Soft-tissue and bone tumors represent a heterogeneous group of tumors encompassing more than 100 histologic subtypes today. Identifying genetic aberrations increasingly is important in these tumors for accurate diagnosis. Although gene mutations typically are detected by second-generation sequencing, the identification of structural variants (SVs) and copy number alterations (CNAs) remains challenging and requires various cytogenetic techniques including karyotyping, fluorescence in situ hybridization, and arrays, each with important limitations.
View Article and Find Full Text PDFUndifferentiated mesenchymal tumors from the intimal layer (intimal sarcomas) are rare within the ventricles and exceptional in children. A rare case of an intimal sarcoma located in the right ventricle in a young child is presented with need for urgent surgical resection due to mechanical flow obstruction. Tumor cells showed amplification of gene and a homozygous loss of on 9p21.
View Article and Find Full Text PDFA clinically relevant subset of patients with soft tissue sarcoma presents with either locally advanced or upfront metastatic disease, or will develop distant metastases over time, despite successful treatment of their primary tumour. The currently available systemic agents to treat such advanced cases only provide modest disease control and are not active in all histological subtypes. Thus, there is an unmet need for novel and more efficacious agents to improve the outcome of this rare disease.
View Article and Find Full Text PDFAlveolar soft part sarcoma (ASPS) is a rare subtype of soft tissue sarcoma characterized by an unbalanced translocation, resulting in ASPSCR1-TFE3 fusion that transcriptionally upregulates expression. The European Organization for Research and Treatment of Cancer (EORTC) 90101 "CREATE" phase II trial evaluated the MET inhibitor crizotinib in ASPS patients, achieving only limited antitumor activity. We performed a comprehensive molecular analysis of ASPS tissue samples collected in this trial to identify potential biomarkers correlating with treatment outcome.
View Article and Find Full Text PDFHigh-level amplification of MDM2 and other genes in the 12q13-15 locus is a hallmark genetic feature of well-differentiated and dedifferentiated liposarcomas (WDLPS and DDLPS, respectively). Detection of this genomic aberration in plasma cell-free DNA may be a clinically useful assay for non-invasive distinction between these liposarcomas and other retroperitoneal tumors in differential diagnosis, and might be useful for the early detection of disease recurrence. In this study, we performed shallow whole genome sequencing of cell-free DNA extracted from 10 plasma samples from 3 patients with DDLPS and 1 patient with WDLPS.
View Article and Find Full Text PDFClear cell sarcoma (CCSA) is characterized by a chromosomal translocation leading to rearrangement, resulting in aberrant transcription of multiple genes, including . The EORTC 90101 phase II trial evaluated the MET inhibitor crizotinib in CCSA but resulted in only sporadic responses. We performed an in-depth histopathological and molecular analysis of archival CCSA samples to identify alterations potentially relevant for the treatment outcome.
View Article and Find Full Text PDFPurpose: The European Organization for Research and Treatment of Cancer (EORTC) clinical phase II trial 90101 "CREATE" showed high antitumor activity of crizotinib, an inhibitor of anaplastic lymphoma kinase (ALK)/ROS1, in patients with advanced inflammatory myofibroblastic tumor (IMFT). However, recent findings suggested that other molecular targets in addition to ALK/ROS1 might also contribute to the sensitivity of this kinase inhibitor. We therefore performed an in-depth molecular characterization of archival IMFT tissue, collected from patients enrolled in this trial, with the aim to identify other molecular alterations that could play a role in the response to crizotinib.
View Article and Find Full Text PDFPurpose: European Organisation for Research and Treatment of Cancer (EORTC) 90101 (CREATE) was a prospective, multicentric, non-randomised, open-label phase II basket trial to assess the efficacy and safety of crizotinib in patients with different types of cancers, including advanced inflammatory myofibroblastic tumour (IMT) with or without anaplastic lymphoma kinase (ALK) rearrangements. Here, we report updated results with long-term follow-up.
Patients/methods: After central reference pathology, eligible ALK-positive and ALK-negative patients with advanced/metastatic IMT deemed incurable with surgery, radiotherapy or systemic therapy received oral crizotinib 250 mg twice daily.
Background: Synovial sarcomas (SS) are malignant mesenchymal neoplasms that account for about 10% of all sarcomas. Complete surgical excision is the mainstay of primary treatment for localized disease, but SS have a high tendency for local relapse and metastases. Metastatic disease is commonly treated with systemic chemotherapy.
View Article and Find Full Text PDFLoss of chromosome 9p21 is observed in one-thirds of clear-cell renal cell carcinoma (ccRCC) and is associated with poorer patient survival. Unexpectedly, 9p21 LOH does not lead to decreased expression of the 9p21 tumor suppressor genes, and , suggesting alternative mechanisms of 9p-mediated tumorigenesis. Concordantly, CRISPR-mediated 9p21 deletion promotes growth of immortalized human embryonic kidney epithelial cells independently of the CDKN2A/B pathway inactivation.
View Article and Find Full Text PDFWithin sarcomas 50 different histological subtypes exist, each with their own molecular and clinical characteristics. The combination of tumor subtype heterogeneity and often a limited number of clinical cases make detailed molecular sarcoma studies challenging, particularly when focusing on individual cohorts. However, the increasing number of publicly available genomics data opens inroads to overcome this obstacle.
View Article and Find Full Text PDFMutational analysis guides therapeutic decision making in patients with advanced-stage gastrointestinal stromal tumors (GISTs). We evaluated three targeted next-generation sequencing (NGS) assays, consecutively used over 4 years in our laboratory for mutational analysis of 162 primary GISTs: Agilent GIST MASTR, Illumina TruSight 26 and an in-house developed 96 gene panels. In addition, we investigated the feasibility of a more comprehensive approach by adding targeted RNA sequencing (Archer FusionPlex, 11 genes) in an attempt to reduce the number of Wild Type GISTs.
