High frequency of MYC gene amplification is a common feature of radiation-induced sarcomas. Further results from EORTC STBSG TL 01/01

Recurrent benign fibrous histiocytoma of the bone benefits from denosumab followed by malignant transformation: a case report

Benign fibrous histiocytoma of the bone (BFHB) is a rare mesenchymal tumor, representing less than 1% of all benign bone tumors. This controversial entity is characterized by a mixture of fibroblasts arranged in a storiform pattern, varying amounts of osteoclast-type giant cells and foamy macrophages. Curettage or simple resection is usually curative. However, it was reported that up to 11% of the patients suffer from relapse. Here, we report a case of malignant transformation of BFHB after long-lasting disease stabilization under denosumab therapy.

Proteomic profiling of canine fibrosarcoma and adjacent peritumoral tissue

Fibrosarcoma (FSA) are rare soft tissue tumors that display aggressive local behavior and invasive growth leading to high rates of tumor recurrence. While the low incidence in humans hampers detailed understanding of the disease, FSA are frequent in dogs and present potential models for the human condition. However, a lack of in-depth molecular characterization of FSA and unaffected peritumoral tissue (PTT) in both species impedes the translational potential of dogs. To address this shortcoming, we characterized canine FSA and matched skeletal muscle, adipose and connective tissue using laser-capture microdissection (LCM) and LC-MS/MS in 30 formalin-fixed paraffin embedded (FFPE) specimens. Principal component analysis of 3'530 different proteins detected across all samples clearly separates the four tissues, with several targets strongly differentiating tumor from all three PTTs. 25 proteins were exclusively found in tumor tissue in ≥80% of cases. Among these, CD68 (a macrophage marker), Optineurin (OPTN), Nuclear receptor coactivator 5 (NCOA5), RAP1GDS1 (Rap1 GTPase-GDP dissociation stimulator 1) and Stromal cell derived factor 2 like 1 (SDF2L1) were present in ≥90% of FSA. Protein expression across all FSA was highly homogeneous and characterized by MYC and TP53 signaling, hyperactive EIF2 and immune-related changes as well as strongly decreased oxidative phosphorylation and oxidative lipid metabolism. Finally, we demonstrate significant molecular homology between canine FSA and human soft-tissue sarcomas, emphasizing the relevance of studying canine FSA as a model for human FSA. In conclusion, we provide the first detailed overview of proteomic changes in FSA and surrounding PTT with relevance for the human disease.

Clinical and Pathologic Characterization of 94 Radiation-Associated Sarcomas: Our Institutional Experience

Radiation-associated sarcomas are an uncommon complication of therapeutic radiation. However, their prevalence has increased with the more widespread use of this treatment modality. The clinical, pathologic and genetic characteristics of radiation-associated sarcomas are not fully understood. In this study we describe the features of 94 radiation-associated sarcomas reviewed at our institution between 1993 and 2018, evaluate their overall survival (OS) and progression-free survival (PFS) outcomes, and compare them with their sporadic counterparts reviewed within the same time period. Histologic subtypes of all radiation-associated sarcomas included 31 (33%) undifferentiated sarcomas, 20 (21%) osteosarcomas, 17 (18%) angiosarcomas, 10 (11%) malignant peripheral nerve sheath tumor (MPNST), 9 (10%) leiomyosarcomas, 4 (4%) myxofibrosarcomas, and 3 (3%) rhabdomyosarcomas. Six patients had a documented cancer predisposition syndrome. The most common preceding neoplasms included adenocarcinoma (47%) and squamous cell carcinoma (19%), with a mean latency of 13 years. Multivariable Cox survival analysis demonstrated that advanced stage at diagnosis based on pT category (AJCC eighth edition) and fragmented resection were associated with worse survival outcomes. In addition, there was a statistically significant difference in PFS between radiation-associated undifferentiated sarcomas and MPNST when compared to their sporadic counterparts using the Kaplan-Meier method and Log-rank analysis. Overall, our study shows that radiation-associated sarcomas comprise a wide clinico-pathologic spectrum of disease, with a tendency for aggressive clinical behavior. This study further delineates the understanding of these uncommon diseases. Future studies are necessary to better understand the genetic and epigenetic changes that drive the differences in behavior between these tumors and their sporadic counterparts, and to offer better treatment options.

