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There are more than 70 distinct sarcomas, and this diversity complicates the development of precision-based therapeutics for these cancers. Prospective comprehensive genomic profiling could overcome this challenge by providing insight into sarcomas' molecular drivers. Through targeted panel sequencing of 7494 sarcomas representing 44 histologies, we identify highly recurrent and type-specific alterations that aid in diagnosis and treatment decisions. Sequencing could lead to refinement or reassignment of 10.5% of diagnoses. Nearly one-third of patients (31.7%) harbor potentially actionable alterations, including a significant proportion (2.6%) with kinase gene rearrangements; 3.9% have a tumor mutational burden ≥10 mut/Mb. We describe low frequencies of microsatellite instability (<0.3%) and a high degree of genome-wide loss of heterozygosity (15%) across sarcomas, which are not readily explained by homologous recombination deficiency (observed in 2.5% of cases). In a clinically annotated subset of 118 patients, we validate actionable genetic events as therapeutic targets. Collectively, our findings reveal the genetic landscape of human sarcomas, which may inform future development of therapeutics and improve clinical outcomes for patients with these rare cancers. Comprehensive molecular profiles are required to understand and treat sarcomas, which comprise more than 70 different subtypes. Here, the authors profile the genomic landscape of 7494 sarcomas across 44 histologies using targeted panel sequencing and identify potential therapeutic targets. [ABSTRACT FROM AUTHOR]

In summary, imaging diagnosis of femoral hernia can be potentially difficult and radiologists must be cognizant of this possible differential diagnosis whenever a cystic lesion is encountered at its characteristic location. Thus, femoral hernia should be considered in the differential diagnoses whenever a cystic groin mass is encountered at or near the femoral ring or canal, inferior to the inguinal ligament between the pubic tubercle and the femoral vein. While the diagnosis of larger femoral hernias containing bowel or peritoneal fat is relatively straightforward, early femoral hernias may contain only peritoneal fluid and can be difficult to distinguish from other cystic lesions on imaging. [Extracted from the article]

We present a unique case of an aggressive scapular osteoblastoma that produced β-hCG as a paraneoplastic manifestation in a 20-year-old woman. Serum β-hCG was found to be elevated during presurgical workup and consequently delayed surgical resection of the increasingly painful tumor because of suspected pregnancy. The paraneoplastic production of β-hCG was later proven by positive immunohistochemical stain of β-hCG in a curettage specimen and normalization of β-hCG levels after surgical resection of the aggressive osteoblastoma. Production of beta-human chorionic gonadotropin (β-hCG) has been reported in several carcinomas and sarcomas but, to our knowledge, it has not been reported in osteoblastoma in the English-language literature. [ABSTRACT FROM AUTHOR]

Objective: Myxofibrosarcoma frequently shows curvilinear extensions of high T2 signal that also enhance on magnetic resonance imaging; these "tails" represent fascial extension of tumor at histopathological examination. This study was performed to determine whether the tail sign is helpful in distinguishing myxofibrosarcoma from other myxoid-containing neoplasms.Materials and Methods: The study group consisted of 44 patients with pathologically proven myxofibrosarcoma; the control group consisted of 52 patients with a variety of other myxoid-predominant tumors. Three musculoskeletal radiologists independently evaluated T2-weighted (and/or short-tau inversion recovery) and post-contrast MR images for the presence of one or more enhancing, high-signal intensity, curvilinear projections from the primary mass. Sensitivity and specificity for the diagnosis of myxofibrosarcoma were calculated for each reader. Interobserver variability was assessed with kappa statistic and percentage agreement.Results: A tail sign was deemed present in 28, 30, and 34 cases of myxofibrosarcoma and in 11, 9, and 5 of the controls for the three readers respectively, yielding a sensitivity of 64-77 % and a specificity of 79-90 %. The interobserver agreement was moderate-to-substantial (kappa=0.626).Conclusion: The tail sign at MRI is a moderately specific and sensitive sign for the diagnosis of myxofibrosarcoma relative to other myxoid-containing tumors. [ABSTRACT FROM AUTHOR]

Chordoma and chondrosarcoma are malignant bone tumors characterized by the abundant production of extracellular matrix. The resistance of these tumors to conventional therapeutic modalities has prompted us to delineate the gene expression profile of these two tumor types, with the expectation to identify potential molecular therapeutic targets. Furthermore the transcriptional profile of chordomas and chrondrosarcomas was compared to a wide variety of sarcomas as well as to that of normal tissues of similar lineage, to determine whether they express unique gene signatures among other tumors of mesenchymal origin, and to identify changes associated with malignant transformation. A HG-U133A Affymetrix Chip platform was used to determine the gene expression signature in 6 chordoma and 14 chondrosarcoma lesions. Validation of selected genes was performed by qPCR and immunohistochemistry (IHC) on an extended subset of tumors. By unsupervised clustering, chordoma and chondrosarcoma tumors grouped together in a genomic cluster distinct from that of other sarcoma types. They shared overexpression of many extracellular matrix genes including aggrecan, type II & X collagen, fibronectin, matrillin 3, high molecular weight-melanoma associated antigen ( HMW-MAA), matrix metalloproteinase MMP-9, and MMP-19. In contrast, T Brachyury and CD24 were selectively expressed in chordomas, as were Keratin 8,13,15,18 and 19. Chondrosarcomas are distinguished by high expression of type IX and XI collagen. Because of its potential usefulness as a target for immunotherapy, the expression of HMW-MAA was analyzed by IHC and was detected in 62% of chordomas and 48% of chondrosarcomas, respectively. Furthermore, western blotting analysis showed that HMW-MAA synthesized by chordoma cell lines has a structure similar to that of the antigen synthesized by melanoma cells. In conclusion, chordomas and chondrosarcomas share a similar gene expression profile of up-regulated extracellular matrix genes. HMW-MAA represents a potential useful target to apply immunotherapy to these tumors. [ABSTRACT FROM AUTHOR]