Cystic and calcified PEComa of the ligamentum teres
PEComas are tumors derived from epithelioid perivascular cells that typically coexpress smooth muscle and melanocytic markers. The family of PEComas includes angiomyolipoma, clear cell “sugar” tumor, and lymphangioleiomyomatosis. Some of these tumors may be associated with tuberous sclerosis complex. PEComas of the ligamentum teres (also called in this location “clear cell myomelanocytic tumors”) are rare, but the ligamentum teres location is the most classic in children. Thirteen cases have been reported in the literature, within or in the immediate vicinity of falciform ligament/ligamentum teres.1-3 There was a marked female predominance with a mean age of 20 years (range, 3-54 years), a mean size of 8 cm (range, 5-20 cm), and a significant risk of metastasis (3 of 13 cases). Many of the lesions were calcified and had hemorrhagic and cystic alterations.
In the absence of established malignancy criteria, PEComas must be considered to have an uncertain malignant potential, requiring surgical resection and long-term monitoring. A mass of the ligamentum teres should always lead to consideration of the diagnosis of PEComa, even in adults, and even with cystic presentation. Moreover, most frequently, other tumors of the ligamentum teres are malignant (local extension of hepatocellular carcinoma, metastatic adenocarcinoma of gastrointestinal or gynecological origin). The patient was free of disease at 6 months’ follow-up.
1. Folpe AL, Goodman ZD, Ishak KG, et al. Clear cell myomelanocytic tumor of the falciform ligament/ligamentum teres: a novel member of the perivascular epithelioid clear cell family of tumors with a predilection for children and young adults. Am J Surg Pathol. 2000;24:1239-46.
2. Folpe AL, Mentzel T, Lehr HA, et al. Perivascular epithelioid cell neoplasms of soft tissue and gynecologic origin. Am J Surg Pathol. 2005;29:1558-75.
3. Alaggio R, Cecchetto G, Martignoni G, et al. Malignant perivascular epithelioid cell tumor in children: description of a case and review of literature. J Pediatr Surg. 2012;47:31-40.