Differences in potential key genes and pathways between primary and radiation-associated angiosarcoma of the breast

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Angiosarcoma of the breast is a high-grade malignant soft tissue tumor, it can be divided into primary and secondary.

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The differences between primary and secondary angiosarcomas in terms of pathogenesis, clinical behavior, early diagnosis biomarkers, genetic abnormalities, and therapeutic targets remain to be fully elucidated.

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Due to its rarity, most of the current information relating to angiosarcoma is provided by case reports and single-institution retrospective cohort studies and the research with large-scale genomic studies published to date are very limited.

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We identified the differentially expressed genes (DEGs) between primary and second breast angiosarcomas and identified the hub genes as well as predicted novel biomarkers, pathways, and potential therapeutic targets for primary and secondary breast angiosarcomas.

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We aimed to identify novel biomarkers, pathways, and potential therapeutic targets for primary and secondary breast angiosarcomas to facilitate future research.

Background

Angiosarcoma of the breast is a high-grade malignant soft tissue tumor, it can be divided into primary and radiation-associated angiosarcoma(secondary). However, the differences between primary and secondary angiosarcomas in terms of pathogenesis, clinical behavior, early diagnosis biomarkers, genetic abnormalities, and therapeutic targets remain to be fully elucidated. At the same time, due to its rarity, most of current information relating to angiosarcoma is provided by case reports. Therefore, exploring the mechanisms of primary and secondary breast angiosarcoma have important value for the discovery of new biomarkers and research into potential therapeutic targets.

Methods

The differentially expressed genes (DEGs) between 36 cases of primary angiosarcoma and 54 cases of secondary angiosarcoma were screened. Then, the DEGs were used to gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Then, a protein-protein interaction (PPI) network was constructed using the STRING database.

Results

A total of 18 DEGs were identified, of which 13 were upregulated and 5 were downregulated in secondary breast angiosarcoma. The GO enrichment analysis showed that the DEGs were most enriched in metabolism, energy pathways, and protein metabolism in biological processes. The enriched signaling pathways of DEGs were the transforming growth factor-β (TGF-β), Wnt, Hippo and PI3K-Akt signaling pathways. Then, the PPI network was conducted and hub genes were identified and they were involved in thyroid hormone, Hippo and other signaling pathways.

Conclusion

This study lay the foundation for the discovery of effective and reliable molecular biomarkers and essential therapeutic targets for these malignancies.

Low-Dose Radiation Can Cause Epigenetic Alterations Associated With Impairments in Both Male and Female Reproductive Cells

Humans are regularly and continuously exposed to ionizing radiation from both natural and artificial sources. Cumulating evidence shows adverse effects of ionizing radiation on both male and female reproductive systems, including reduction of testis weight and sperm count and reduction of female germ cells and premature ovarian failure. While most of the observed effects were caused by DNA damage and disturbance of DNA repairment, ionizing radiation may also alter DNA methylation, histone, and chromatin modification, leading to epigenetic changes and transgenerational effects. However, the molecular mechanisms underlying the epigenetic changes and transgenerational reproductive impairment induced by low-dose radiation remain largely unknown. In this study, two different types of human ovarian cells and two different types of testicular cells were exposed to low dose of ionizing radiation, followed by bioinformatics analysis (including gene ontology functional analysis and Ingenuity Pathway Analysis), to unravel and compare epigenetic effects and pathway changes in male and female reproductive cells induced by ionizing radiation. Our findings showed that the radiation could alter the expression of gene cluster related to DNA damage responses through the control of MYC. Furthermore, ionizing radiation could lead to gender-specific reproductive impairment through deregulation of different gene networks. More importantly, the observed epigenetic modifications induced by ionizing radiation are mediated through the alteration of chromatin remodeling and telomere function. This study, for the first time, demonstrated that ionizing radiation may alter the epigenome of germ cells, leading to transgenerational reproductive impairments, and correspondingly call for research in this new emerging area which remains almost unknown.

The impact of MYC amplification on clinicopathologic features and prognosis of radiation-associated angiosarcomas of the breast

AIMS

Radiation-associated angiosarcomas (RT-AS) of the breast are rare tumours with poor prognosis. MYC amplification is considered the hallmark of RT-AS and is sometimes used as a diagnostic tool to distinguish from other radiation-associated vascular lesions. However, a small subset of RT-AS lacks MYC amplification, which may be associated with better outcome. Loss of H3K27me3 expression by immunohistochemistry (IHC) has been recently postulated as an additional diagnostic marker for RT-AS. This study aimed to evaluate the impact of MYC amplification as detected by fluorescence in situ hybridization and/or next-generation sequencing on clinicopathologic features and outcome in a large cohort of RT-AS, compare outcome with radiation-associated sarcomas of the breast (RT-S) other than angiosarcoma, and evaluate expression of H3K27me3 IHC in these groups.

