AIRP Best Cases in Radiologic-Pathologic Correlation: Alveolar Soft-Part Sarcoma

Abstract

A 27-year-old man presented with a 1-year history of discomfort in the proximal right thigh. Six months after the onset of symptoms, he started to feel a mass in the same area, at the lateral aspect of the proximal right thigh. The mass gradually increased in size. There was no history of trauma and no associated fever, chills, or weight loss.At physical examination, there was a large palpable mass at the anterolateral aspect of the right thigh, occupying the proximal one-third of the thigh. The mass was firm and nonmovable but mildly tender. There were no overlying skin changes or associated inguinal lymphadenopathy.His earlier medical history was noncontributory. Complete blood cell count, erythrocyte sedimentation rate, and results of a basic electrolyte panel were normal.Abbreviations: ASPS = alveolar soft-part sarcoma, EMA = epithelial membrane antigen, PAS = periodic acid-Schiff, STIR = short inversion time inversion-recovery RadioGraphics 2013; 33:585-593 • Published online 10.1148/rg.332115173 • Content Codes:

Clinical presentation and CT/MRI findings of alveolar soft part sarcoma: a retrospective single-center analysis of 14 cases

“…ASPS is a clinically and morphologically distinct disease that was first defined and named by Christopherson et al. in 1952 (12,13). The 2013 World Health Organization classification of soft-tissue tumors included ASPS in the “undifferentiated soft tissue sarcoma” category (14).…”

Imaging and Pathological Features of Alveolar Soft Part Sarcoma: Analysis of 16 Patients

“…Nuclear reactivity for MyoD1 is variable. 14 In addition, most of the cases showed nuclear immunoreactivity for TFE-3 immunostain. An unbalanced translocation t (X; 17) (p11; q25), which creates the ASPSCR1–TFE3 fusion protein is classically seen in these cases.…”

“…4,6 Though conventional angiography was not done in any patient in our study, findings such as arterial feeders with prolonged staining of the tumor and late washout indicate soft tissue vascular tumor rather than an AVM. 14 Another commonly confused entity with ASPS can be hemangiomas which are benign vascular tumors. In a review by Viry et al of six children with ASPS, one case of orbital ASPS was initially suspected to be a hemangioma and embolized.…”

“…Also, angiomatous tumors like angiosarcoma, hemangiopericytoma could also have a similar imaging appearance. 14 However, these angiomatous tumors often show blood fluid levels on MRI which are not described in ASPS. 22 Retrospective study design with small sample size of 16 patients due to rare nature of this sarcoma is one of the limitations of our study.…”

Alveolar soft part sarcoma of the retroperitoneum: A case report

“…In 2002 WHO soft tissue tumor classification, Alveolar soft part sarcoma (ASPS) was included in the category of "Tumor of uncertain differentiation" [1]. ASPS is a rare but discrete soft tissue tumour accounting for 0.5-1% of softtissue sarcomas [2]. It is a slow-growing malignant neoplasm with unknown histogenesis.…”