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The clinical relevance of accurately diagnosing pleomorphic sarcomas has been shown, especially in cases of undifferentiated pleomorphic sarcomas with myogenic differentiation, which appear significantly more aggressive. To establish a new smooth muscle differentiation classification and to test its prognostic value, 412 sarcomas with complex genetics were examined by immunohistochemistry using four smooth muscle markers (calponin, h-caldesmon, transgelin and smooth muscle actin). Two tumor categories were first defined: tumors with positivity for all four markers and tumors with no or incomplete phenotypes. Multivariate analysis demonstrated that this classification method exhibited the strongest prognostic value compared with other prognostic factors, including histological classification. Secondly, incomplete or absent smooth muscle phenotype tumor group was then divided into subgroups by summing for each tumor the labeling intensities of all four markers for each tumors. A subgroup of tumors with an incomplete but strong smooth muscle differentiation phenotype presenting an intermediate metastatic risk was thus identified. Collectively, our results show that the smooth muscle differentiation classification method may be a useful diagnostic tool as well as a relevant prognostic tool for undifferentiated pleomorphic sarcomas.

Alterations of the p53 pathway are among the most frequent aberrations observed in human cancers. We have performed an exhaustive analysis of TP53, p14, p15, and p16 status in a large series of 143 soft tissue sarcomas, rare tumors accounting for around 1% of all adult cancers, with complex genetics. For this purpose, we performed genomic studies, combining sequencing, copy number assessment, and expression analyses. TP53 mutations and deletions are more frequent in leiomyosarcomas than in undifferentiated pleomorphic sarcomas. Moreover, 50% of leiomyosarcomas present TP53 biallelic inactivation, whereas most undifferentiated pleomorphic sarcomas retain one wild-type TP53 allele (87.2%). The spectrum of mutations between these two groups of sarcomas is different, particularly with a higher rate of complex mutations in undifferentiated pleomorphic sarcomas. Most tumors without TP53 alteration exhibit a deletion of p14 and/or lack of mRNA expression, suggesting that p14 loss could be an alternative genotype for direct TP53 inactivation. Nevertheless, the fact that even in tumors altered for TP53, we could not detect p14 protein suggests that other p14 functions, independent of p53, could be implicated in sarcoma oncogenesis. In addition, both p15 and p16 are frequently codeleted or transcriptionally co-inhibited with p14, essentially in tumors with two wild-type TP53 alleles. Conversely, in TP53-altered tumors, p15 and p16 are well expressed, a feature not incompatible with an oncogenic process.

Intimal sarcoma (IS) is a rare, malignant, and aggressive tumor that shows a relentless course with a concomitant low survival rate and for which no effective treatment is available. In this study, 21 cases of large arterial blood vessel IS were analyzed by immunohistochemistry and fluorescence in situ hybridization and selectively by karyotyping, array comparative genomic hybridization, sequencing, phospho-kinase antibody arrays, and Western immunoblotting in search for novel diagnostic markers and potential molecular therapeutic targets. Ex vivo immunoassays were applied to test the sensitivity of IS primary tumor cells to the receptor tyrosine kinase (RTK) inhibitors imatinib and dasatinib. We showed that amplification of platelet-derived growth factor receptor α (PDGFRA) is a common finding in IS, which should be considered as a molecular hallmark of this entity. This amplification is consistently associated with PDGFRA activation. Furthermore, the tumors reveal persistent activation of the epidermal growth factor receptor (EGFR), concurrent to PDGFRA activation. Activated PDGFRA and EGFR frequently coexist with amplification and overexpression of the MDM2 oncogene. Ex vivo immunoassays on primary IS cells from one case showed the potency of dasatinib to inhibit PDGFRA and downstream signaling pathways. Our findings provide a rationale for investigating therapies that target PDGFRA, EGFR, or MDM2 in IS. Given the clonal heterogeneity of this tumor type and the potential cross-talk between the PDGFRA and EGFR signaling pathways, targeting multiple RTKs and aberrant downstream effectors might be required to improve the therapeutic outcome for patients with this disease., (©2010 AACR.)