METHODS AND RESULTS

Eighty-one RT-AS were identified, including 73 MYC amplified and 8 (10%) non-amplified. MYC amplified RT-AS were diagnosed in older patients (median age 69 vs 61 years). The 5-year disease specific survival and overall survival were 56% and 47%, respectively. Older age, larger tumour size, positive margin and MYC amplification were associated with worse prognosis. None of the RT-AS showed complete loss of H3K27me3 IHC expression. All 18 RT-S were MYC non-amplified, and complete loss of H3K27me3 expression was seen in 2. We found no difference in prognosis between RT-AS and RT-S.

CONCLUSIONS

RT-AS is associated with a poor prognosis. Older age at diagnosis, larger tumour size, positive margin at excision and MYC amplification are associated with worse prognosis.

Protection against chemotherapy- and radiotherapy-induced side effects: A review based on the mechanisms and therapeutic opportunities of phytochemicals

BACKGROUND

Although great achievements have been made in the field of cancer therapy, chemotherapy and radiotherapy remain the mainstay cancer therapeutic modalities. However, they are associated with various side effects, including cardiocytotoxicity, nephrotoxicity, myelosuppression, neurotoxicity, hepatotoxicity, gastrointestinal toxicity, mucositis, and alopecia, which severely affect the quality of life of cancer patients. Plants harbor a great chemical diversity and flexible biological properties that are well-compatible with their use as adjuvant therapy in reducing the side effects of cancer therapy.

PURPOSE

This review aimed to comprehensively summarize the molecular mechanisms by which phytochemicals ameliorate the side effects of cancer therapies and their potential clinical applications.

METHODS

We obtained information from PubMed, Science Direct, Web of Science, and Google scholar, and introduced the molecular mechanisms by which chemotherapeutic drugs and irradiation induce toxic side effects. Accordingly, we summarized the underlying mechanisms of representative phytochemicals in reducing these side effects.

RESULTS

Representative phytochemicals exhibit a great potential in reducing the side effects of chemotherapy and radiotherapy due to their broad range of biological activities, including antioxidation, antimutagenesis, anti-inflammation, myeloprotection, and immunomodulation. However, since a majority of the phytochemicals have only been subjected to preclinical studies, clinical trials are imperative to comprehensively evaluate their therapeutic values.

CONCLUSION

This review highlights that phytochemicals have interesting properties in relieving the side effects of chemotherapy and radiotherapy. Future studies are required to explore the clinical benefits of these phytochemicals for exploitation in chemotherapy and radiotherapy.

MYC expression has limited utility in the distinction of undifferentiated radiation-associated sarcomas from sporadic sarcomas and sarcomatoid carcinoma

AIMS

MYC is a proto-oncogene that is frequently dysregulated in various malignancies, through translocation or amplification. Radiation-associated angiosarcoma frequently shows MYC amplification, and immunohistochemical expression has been shown to be a reliable surrogate marker for amplification, but less is known about MYC expression in other sarcoma types, despite reports of MYC amplification in some undifferentiated/unclassified radiation-associated sarcomas (RASs). Distinguishing putative RAS from non-radiation-associated sarcoma or sarcomatoid carcinoma can be difficult. The aim of this study was to determine the prevalence and potential diagnostic utility of MYC in this context, by evaluating MYC expression in a cohort of RASs, non-radiation-associated sarcomas, and sarcomatoid carcinomas.

METHODS AND RESULTS

Three hundred and eighty-five neoplasms were evaluated, including 81 RASs (18 angiosarcomas; 57 undifferentiated sarcomas; three leiomyosarcomas; and three malignant peripheral nerve sheath tumours), 267 non-radiation-associated sarcomas, and 37 sarcomatoid carcinomas. Immunohistochemistry was performed with a monoclonal anti-MYC antibody. Staining in tumour cells was scored on the basis of extent (focal, 1-4%; multifocal, 5-49%; and diffuse, ≥50%) and intensity (strong, moderate, and weak). One hundred percent of radiation-associated angiosarcomas expressed MYC diffusely. Expression was infrequent among other types of RAS (9.5%), and the frequency was similar to that in non-radiation-associated sarcomas (9.7%). MYC expression was more common in sarcomatoid carcinomas, occurring in 43%. The extent and intensity of staining were variable in all groups.

