Coactivated platelet-derived growth factor receptor {alpha} and epidermal growth factor receptor are potential therapeutic targets in intimal sarcoma

Sarcoma of the Lung and Mediastinum

Primary sarcoma of the lung and mediastinum is rare. The diagnosis requires careful exclusion of sarcomatoid carcinoma, sarcomatoid mesothelioma, and metastases from extra-thoracic sites. This review summarizes the key morphologic, immunohistochemical, and molecular characteristics of sarcomas that are encountered in the lung and mediastinum. The tumor types discussed are synovial sarcoma, well-differentiated/dedifferentiated liposarcoma, myxoid pleomorphic liposarcoma, intimal sarcoma of the pulmonary artery, inflammatory myofibroblastic tumor, epithelioid hemangioendothelioma, primary pulmonary myxoid sarcoma, malignant peripheral nerve sheath tumor, Ewing sarcoma, and CIC-rearranged sarcoma. Relevant differential diagnoses are also addressed.

Case report: Navigating treatment pathways for cardiac intimal sarcoma with PDGFRβ N666K mutation

In the realm of rare cardiac tumors, intimal sarcoma presents a formidable challenge, often requiring innovative treatment approaches. This case report presents a unique instance of primary intimal sarcoma in the left atrium, underscoring the critical role of genomic profiling in guiding treatment. Initial genomic testing unveiled a somatic, active mutation in PDGFRβ (PDGFRβ N666K), accompanied by MDM2 and CDK4 amplifications. This discovery directed the treatment course toward pazopanib, a PDGFRβ inhibitor, following irradiation. The patient's response was remarkable, with the therapeutic efficacy of pazopanib lasting for 16.3 months. However, the patient experienced a recurrence in the left atrium, where subsequent genomic analysis revealed the absence of the PDGFRβ N666K mutation and a significant reduction in PDGFRβ expression. This case report illustrates the complexities and evolving nature of cardiac intimal sarcoma treatment, emphasizing the potential of PDGFRβ signaling as a strategic target and highlighting the importance of adapting treatment pathways in response to genetic shifts.

Pulmonary arterial sarcoma: A case report

RATIONALE

Pulmonary artery sarcoma (PAS) is a rare malignant tumor primarily originating from the pulmonary artery's intima or subintima. Approximately one-third of cases are classified as undifferentiated type. Its clinical manifestations lack specificity, dyspnea is the main symptom but can also present with chest pain, cough, hemoptysis, and other discomforts, making it prone to misdiagnosis as pulmonary embolism (PE).

PATIENT CONCERNS

A 50-year-old woman was admitted to the hospital with "dyspnea for more than 3 months, aggravated for 2 days," and computed tomography pulmonary angiography suggesting "bilateral multiple pulmonary embolisms."

DIAGNOSES

The patient was initially misdiagnosed as PE, and was later definitively diagnosed as undifferentiated pleomorphic sarcoma of the pulmonary artery by pathologic biopsy.

INTERVENTIONS AND OUTCOMES

The patient was initially treated with anticoagulant therapy, but her dyspnea was not relieved. After that, she underwent positron emission computed tomography (PET-CT) and other investigations, which suggested the possibility of PAS, and then she underwent pulmonary endarterectomy to remove the lesion, which relieved her symptoms and was advised to seek further medical attention from the Department of Oncology and Department of Radiotherapy.

LESSONS

PAS can be easily misdiagnosed as PE. If a diagnosis of PE is made, but anticoagulation or even thrombolytic therapy proves ineffective, and there is no presence of PE causative factors such as deep vein thrombosis in the lower extremities, or D-dimer levels are not high, one should be cautious and consider the possibility of PAS.

Stepwise Use of Multimodality Imaging in a Rare Cardiac Intimal Sarcoma

•CISs are rare and aggressive primary cardiac tumors. •CIS presents with diverse pathology and is challenging to manage due to mass effect. •Multimodality cardiac imaging is valuable in diagnosis, surveillance, and management. •Because of limited therapeutic options, earlier diagnosis of CIS is essential.

