Soft tissue sarcomas with non-EWS translocations: molecular genetic features and pathologic and clinical correlations

Abstract

Many soft tissue sarcoma subtypes have consistent chromosomal translocations with novel fusion genes, which result in disordered cellular function. The microscopic appearances, immunophenotype and behaviour of such tumours relate to the genetic events to a variable extent. This paper reviews the molecular pathology and related morphological and clinical features of sarcomas with non-EWS translocations. These include synovial sarcoma, alveolar rhabdomyosarcoma, alveolar soft part sarcoma, dermatofibrosarcoma protuberans, low-grade fibromyxoid sarcoma, infantile fibrosarcoma and inflammatory myofibroblastic tumour.

Molecular diagnosis of dermatofibrosarcoma protuberans: A comparison between reverse transcriptase‐polymerase chain reaction and fluorescence in situ hybridization methodologies

“…Therefore, FISH and RT-PCR showed a similar specificity (100%), but FISH was more sensitive than RT-PCR (91% vs. 72%; P ¼ 0.003). Sensitivity, specificity, positive predictive and NPVs for each of the two testing methods are summarized in Tables 2 and 3 (Fisher, 2010). In some instances, these techniques can also help to identify cases suitable for specific therapies (Jain et al, 2010).…”

Metastatic Monophasic Synovial Sarcoma: A challenging Diagnosis on Fine Needle Aspiration with Broad Differential Diagnosis

“…In either type of synovial sarcomas, epithelial markers, such as EMA and cytokeratin, may be reactive, however the golden diagnostic tool in about 90% of cases is the t(X;18) (p11;q11) translocation [12]. This is a rearrangement of the SS18 gene (formerly known as SYT) in the 18q11 region and one of the SSX1, SSX2, or SSX4 genes in Xp11 [13]. Currently, surgical excision is the main treatment modality for SS.…”

“…Currently, surgical excision is the main treatment modality for SS. Radiotherapy decreases the rate of local recurrence and adjuvant chemotherapy shown to increase time to local or distal recurrence, but not necessarily improve overall survival [13]. Spillane et al [14], studied 150 cases of synovial sarcoma which showed a 5 year survival rate of 57%.…”

Curent Concepts in Pathology of Soft Tissue Sarcoma

“…Despite its name, it is neither related to nor does it arise from synovial cells. Microscopically, biphasic, monophasic spindle cell, poorly differentiated, calcifying/ossifying and myxoid subtypes have been described [13]. Immunohistochemistry is particularly useful in the diagnosis of the monophasic spindle cell variant, which is more difficult to distinguish from other spindle cell sarcomas on morphologic grounds alone.…”

“…Sarcomas with non-EWS translocations are spindle, polygonal or small round cell tumours with varying behaviour, which mostly occur in children or young adults. They include synovial sarcoma, alveolar rhabdomyosarcoma, alveolar soft part sarcoma, dermatofibrosarcoma protuberans, low-grade fibromyxoid sarcoma, infantile fibrosarcoma and inflammatory myofibroblastic tumour [13].…”