CONCLUSION

MYC expression is infrequent among RASs other than angiosarcoma, and has a similar prevalence in sporadic sarcomas. Given the frequency of expression in sarcomatoid carcinomas, MYC expression outside the context of radiation-associated angiosarcoma is of limited diagnostic utility, and should be interpreted with caution after exclusion of sarcomatoid carcinoma where relevant.

Genomic and transcriptomic comparison of post-radiation versus sporadic sarcomas

Post-radiation sarcomas are rare secondary cancers arising from radiation therapies. To date, few genetic specificities have been described for such malignancies and the oncogenesis of sarcomas with complex genetics (both sporadic and post-radiation) remains largely misunderstood. We performed genomic and transcriptomic analyses on 77 post-radiation sarcomas using DNA-array and RNA sequencing. Consequently, we were able to investigate changes in copy number variations, transcriptome profiling, fusion gene expression, and mutational landscapes. We compare these data to a reference cohort of 93 sporadic sarcomas. At genomic level, similar chromosomal complexity was observed both in post-radiation and sporadic sarcomas with complex genetics. We found more frequent CDKN2A and CDKN2B (coding for p14/p16 and p15 proteins, respectively; at 9p21.3) losses in post-radiation (71%) than in sporadic tumors (39%; P = 6.92e-3). Among all detected fusion genes and punctual variations, few specificities were observed between these groups and such alterations are not able to drive a strong and specific oncogenesis. Recurrent MYC amplifications (96%) and KDR variants (8%) were detected in post-radiation angiosarcomas, in agreement with the literature. Transcriptomic analysis of such angiosarcomas revealed two distinct groups harboring different genomic imbalances (in particular gains of 17q24.2-17qter) with different clinical courses according to patient's vital status. Differential gene expression analysis permitted to focus on the immune response as a potential actor to tumor aggressiveness. Histochemistry validated a lower inflammation and lower immune infiltrate at tumor periphery for highly aggressive angiosarcomas. Our results provide new genomic and transcriptomic information about post-radiation sarcomas. The techniques we used (RNA-seq and DNA-arrays) did not highlight major differences in sarcomas with complex genetics depending on the radiation context, revealing similar patterns of transcriptomic profiles and chromosomal copy number variations. Additional characterizations, particularly whole genome sequencing, could measure changes in DNA following radiation therapy in such malignancies and may precise their oncogenesis.

EASL Clinical Practice Guideline: Occupational liver diseases

A variety of chemicals have been linked to occupational liver diseases, including several solvents and mixtures thereof, pesticides, and metals. Workplace exposures have been associated with virtually the entire spectrum of acute and chronic liver diseases. However, their prevalence is inadequately quantified and their epidemiology limited. Occupational liver diseases may result from high accidental or from prolonged lower level exposures. Whereas the former is uncommon and easily recognised, the latter are relatively more frequent but often overlooked because they may display normal values of conventional markers, have an insidious onset and be asymptomatic or be obfuscated and confounded by concurrent conditions. In addition, specific tests of toxicity are not available, histopathology may not be revealing and the assessment of internal dose of chemicals is usually not decisive. Given these circumstances, the diagnosis of these liver disorders is challenging, one of exclusion and often requires an interdisciplinary approach. These recommendations offer a classification of the type of liver injuries associated with occupational exposures - based in part on the criteria for drug-induced liver injury - a grading of their severity, and the diagnostic and preventive criteria for chemically induced occupational liver disease.

Radiation-Associated Sarcomas: An Update on Clinical, Histologic, and Molecular Features

Approximately half of all cancer patients receive radiation therapy as part of their oncologic treatment. Radiation-associated sarcomas occur in fewer than 1% of patients who receive radiation therapy but account for up to 5% of all sarcomas. As the use of radiation has increased in the past few decades and overall oncologic outcomes are improving, the incidence of radiation-associated sarcomas is also expected to increase. Historically, radiation-associated sarcomas have been associated with poor outcomes but recent data suggest the prognosis is improving. Distinguishing the sarcoma from the primary malignancy is a major diagnostic criterion.