Intimal Sarcoma with MDM2/CDK4 Amplification and p16 Overexpression: A Review of Histological Features in Primary Tumor and Xenograft, with Immunophenotype and Molecular Profiling

Intimal sarcomas (IS) are rare malignant mesenchymal tumors arising in large blood vessels of the systemic and pulmonary circulation and also in the heart. They are morphologically similar to other spindle cell, poorly differentiated sarcomas. The prognosis is poor and depends mainly on surgical options. Three cases of IS were collected from two institutions. Clinical data were retrieved and histological study was performed. A wide immunohistochemical panel was analyzed. FISH of MDM2 gene was performed, and a molecular study with NGS was implemented in all cases. The mean age of our cases was 54 years. Histologically, the tumors presented a diffuse growth pattern with heterogeneous atypical epithelioid or spindle cells and extensive thrombosed areas. All cases presented intense immunoexpression for MDM2, CDK4, CD117, c-myc, PDGFRA, and p16. PDGFRA, HTERT, and pan-TRK gained expression, while p16 lost intensity, being weaker in both the local recurrences and xenografts. The three cases showed amplification of MDM2 by FISH. NGS analysis revealed amplifications in the CDK4, PDGFRA, and KIT genes, together with BRAF mutation and KRAS amplification. P16 was expressed in all cases, losing intensity in local recurrence and xenografts. Two new alterations, a BRAF mutation and a KRAS amplification, were detected by NGS in different tumors, opening up new therapeutic options for these patients.

The Recent Advances in Molecular Diagnosis of Soft Tissue Tumors

Soft tissue tumors are rare mesenchymal tumors with divergent differentiation. The diagnosis of soft tissue tumors is challenging for pathologists owing to the diversity of tumor types and histological overlap among the tumor entities. Present-day understanding of the molecular pathogenesis of soft tissue tumors has rapidly increased with the development of molecular genetic techniques (e.g., next-generation sequencing). Additionally, immunohistochemical markers that serve as surrogate markers for recurrent translocations in soft tissue tumors have been developed. This review aims to provide an update on recently described molecular findings and relevant novel immunohistochemical markers in selected soft tissue tumors.

Pulmonary artery intimal sarcoma: A rare cause of filling defects in pulmonary arteries

Pulmonary artery intimal sarcomas are very rare and arise from primitive pluripotent mesenchymal cells. They are often misdiagnosed as pulmonary thromboembolism, leading to futile anticoagulation treatment and delayed diagnosis. We present a case of a patient who showed nonspecific pulmonary symptoms and characteristic imaging manifestation. Progressive symptoms and additional imaging led to the suspicion of a pulmonary artery intimal sarcoma, which was finally confirmed by pathological biopsy. This case serves as a reminder to consider pulmonary artery intimal sarcomas in the differential diagnosis of patients with dyspnea and filling defects on computed tomography pulmonary angiography or contrast-enhanced computed tomography.

Primary cardiac undifferentiated pleomorphic sarcoma is associated with TP53 mutation during lack of MDM2 amplification, and targeted sequencing analysis reveals potentially actionable targets

Cardiac undifferentiated pleomorphic sarcoma (UPS) is a rare malignancy. Several studies have revealed frequent MDM2, CDK4, PDFGRA, and KIT amplifications and CDKN2A and CDKN2B deletions. Cases lacking the above copy number alterations may harbor alternative driver mutations; however, little is known about such occurrences. This study was conducted to gain further insights into the molecular features of cardiac UPS using targeted sequencing of 560 cancer-related genes, and fluorescence in situ hybridization and immunohistochemistry of MDM2, CDK4, CDKN2A, TP53, and RB1 in 9 cardiac UPS cases. TP53 mutation or CDKN2A deletion was found in cases lacking MDM2 amplification. Further, p53 overexpression was detected in the case with TP53 mutation, while p16 expression was completely lost in the case with CDKN2A homozygous deletion. p16 overexpression was found in cases with MDM2 and CDK4 amplification but without CDKN2A deletion. Immunohistochemistry of MDM2, CDK4, p53, and p16 is expected to be preliminarily used for gene status analysis. As cardiac UPS and intimal sarcomas are merging into a single spectrum, mutation data for 3 cardiac UPS and 9 intimal sarcomas from the literature, as well as data for 5 cardiac UPS in our study were evaluated, and known recurrently mutated cancer driver genes, including PDGFRB, TP53, ALK, PTCH1, RET, ERBB4, JAK3, GATA1, PIK3CG, and RARA, were identified. Several new potentially actionable mutations, including those in RARA, ALK, PTCH1, RET, ROS1, ABL1, and MET, were also found. These findings improve the molecular understanding of this rare malignancy and are expected to provide a basis for developing precision therapeutics for cardiac UPS and intimal sarcomas.