Sarcomas are heterogeneous and aggressive mesenchymal tumors. Histological grading has so far been the best predictor for metastasis-free survival, but it has several limitations, such as moderate reproducibility and poor prognostic value for some histological types. To improve patient grading, we performed genomic and expression profiling in a training set of 183 sarcomas and established a prognostic gene expression signature, complexity index in sarcomas (CINSARC), composed of 67 genes related to mitosis and chromosome management. In a multivariate analysis, CINSARC predicts metastasis outcome in the training set and in an independent 127 sarcomas validation set. It is superior to the Fédération Francaise des Centres de Lutte Contre le Cancer grading system in determining metastatic outcome for sarcoma patients. Furthermore, it also predicts outcome for gastrointestinal stromal tumors (GISTs), breast carcinomas and lymphomas. Application of the signature will permit more selective use of adjuvant therapies for people with sarcomas, leading to decreased iatrogenic morbidity and improved outcomes for such individuals.

Soft tissue sarcomas (STS) with complex genomic profiles (50% of all STS) are predominantly composed of spindle cell/pleomorphic sarcomas, including leiomyosarcoma, myxofibrosarcoma, pleomorphic liposarcoma, pleomorphic rhabdomyosarcoma, malignant peripheral nerve sheath tumor, angiosarcoma, extraskeletal osteosarcoma, and spindle cell/pleomorphic unclassified sarcoma (previously called spindle cell/pleomorphic malignant fibrous histiocytoma). These neoplasms show, characteristically, gains and losses of numerous chromosomes or chromosome regions, as well as amplifications. Many of them share recurrent aberrations (e.g., gain of 5p13-p15) that seem to play a significant role in tumor progression and/or metastatic dissemination. In this paper, we review the cytogenetic, molecular genetic, and clinicopathologic characteristics of the most common STS displaying complex genomic profiles. Features of diagnostic or prognostic relevance will be discussed when needed.

Aim: The specific natural history of superficial soft tissue sarcomas (S-STS) has been rarely considered. We describe the clinical characteristics of a large series of S-STS (N=367) from the French Sarcoma Group (GSF-GETO) database and analyse the prognostic factors affecting outcome., Methods: We performed univariate and multivariate analyses for overall survival (OS), metastasis-free survival (MFS) and local recurrence-free survival (LRFS)., Results: The median age was 59 years. Fifty-eight percent patients were female. Tumour locations were as follows: extremities, 55%; trunk wall, 35.4%; head and neck, 8% and unknown, 1.6%. Median tumour size was 3.0 cm. The most frequent tumour types were unclassified sarcoma (24.3%) and leiomyosarcoma (22.3%). Thirty-three percent of cases were grade 3. Median follow-up was 6.18 years. The 5-year OS, MFS and LRFS rates were 80.9%, 80.7% and 74.7%, respectively. Multivariate analysis retained histological type and wide resection for predicting LRFS and histological type and grade as prognostic factors of MFS. The factors influencing OS were age, histological type, grade and wide resection. STS with early invasion into but not through the underlying fascia had a significantly poorer MFS than with strict S-STS., Conclusion: S-STS represent a separate category characterised by a better outcome. Adequate surgery, i.e. wide resection, is essential in the management of S-STS.

Epithelioid sarcoma (ES) is rare with a poor prognosis and for which a loss of INI1 expression has been recently reported. We report a study of 106 cases with clinical, histologic, and immunohistochemical data, including INI1 expression, and follow-up data. Of the 106 cases, 70 were the conventional subtype and 36 the large cell subtype. INI1 was negative in 86 cases (81.1%): 57 (81%) of 70 conventional and 29 (81%) of 36 large cell subtypes. Treatment modalities were available for 76 and follow-up for 80 patients. Of the 80 patients, 43 (54%) experienced metastasis and 25 (31%) died of the disease. Univariate analysis indicated that tumor size and mitotic index were significant for metastasis-free survival, whereas proximal location, tumor size, tumor multifocality, and mitotic index were significant for overall survival. Loss of expression of INI1 is frequent in the conventional and large cell subtypes of ES and can be used as a diagnostic marker, but it has no prognostic impact.