Radiation-Induced Sarcoma following Prolonged Coronary Stent Placement

Radiation exposure for the average coronary stent placement varies based on a number of factors but typically amounts to 6-11 mSv per patient (compared to 3 mSv background). As with all procedures which utilize radiation, there is an inherent risk of genetic mutation and the possible development of malignancy. Here, we present the case of a 75-year-old male who presented with an exophytic mass on his back following prolonged coronary catheterization with a radiation burn seven years prior. Biopsy of the lesion revealed the mass was consistent with an undifferentiated pleomorphic sarcoma emanating from the site of the radiation burn. After staging studies demonstrated no evidence of metastatic disease, radical excision with negative margins was performed. This case demonstrates that despite the rarity of radiation injury, each incidence necessitates strict monitoring of radiation exposure and continual follow-up due to the risk of malignancy.

MYC gene amplification is a rare event in atypical fibroxanthoma and pleomorphic dermal sarcoma

Atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS) are rare malignancies typically occurring in elderly patients and predominantly located in skin regions exposed to UV-light. Thus, a role of UV-radiation-induced damage for AFX and PDS tumorigenesis has been postulated. MYC gene amplification has been demonstrated as a distinctive feature of radiation-induced angiosarcoma. In order to investigate whether chronic exposure to UV-light might also lead to MYC copy number changes, 51 AFX and 24 PDS samples were retrospectively analyzed for MYC amplification by fluorescence in situ hybridization using a MYC and a CEP8 gene probe. Of the 44 analyzable AFX samples, one case showed MYC amplification (defined as a MYC/CEP8 ratio ≥2.0), whereas 13 cases demonstrated low level copy number gains (defined as MYC/CEP8 ratio ≥ 1.2-< 2.0). MYC amplification was seen in an AFX sample of extraordinary tumor thickness of 17.5 mm (vs. median 3.25 mm for all samples). Of the 24 PDS cases, five specimen demonstrated MYC low level copy number gains. Immunohistochemically, neither the AFX nor the PDS cases showed MYC protein expression. In summary, these findings rule out that MYC amplification is a major genetic driver in the process of AFX or PDS tumorigenesis. However, MYC amplification may occur as a late event during AFX development and hence might only be detectable in advanced, thick lesions.

The 2015 World Health Organization Classification of Tumors of the Thymus: Continuity and Changes

This overview of the 4th edition of the World Health Organization (WHO) Classification of thymic tumors has two aims. First, to comprehensively list the established and new tumor entities and variants that are described in the new WHO Classification of thymic epithelial tumors, germ cell tumors, lymphomas, dendritic cell and myeloid neoplasms, and soft-tissue tumors of the thymus and mediastinum; second, to highlight major differences in the new WHO Classification that result from the progress that has been made since the 3rd edition in 2004 at immunohistochemical, genetic and conceptual levels. Refined diagnostic criteria for type A, AB, B1-B3 thymomas and thymic squamous cell carcinoma are given, and it is hoped that these criteria will improve the reproducibility of the classification and its clinical relevance. The clinical perspective of the classification has been strengthened by involving experts from radiology, thoracic surgery, and oncology; by incorporating state-of-the-art positron emission tomography/computed tomography images; and by depicting prototypic cytological specimens. This makes the thymus section of the new WHO Classification of Tumours of the Lung, Pleura, Thymus and Heart a valuable tool for pathologists, cytologists, and clinicians alike. The impact of the new WHO Classification on therapeutic decisions is exemplified in this overview for thymic epithelial tumors and mediastinal lymphomas, and future perspectives and challenges are discussed.

"Hockey Stick" may Strike Back: Hepatocellular Carcinoma on Noncirrhotic Liver as a Late Toxicity of Lombo-Aortic Radiotherapy for Seminoma. A Review Triggered by an Unusual Case

Most patients with testicular seminoma have been treated with a curative intent for decades. Second cancers after radiotherapy for testicular seminoma before 1990 are a growing issue, and are related to previous generation of dose planning and delineating strategies. Among those cancers, hepatocellular carcinoma is an extremely rare occurrence, especially when affecting patients with healthy, noncirrhotic liver. Here, we describe such a case in a patient of our institution, and subsequently review the relevant literature and large epidemiologic studies. Understanding those late and serious toxicity features may help cancer care teams to screen and treat those patients appropriately.