Undifferentiated and dedifferentiated soft tissue neoplasms: Immunohistochemical surrogates for differential diagnosis

Undifferentiated soft tissue sarcomas (USTS) are described in the current World Health Organization Classification of Soft Tissue and Bone Tumours as those showing no identifiable line of differentiation when analyzed by presently available technologies. This is a markedly heterogeneous group, and the diagnosis of USTS remains one of exclusion. USTS can be divided into four morphologic subgroups: pleomorphic, spindle cell, round cell and epithelioid undifferentiated sarcomas, with this combined group accounting for up to 20% of all soft tissue sarcomas. As molecular advances enable the stratification of emerging genetic subsets within USTS, particularly within undifferentiated round cell sarcomas, other groups, particularly the category of undifferentiated pleomorphic sarcomas (UPS), still remain difficult to substratify and represent heterogeneous collections of neoplasms often representing the common morphologic endpoints of a variety of malignant tumors of various (mesenchymal and non-mesenchymal) lineages. However, recent molecular developments have also enabled the identification and correct classification of many tumors from various lines of differentiation that would previously have been bracketed under 'UPS'. This includes pleomorphic neoplasms and dedifferentiated neoplasms (the latter typically manifesting with an undifferentiated pleomorphic morphology) of mesenchymal (e.g. solitary fibrous tumor and gastrointestinal stromal tumor) and non-mesenchymal (e.g. melanoma and carcinoma) origin. The precise categorization of 'pleomorphic' or 'undifferentiated' neoplasms is critical for prognostication, as, for example, dedifferentiated liposarcoma typically behaves less aggressively than other pleomorphic sarcomas, and for management, including the potential for targeted therapies based on underlying recurrent molecular features. In this review we focus on undifferentiated and dedifferentiated pleomorphic and spindle cell neoplasms, summarizing their key genetic, morphologic and immunophenotypic features in the routine diagnostic setting, and the use of immunohistochemistry in their principal differential diagnosis, and highlight new developments and entities in the group of undifferentiated and dedifferentiated soft tissue sarcomas.

Re-evaluating tumors of purported specialized prostatic stromal origin reveals molecular heterogeneity, including non-recurring gene fusions characteristic of uterine and soft tissue sarcoma subtypes

Tumors of purported specialized prostatic stromal origin comprise prostatic stromal sarcomas (PSS) and stromal tumors of uncertain malignant potential (STUMP). Prior studies have described their clinicopathologic characteristics, but the molecular features remain incompletely understood. Moreover, these neoplasms are morphologically heterogeneous and the lack of specific adjunctive markers of prostatic stromal lineage make precise definition more difficult, leading some to question whether they represent a specific tumor type. In this study, we used next-generation DNA and RNA sequencing to profile 25 primary prostatic mesenchymal neoplasms of possible specialized prostatic stromal origin, including cases originally diagnosed as PSS (11) and STUMP (14). Morphologically, the series comprised 20 cases with solid architecture (11 PSS and 9 STUMP) and 5 cases with phyllodes-like growth pattern (all STUMP). Combined DNA and RNA sequencing results demonstrated that 19/22 (86%) cases that underwent successful sequencing (either DNA or RNA) harbored pathogenic somatic variants. Except for TP53 alterations (6 cases), ATRX mutations (2 cases), and a few copy number variants (-13q, -14q, -16q and +8/8p), the findings were largely nonrecurrent. Eight gene rearrangements were found, and 4 (NAB2-STAT6, JAZF1-SUZ12, TPM3-NTRK1 and BCOR-MAML3) were useful for reclassification of the cases as specific entities. The present study shows that mesenchymal neoplasms of the prostate are morphologically and molecularly heterogeneous and include neoplasms that harbor genetic aberrations seen in specific mesenchymal tumors arising in other anatomic sites, including soft tissue and the uterus. These data suggest that tumors of purported specialized prostatic stromal origin may perhaps not represent a single diagnostic entity or specific disease group and that alternative diagnoses should be carefully considered.