During the last 10 years, molecular testing of soft tissue tumors has become increasingly important, not only in the diagnostic approach of these lesions, but also regarding their prognosis and pathogenesis. A subset of soft tissue sarcomas bear chromosomal abnormalities including reciprocal translocations, deletions, mutations and amplifications, which turned out to be histotype specific. Beside their diagnostic value in sarcoma typing and subtyping (always in an appropriate clinical and histologic context), some of these abnormalities may also impact on treatment response and/or on prognosis. The aim of this review is to provide an overview of the most informative soft tissue sarcoma chromosomal abnormalities, and to give some clues about why and how we should detect them. Some sarcoma types (Ewing sarcoma, rhabdomyosarcomas, synovial sarcoma, well-differentiated/dedifferentiated and myxoid liposarcomas, gastrointestinal stromal tumors--GIST, malignant rhabdoid tumor) will be studied in more detail and the potential implication of these abnormalities in tumor genesis, growth, and maintenance will be briefly discussed.

MDM2 and CDK4 immunostaining can be useful adjuncts in diagnosing liposarcoma among soft tissue neoplasms. We examined the reproducibility of MDM2 and CDK4 staining between 2 laboratories and between tissue microarrays and whole tissue sections. Sixty-two soft tissue tumors were immunostained at the Bergonié Institute, Bordeaux, France, and the Curie Institute, Paris, France. We also examined 203 soft tissue neoplasms on standard tissue sections and tissue microarrays. There was high concordance of results obtained from the 2 laboratories (with 2 different pathologists) for MDM2 (kappa, 0.93) and CDK4 (kappa, 0.8) staining. There also was excellent concordance between results on tissue microarray and on whole tissue sections for MDM2 (kappa, 0.80) and CDK4 (kappa, 0.93). Immunostaining for MDM2 and CDK4 is a reproducible technique that may be exported to different laboratories for routine use. Tissue microarray is indicated for studying large series.

In a previous study, we showed that telomerase activity (TA) and human telomerase reverse transcriptase (hTERT) mRNA expression were undetectable in benign mesenchymal lesions and low-grade soft tissue sarcomas (STSs), but detectable in about 50% of intermediate-/high-grade STSs. We wondered if this lack of TA or hTERT mRNA expression could be related to the tumor sample examined and if there was a relationship between the former 2 parameters and telomere length. Two separate tumor samples from 37 STSs were examined for telomerase activity, using the telomerase repeat amplification protocol (TRAP) assay and for hTERT mRNA expression, using RT-PCR. Telomere length was determined in each tumor sample, using the terminal restriction fragments (TRF) technique. Significant variations in telomere length, TA and hTERT mRNA expression between 2 samples of the same tumor were observed in 27%, 11% and 27% of STSs, respectively. Telomere length did not correlate with TA or hTERT mRNA expression. Despite great intratumoral heterogeneity in telomere length, short and long telomeres were more often seen in the low/intermediate-grade and high-grade STS categories, respectively. Few STSs that showed a TRF pattern suggestive of alternative lengthening of telomeres (ALT) may contain ALT subpopulations., (Copyright 2002 Wiley-Liss, Inc.)

