearance of the tumor: white nodule with specks of hemorrhage.
	Figure 2: Microscopic examination of hematoxylin and eosin-stained showed proliferation of eosinophilic smooth muscle cells with minimal nuclear pleomorphism associated with rounded or slit-like veins with muscular walls present within the tumor. a: (x10); b:(x40).

Angioleiomyoma is a rare benign tumor that develops in the muscular layer of the dermal vessels. A subcutaneous angioleiomyoma is a particular form of leiomyoma that occurs most often in young women. It presents as a solitary painful nodule of small size in the lower limbs. [1]. The pain may be spontaneous or result from exposure to cold, pressure, or emotional stress. Radiological investigations can guide the diagnosis. However, the clinical and radiological differential diagnoses of angioleiomyoma remain numerous. They include dermatofibroma, neurofibroma, smooth muscle hamartoma, schwannoma, adnexal tumors, and glomus tumors [2]. The final diagnosis of cutaneous leiomyoma is histological with hematoxylin and eosin staining sometimes supplemented by the immunohistochemical study. Cutaneous leiomyoma, and angioleiomyoma, usually occur sporadically, although some familial cases have been reported in the literature. It may be part of complex syndromes such as Gardner’s syndrome or Reed’s syndrome (multiple cutaneous and uterine leiomyomatosis) which should lead us to perform a pelvic ultrasound [3]. In addition, a few rare observations have reported an association between cutaneous leiomyomas and clear-cell renal cancers.

REFERENCES

1. Al-Jabri T, Garg S, Rao S. A rare case of angioleiomyoma of the knee:a case report. Cases J. 2009;2:7885.

2. Kumar S, Hasan R, Maddukuri SB, Mathew M. Angiomyoma presenting as a painful subcutaneous mass:a diagnostic challenge. BMJ Case Rep. 2014;2014:bcr2014206606.

3. Mejri S, Attafi Sahli S, Bouchouicha S. Multiple piloleiomyomas. Our Dermatol Online. 2017;8:509-510.