Pulmonary artery intimal sarcoma - A primeval or rediscovered tumor? A report of 14 new cases with literature review

Pulmonary artery sarcomas (PAS) are rare with many being undifferentiated pleomorphic or spindle cell (UPSC) sarcomas with variable atypia. The term pulmonary artery intimal sarcoma (PAIS) was rarely coined in the early literature and sometimes used for luminal sarcomas. With the advent of immunohistochemistry and molecular genetics, many of these UPSC sarcomas were found to frequently overpress MDM2 and/or CDK4 and PDGFRA with genetic alterations in 12q12-15 and 4q12, where the MDM2, CDK4 and PDGFRA genes are located. These recent developments enabled refinement in diagnosis of PAIS. We diagnosed 14 cases of PAIS (6 males and 8 females, mean age 44 years) in 2015 - 2020 in our institution. Six were initially misdiagnosed as thromboembolism and the remaining pulmonary artery tumors. The tumors were pulmonary artery intraluminal polypoid masses with histology of spindle cell sarcomas exhibiting immunohistochemical positivity for MDM2 (100%) and CDK4 (79%) with MDM2 gene amplification (100%). Ten surgically treated patients fared better than four other biopsy only and not surgically treated patients, who died of disease within 5-11 months. PAIS needs to be differentiated from other spindle cell tumors and those exhibiting MDM2 gene amplification, especially dedifferentiated liposarcoma. The use of biopsy to provide diagnostic material poses a sampling error problem and correlation with clinical, radiologic, histologic, immunophenotypic and genotypic features are essential for accurate diagnosis and early surgical intervention of PAIS.

Primary angiosarcoma of aorta: A systematic review

PURPOSE

To elucidate the epidemiology, anatomical, presentation, classification, pathology, investigative modalities, management and prognosis of primary angiosarcoma of the aorta.

MATERIAL AND METHODS

A systematic review of literature from the database inception to January 2021 in PubMed and Embase, CINAHL and Cochrane Library in accordance to PRISMA was conducted. Retrieval and extraction was performed by two independent reviewers. The hierarchy of the evidence was assessed through the National Institute for Health and Care Excellence Checklist. Data were subjected to pooled prevalence analysis, Kaplan-Meier survival and test of probability using log-rank analysis. This review is registered with International Prospective Register of Systematic Reviews: RD42021231314.

RESULTS

82 studies with n = 123 cases met the inclusion criterion. Abdominal (45%) aorta was the commonest anatomical site with female predominance in ascending aorta (4:1) and aortic arch (2:1). The longest survival was in the ascending aorta and the shortest in the abdominal aorta [540 (interquartile range [IQR], 7-1560 days vs. 180 (IQR, 1-5730 days)], respectively. The overall median survival was 210 days (IQR, 1-5730 days) or 7 months. Lack of metastasis (47%) was a marker of longer survival (p < 0.03) irrespective of other attributes.

CONCLUSION

The pathophysiology appears to be a trend of increasing fatigue, fever and weight loss associated with segmental dysfunction of the aorta projecting occlusive or destructive phenotypes. Computed tomography angiography features of volume-occupying, bulky, polypoid (intraluminal), protrusive vegetation, hyper vascular without atherosclerotic lesions are extremely suggestive of PA of the aorta at 5th and 6th decades of life.

