Alveolar soft part sarcoma is an unusual tumor with highly characteristic histopathology and ultrastructure, controversial histogenesis, and enigmatic clinical behavior (Lieberman et al., 1989; Ordonez, 1999). The typical histology of ASPS shows well-defined nests of cells with abundant ... Alveolar soft part sarcoma is an unusual tumor with highly characteristic histopathology and ultrastructure, controversial histogenesis, and enigmatic clinical behavior (Lieberman et al., 1989; Ordonez, 1999). The typical histology of ASPS shows well-defined nests of cells with abundant pink cytoplasm. The loss of central cohesion produces a pseudoalveolar appearance (Ladanyi et al., 2001).
Most cases of ASPS occur in the second and third decade of life, with a slight female predilection (Ordonez, 1999). ASPS usually involves the muscle and deep soft tissues of the extremities, but has also been reported in ... Most cases of ASPS occur in the second and third decade of life, with a slight female predilection (Ordonez, 1999). ASPS usually involves the muscle and deep soft tissues of the extremities, but has also been reported in tissues where skeletal muscle is absent. Ultrastructural analysis shows secretory-like granules and, in about half of cases, characteristic rectangular or rhomboid crystalline cytoplasmic deposits of unknown composition (Ordonez, 1999). Distant metastases are common but often indolent. Although prolonged survival is possible even in patients with metastases, the long-term disease-specific mortality is high (Lieberman et al., 1989).
Ladanyi et al. (2001) detected an ASPSCR1/TFE3 fusion transcript in all 12 ASPS cases studied. The ASPSCR1/TFE3 fusion replaces the N-terminal portion of TFE3 by the fused ASPSCR1 sequences, while retaining the TFE3 DNA-binding domain, implicating transcriptional deregulation ... Ladanyi et al. (2001) detected an ASPSCR1/TFE3 fusion transcript in all 12 ASPS cases studied. The ASPSCR1/TFE3 fusion replaces the N-terminal portion of TFE3 by the fused ASPSCR1 sequences, while retaining the TFE3 DNA-binding domain, implicating transcriptional deregulation in the pathogenesis of ASPS.