The aim of the present study is to assess the disease profile, outcome and prognostic factors in patients treated with surgery combined with radiotherapy (RT), with or without chemotherapy (CXT), for soft-tissue sarcoma (STS) in a multidisciplinary setting. One hundred and sixty-four patients with STS treated between 1980 and 2010 at the Centre Hospitalier Universitaire Vaudois were enrolled in this retrospective study. Seventy-six percent of patients underwent postoperative RT with (24%), or without (52%) CXT, 15% preoperative RT with (5%), or without (10%) CXT, surgery alone (7%), or RT alone (2%) with or without CXT. The median follow-up was 60 months (range 6-292). Local failure was observed in 18%, and distant failure in 21% of the patients. Overall survival (OS), diseasefree survival (DFS), local control (LC) and distant metastases-free survival (DMFS) were 88%, 68%, 83%, and 79% at 5 years, and 80%, 56%, 76%, and 69% at 10 years, respectively. In univariate analyses, favorable prognostic factors for OS, DFS, and DMFS were tumor size 6 cm or less, World Health Organization (WHO)/Zubrod score 0, and stage 2 or less. Age and superficial tumors were favorable only for OS and DMFS respectively. STS involving the extremities had a better outcome regarding DFS and LC. Histological grade 2 or less was favorable for DFS, DMFS, and LC. Radical surgery was associated with better LC and DMFS. RT dose more than 60 Gy was favorable for OS, DFS, and LC. In multivariate analyses, independent factors were age for OS; tumor size for OS, DFS and DMFS; WHO/Zubrod score for OS, DFS and LC; hemoglobin level for DFS; site for DFS and LC; tumor depth for DMFS; histological grade for DFS and LC; surgical procedure for LC and DMFS; and RT dose for OS. This study confirms that in a multidisciplinary setting, STS have a fairly good prognosis. A number of prognostic and predictive factors, including the role of surgery combined with RT, were identified. Regarding RT, a dose of more than 60 Gy was associated with a better outcome, at the price of a higher toxicity. We could not demonstrate a superiority of preoperative RT over postoperative RT. [ABSTRACT FROM AUTHOR]

Abstract: Pleomorphic soft tissue sarcomas (STS) in adults comprise a wide range of neoplasms which can be separated into two categories: those showing myogenic differentiation (e.g. pleomorphic leiomyosarcoma and pleomorphic rhabdomyosarcoma) and those lacking this feature (e.g. myxofibrosarcoma and extraskeletal osteosarcoma). Most are high-grade, aggressive STS, although a subset belongs to the low-grade category (e.g. myxoinflammatory fibroblastic sarcoma and pleomorphic hyalinizing angiectatic tumour). Except for dedifferentiated liposarcomas, myogenic differentiation in pleomorphic sarcomas is an adverse prognostic factor, being associated with more aggressive behaviour and higher metastatic rate. Histological subtype, large size, high tumour grade, deep situation, vascular invasion, location outside the limbs and previous history of tumour recurrence(s) are additional negative prognostic indicators. This review will focus on the salient pathological, molecular and prognostic characteristics of the most common myogenic and non-myogenic pleomorphic STS. [Copyright &y& Elsevier]

Cancer stem cells (CSCs) display plasticity and self-renewal properties reminiscent of normal tissue stem cells, but the events responsible for their emergence remain obscure. We recently identified CSCs in Ewing sarcoma family tumors (ESFTs) and showed that they retain mesenchymal stem cell (MSC) plasticity. In the present study, we addressed the mechanisms that underlie ESFT CSC development. We show that the EWS-FLI-1 fusion gene, associated with 85%·90% of ESFTs and believed to initiate their pathogenesis, induces expression of the embryonic stem cell (ESC) genes OCT4, SOX2, and NANOG in human pediatric MSCs (hpMSCs) but not in their adult counterparts. Moreover, under appropriate culture conditions, hpMSCs expressing EWS-FLI-1 generate a cell subpopulation displaying ESFT CSC features in vitro. We further demonstrate that induction of the ESFT CSC phenotype is the result of the combined effect of EWS-FLI-1 on its target gene expression and repression of microRNA-145 (miRNA145) promoter activity. Finally, we provide evidence that EWS-FLI-1 and miRNA-145 function in a mutually repressive feedback loop and identify their common target gene, SOX2, in addition to miRNA145 itself, as key players in ESFT cell differentiation and tumorigenicity. Our observations provide insight for the first time into the mechanisms whereby a single oncogene can reprogram primary cells to display a CSC phenotype. [ABSTRACT FROM AUTHOR]