Aortic Angiosarcoma in Association with Endovascular Aneurysm Repair: Case Report and Review of the Literature

BACKGROUND Primary aortic sarcoma often poses diagnostic challenges for pathologists and clinicians because of a very low incidence and controversy over nomenclature and definition. We report a case of aortic angiosarcoma in association with a graft. We also conducted a clinicopathological review of cases of primary aortic sarcomas associated with implanted grafts. CASE REPORT The patient was an 82-year-old woman. She underwent thoracic endovascular aneurysm repair (TEVAR) at age 78 because of an aneurysm in the descending aorta. Approximately 4 years after the TEVAR, computed tomography revealed a type II endoleak and expansion of the aneurysm. Her c-reactive protein level rose to 34 mg/dL, and Ga scintigraphy showed 67Ga accumulation at the aneurysm. She had fever up to 39°C, and a stent graft infection was suspected. Despite administration of antibiotics, her condition deteriorated, and she died. Postmortem examination identified epithelioid aortic angiosarcoma at the aorta with aneurysm repair and the graft, and the aortic angiosarcoma invaded the left lower lobe of the lung. CONCLUSIONS Our clinicopathological review revealed that the proper clinical diagnosis was very difficult owing to confusion of aortic sarcoma after the implantation with the infected graft, atypical endoleak, or pseudoaneurysm. The histological diagnosis was ambiguous because immunohistochemical and genetic studies were not adequately conducted. Overall prognosis of aortic sarcoma is poor as most patients die within a year, with no effective treatments. It is hoped that recent projects for genomic medicine will provide useful insights about the diagnosis and treatment of these cancers.

An Unusual Cause of Functional Mitral Stenosis: A Left Atrial Intimal Sarcoma

Primary cardiac tumors are rare, with an incidence of <0.1% in postmortem series; sarcomas comprise 75% of these. Cardiac sarcomas may be life-threatening at the time of presentation. We describe a left atrial intimal sarcoma presenting with constitutional symptoms, obstructive shock, and systemic emboli, and treated with proton beam therapy. (Level of Difficulty: Intermediate.)

MDM2 Amplified Sarcomas: A Literature Review

Murine Double Minute Clone 2, located at 12q15, is an oncogene that codes for an oncoprotein of which the association with p53 was discovered 30 years ago. The most important function of MDM2 is to control p53 activity; it is in fact the best documented negative regulator of p53. Mutations of the tumor suppressor gene p53 represent the most frequent genetic change in human cancers. By overexpressing MDM2, cancer cells have another means to block p53. The sarcomas in which MDM2 amplification is a hallmark are well-differentiated liposarcoma/atypical lipomatous tumor, dedifferentiated liposarcoma, intimal sarcoma, and low-grade osteosarcoma. The purpose of this review is to summarize the typical clinical, histopathological, immunohistochemical, and genetic features of these tumors.

Pulmonary artery intimal sarcoma mimicking pulmonary thromboembolism: A case report

RATIONALE

Pulmonary artery intimal sarcoma is a rare tumor with exceptionally high mortality and easily misdiagnosed as pulmonary thromboembolism pulmonary thromboembolism (PTE) due to the nonspecific clinical presentation and symptom. Misdiagnosis or untimely diagnosis makes the disease progress to an advanced stage and eventually leads to a poor prognosis.

PATIENT CONCERNS

A 37-year-old Chinese female presented with chest tightness and dyspnea for 3 months. Echocardiography and chest computed tomography revealed an intraluminal obstruction of the pulmonary arteries. Tests of serum tumor makers showed slight elevation for carbohydrate antigen-125, and α-fetoprotein. PTE was suspected according to the radiological and laboratory findings.

DIAGNOSIS

Microscopic findings of the presumed thrombus showed prominent myxoid and edematous background with atypical spindled cells and curvilinear vascularity. Immunohistochemical staining demonstrated that the atypical spindled cells were positive for vimentin but negative for CK, S100, SMA, desmin, CD68, STAT6, CD34, β-catenin, ALK-p80, p53, and MDM2. According to the radiological and pathological findings, the diagnosis of fibrosarcoma of pulmonary artery was made.