View Article and Find Full Text PDFThe majority of patients with gastrointestinal stromal tumors (GIST) eventually become resistant with time due to secondary mutations in the driver receptor tyrosine kinase. Novel treatments that do not target these receptors may therefore be preferable. For the first time, we evaluated a tubulin inhibitor, plocabulin, in patient-derived xenograft (PDX) models of GIST, a disease generally considered to be resistant to cytotoxic agents.
View Article and Find Full Text PDFMyxoinflammatory fibroblastic sarcoma (MIFS) is a rare, low-grade soft tissue neoplasm preferentially arising in the extremities of young to middle-aged adults characterized histologically by a variegated appearance and absence of a distinctive immunophenotype. Herein we have evaluated a series of 73 cases of MIFS to define potential features and markers that may facilitate diagnosis. An immunohistochemical study with a large panel of antibodies showed strong positivity of the tumor cells for bcl-1 (94.
View Article and Find Full Text PDFThe majority of gastrointestinal stromal tumors (GISTs) are driven by oncogenic KIT signaling and can therefore be effectively treated with the tyrosine kinase inhibitor (TKI) imatinib mesylate. However, most GISTs develop imatinib resistance through secondary KIT mutations. The type of resistance mutation determines sensitivity to approved second-/third-line TKIs but shows high inter- and intratumoral heterogeneity.
View Article and Find Full Text PDFThe results of local-regional advanced melanoma (stage III) management are still not satisfactory. Particularly, there is no personalized treatment in stage III melanoma patients due to the lack of useful classical pathological markers for prognostication of indolent or aggressive course of the disease. The aim of this study was to explore melanoma genomic landscape by means of the mutational profiling of 50 genes influencing carcinogenesis pathways in the randomly selected 93 kinase inhibitor-naïve (KI-naïve) stage III patients.
View Article and Find Full Text PDFPrimary cardiac sarcomas are rare tumors with poor prognosis. Intimal sarcoma, a mesenchymal malignant tumor described mainly in the great vessels, may rarely involve the heart. Herein we describe the case of a 70-years-old female who was found to have a left atrial mass during an investigation of a new onset dyspnea.
View Article and Find Full Text PDFBackground: Soft tissue sarcoma (STS) comprises a family of rare, heterogeneous tumors of mesenchymal origin. Single-agent doxorubicin remains the first-line standard-of-care treatment for advanced and inoperable STS, but response rates are only around 15%. In 2016, phase Ib/II clinical trial results reported an overall survival benefit of 11.
View Article and Find Full Text PDFDespite the success of imatinib in advanced gastrointestinal stromal tumor (GIST) patients, 50% of the patients experience resistance within two years of treatment underscoring the need to get better insight into the mechanisms conferring imatinib resistance. Here the microRNA and mRNA expression profiles in primary (imatinib-naïve) and imatinib-resistant GIST were examined. Fifty-three GIST samples harboring primary KIT mutations (exon 9; n = 11/exon 11; n = 41/exon 17; n = 1) and comprising imatinib-naïve (IM-n) (n = 33) and imatinib-resistant (IM-r) (n = 20) tumors, were analyzed.
View Article and Find Full Text PDFBackground: Liposarcoma (LPS) is a common subtype of soft tissue sarcoma. We describe the clinical outcome of patients with advanced LPS treated in a tertiary referral center and explore potential prognostic factors.
Patients And Methods: We retrospectively reviewed the records of patients with inoperable or metastatic dedifferentiated liposarcoma (DDLPS), myxoid/round cell liposarcoma (MLPS), and pleomorphic liposarcoma (PLPS) diagnosed and/or treated at the University Hospitals Leuven, Leuven, Belgium, between 2000 and 2014.
Soft-tissue sarcomas (STS) represent a heterogeneous group of rare, malignant tumors of mesenchymal origin. Reliable sarcoma research models are scarce. We aimed to establish and characterize histologically and molecularly stable patient-derived xenograft (PDX) models from a broad variety of STS subtypes.
View Article and Find Full Text PDFWe report a very uncommon case of a primary, non-metastatic gastrointestinal stromal tumor (GIST) arising in the prostate gland in a 60-year-old patient. The morphology and immunohistochemical profile of the disease resembled GIST of gastrointestinal origin, and the molecular driver of this malignancy was a double mutation in exons 11 and 13 of the KIT gene. The tumor was proliferating slowly, did respond to neoadjuvant therapy with the KIT-inhibiting agent imatinib and was cured by radical, retro-pubic prostatectomy followed by adjuvant imatinib treatment.
View Article and Find Full Text PDFPurpose: The preoperative distinction between uterine leiomyoma (LM) and leiomyosarcoma (LMS) is difficult, which may result in dissemination of an unexpected malignancy during surgery for a presumed benign lesion. An assay based on circulating tumor DNA (ctDNA) could help in the preoperative distinction between LM and LMS. This study addresses the feasibility of applying the two most frequently used approaches for detection of ctDNA: profiling of copy number alterations (CNAs) and point mutations in the plasma of patients with LM.
View Article and Find Full Text PDFBACKGROUND Intimal sarcoma (IS) is a malignant mesenchymal tumor with predominantly intraluminal growth in large vessels and the heart. Due to the rarity of cases it often poses diagnostic problems in clinical and pathological settings. Although the classification of IS is still controversial, undifferentiated type of IS has recently been found to show immunohistochemical positivity with MDM2, CDK4, or PDGFRA and amplification of MDM2/CDK4 and PDGFRA.
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