Radiation-Induced Sarcoma: A 15-Year Experience in a Single Large Tertiary Referral Center

Purpose

The purpose of this study is to report on the incidence and the experience in management of radiation-induced sarcoma (RIS) at a large single center in Korea for 15 years.

Materials and Methods

We retrospectively reviewed the sarcoma registry of a large institution from January 2000 to April 2014.

Results

Out of the 3,674 patients listed in the registry, 33 patients (0.9%) diagnosed with RIS were identified. The median latency of RIS was 12.1 years. The number of cases of RIS increased from four cases in the years 2000-2003 to 14 cases in the years 2012-2014. The most common histology was osteosarcoma (36.4%). The median follow-up period was 23.1 months, the median overall survival (OS) of all patients was 2.9 years, and their 5-year survival rate was 44.7%. Univariate and multivariate analyses showed association of the age at diagnosis (p=0.01) and the treatment aim (p=0.001) with the OS. The median OS and the 5-year survival rate of patients treated with curative surgery (n=19) were 9.6 years and 65%, respectively, and of the conservatively treated patients, 0.7 years and 0% (n=14). Re-irradiation was delivered to nine patients, and radiation toxicity was observed in five patients.

Conclusion

In this study, RIS accounted for 0.9% of the cases of sarcoma, with increasing incidence. Despite the association of curative resection with increased survival, it could be applied to only 58% of the patients. Considering the limited treatment options for RIS, conduct of a genetic study to identify the underlying mechanism of RIS is needed.

Does radiation-induced c-MYC amplification initiate breast oncogenesis?

The MYC (v-myc avian myelocytomatosis viral oncogene homolog; c-MYC) locus on chromosome 8q is susceptible to high-level amplification following exposure of human breast cells to ionizing radiation, and c-MYC amplification is a common feature of both radiogenic adenocarcinoma and radiogenic angiosarcoma of the breast. Taken together, these observations suggest common breast-specific susceptibility factors that predispose cells to amplification of this critical proto-oncogene and the development of radiogenic cancer in multiple tissue types of this radiosensitive organ.

Key roles for MYC, KIT and RET signaling in secondary angiosarcomas

Background:

Angiosarcomas may develop as primary tumours of unknown cause or as secondary tumours, most commonly following radiotherapy to the involved field. The different causative agents may be linked to alternate tumorigenesis, which led us to investigate the genetic profiles of morphologically indistinguishable primary and secondary angiosarcomas.

Methods:

Whole-genome (18k) c-DNA-mediated annealing, selection, extension and ligation analysis was used to genetically profile 26 primary and 29 secondary angiosarcomas. Key findings were thereafter validated using RT–qPCR, immunohistochemistry and validation of the gene signature to an external data set.

Results:

In total, 103 genes were significantly deregulated between primary and secondary angiosarcomas. Secondary angiosarcomas showed upregulation of MYC, KIT and RET and downregulation of CDKN2C. Functional annotation analysis identified multiple target genes in the receptor protein tyrosine kinase pathway. The results were validated using RT–qPCR and immunohistochemistry. Further, the gene signature was applied to an external data set and, herein, distinguished primary from secondary angiosarcomas.

Conclusions:

Upregulation of MYC, KIT and RET and downregulation of CDKN2C characterise secondary angiosarcoma, which implies possibilities for diagnostic application and a mechanistic basis for therapeutic evaluation of RET-kinase-inhibitors in these highly aggressive tumours.

Soft tissue sarcomas--new approaches to diagnosis and classification

The study of sarcoma pathology is a rapidly evolving field. The continued refinement of classic diagnostic techniques in conjunction with the molecular diagnostics has resulted in an abundance of data regarding this diverse and rare group of tumors. We anticipate that cutting edge technology including next generation sequencing will continue to further our understanding of saromagenesis and enable more precise classification and diagnosis of sarcomas in the future.

Aberrations in Angiogenic Signaling and MYC Amplifications are Distinguishing Features of Angiosarcoma

Angiosarcomas are very aggressive, rare malignant tumors that originate from vascular or lymphatic vessels and primarily occur following chemical exposure or radiation therapy. Tumor response to either chemotherapy, radiation, or novel anti-angiogenic therapeutics is very low, and because little is known regarding the aberrant signaling that controls these tumors, personalized treatment options for many of these patients are lacking. In this review, we summarize several recent findings regarding the genomics of angiosarcomas, including new discoveries regarding aberrant angiogenic signaling and Myc amplification as key features of this tumor type.