INTERVENTIONS

The patient underwent surgical resection and the mass was excised as completely as possible.

OUTCOME

Follow-up information showed no evidence of recurrence or metastasis after 3 months postresection.

LESSONS

Because of the low incidence rate, nonspecific clinical symptoms, and radiological findings, primary fibrosarcoma of the pulmonary artery is commonly misdiagnosed as PTE. Pathological examination is necessary to confirm the diagnosis.

Candidate Biomarkers for Specific Intraoperative Near-Infrared Imaging of Soft Tissue Sarcomas: A Systematic Review

Simple Summary

Near-infrared imaging of tumors during surgery facilitates the oncologic surgeon to distinguish malignant from healthy tissue. The technique is based on fluorescent tracers binding to tumor biomarkers on malignant cells. Currently, there are no clinically available fluorescent tracers that specifically target soft tissue sarcomas. This review searched the literature to find candidate biomarkers for soft tissue sarcomas, based on clinically used therapeutic antibodies. The search revealed 7 biomarkers: TEM1, VEGFR-1, EGFR, VEGFR-2, IGF-1R, PDGFRα, and CD40. These biomarkers are abundantly present on soft tissue sarcoma tumor cells and are already being targeted with humanized monoclonal antibodies. The conjugation of these antibodies with a fluorescent dye will yield in specific tracers for image-guided surgery of soft tissue sarcomas to improve the success rates of tumor resections.

Abstract

Surgery is the mainstay of treatment for localized soft tissue sarcomas (STS). The curative treatment highly depends on complete tumor resection, as positive margins are associated with local recurrence (LR) and prognosis. However, determining the tumor margin during surgery is challenging. Real-time tumor-specific imaging can facilitate complete resection by visualizing tumor tissue during surgery. Unfortunately, STS specific tracers are presently not clinically available. In this review, STS-associated cell surface-expressed biomarkers, which are currently already clinically targeted with monoclonal antibodies for therapeutic purposes, are evaluated for their use in near-infrared fluorescence (NIRF) imaging of STS. Clinically targeted biomarkers in STS were extracted from clinical trial registers and a PubMed search was performed. Data on biomarker characteristics, sample size, percentage of biomarker-positive STS samples, pattern of biomarker expression, biomarker internalization features, and previous applications of the biomarker in imaging were extracted. The biomarkers were ranked utilizing a previously described scoring system. Eleven cell surface-expressed biomarkers were identified from which 7 were selected as potential biomarkers for NIRF imaging: TEM1, VEGFR-1, EGFR, VEGFR-2, IGF-1R, PDGFRα, and CD40. Promising biomarkers in common and aggressive STS subtypes are TEM1 for myxofibrosarcoma, TEM1, and PDGFRα for undifferentiated soft tissue sarcoma and EGFR for synovial sarcoma.

Intimal sarcomas and undifferentiated cardiac sarcomas carry mutually exclusive MDM2, MDM4, and CDK6 amplifications and share a common DNA methylation signature

Undifferentiated mesenchymal tumors arising from the inner lining (intima) of large arteries are classified as intimal sarcomas (ISA) with MDM2 amplification as their molecular hallmark. Interestingly, undifferentiated pleomorphic sarcomas (UPS) of the heart have recently been suggested to represent the cardiac analog of ISA due to morphological overlap and high prevalence of MDM2 amplifications in both neoplasms. However, little is known about ISAs and cardiac UPS without MDM2 amplifications and molecular data supporting their common classification is sparse. Here, we report a series of 35 cases comprising 25 ISAs of the pulmonary artery, one ISA of the renal artery and 9 UPS of the left atrium. Tumors were analyzed utilizing the Illumina Infinium MethylationEPIC BeadChip array, enabling copy number profile generation and unsupervised DNA methylation analysis. DNA methylation patterns were investigated using t-distributed stochastic neighbor embedding (t-SNE) analysis. Histologically, all ISAs and UPS of the left atrium resembled extra-cardiac UPS. All cases exhibited highly complex karyotypes with overlapping patterns between ISA and UPS. 29/35 cases showed mutually exclusive amplifications in the cell-cycle associated oncogenes MDM2 (25/35), MDM4 (2/35), and CDK6 (2/35). We further observed recurrent co-amplifications in PDGFRA (21/35), CDK4 (15/35), TERT (11/35), HDAC9 (9/35), and CCND1 (4/35). Sporadic co-amplifications occurred in MYC, MYCN, and MET (each 1/35). The tumor suppressor CDKN2A/B was frequently deleted (10/35). Interestingly, DNA methylation profiling (t-SNE) revealed an overlap of ISA and cardiac UPS. This "ISA" methylation signature was distinct from potential histologic and molecular mimics. In conclusion, our data reveal MDM4 and CDK6 amplifications in ISAs and UPS of the left atrium, lacking MDM2 amplification. We further report novel co-amplifications of various oncogenes, which may have therapeutic implications. Finally, the genetic and epigenetic concordance of ISAs and UPS of the left atrium further supports a shared pathogenesis and common classification.

Relationship between PDGFR expression and the response to pazopanib in intimal sarcoma of the pulmonary artery: A case report

Intimal sarcoma of the pulmonary artery (PAIS) is a rare disease with a poor prognosis. Pazopanib, which has been indicated in metastatic non-adipocytic soft-tissue sarcomas and is expected to be active in PAIS, is a multi-kinase inhibitor that targets the tyrosine kinase activity of vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR) and stem cell factor receptor. The present study reports findings related to two cases of PAIS with PDGF and VEGF expression following treatment with pazopanib. A case with a moderate to strong expression of PDGFR-α and -β presented a long-term stable disease when treated with pazopanib (progression-free survival, 5.8 months). In a second case with a weak expression of PDGFR-α and -β, the disease progressed rapidly on pazopanib (progression-free survival, 1.1 months). VEGFR-2 was not expressed in the tumors of both cases. The level of PDGFR expression in the tumor tissue may therefore be predictive of pazopanib efficacy.

Genetic aberrations and molecular biology of cardiac sarcoma

Cardiac tumors are rare and complex entities. Early assessment and differentiation between non-neoplastic and neoplastic masses, be they benign or malignant, is essential for guiding diagnosis, determining prognosis, and planning therapy. Cardiac sarcomas represent the most frequent primary malignant histotype. They could have manifold presentations so that the diagnosis is often belated. Moreover, considering their rarity and the limitation due to the cardiac location itself, the optimal multimodal management of patients affected by primary cardiac sarcomas still remains highly difficult and outcome dismal. Therefore, there is an urgent need to improve these results mainly focusing on more adequate tools for prompt diagnosis and exploring new and more effective therapies. Knowledge about the molecular landscape and pathogenesis of cardiac sarcoma is even more limited due to the rarity of this disease. In this sense, the molecular characterization of heart tumors could unfold potentially novel, druggable targets. In this review, we focused on genetic aberrations and molecular biology of cardiac sarcomas, collecting the scarce information available and resuming all the molecular findings discovered in each tumor subtype, with the aim to get further insights on mechanisms involved in tumor growth and to possibly highlight specific molecular profiles that can be used as diagnostic tests and unveil new clinically actionable targets in this tricky and challenging disease.

A comprehensive review on the diagnosis and management of intimal sarcoma of the pulmonary artery

Only a few hundred cases of intimal sarcomas of pulmonary artery (ISPA) were reported on the literature. Diagnosis of this rare entity is a challenging dilemma with the need for a high expertise in the radiological and pathological identification of ISPA. Treatment strategies rely initially on an early aggressive surgery aiming for complete surgical resection with clear margins while no clear recommendations guiding the choice for additional drug therapy or radiotherapy exist. In this article, we perform an extensive review of the literature on ISPA with details on the clinical presentation, diagnosis and management strategies. An additional goal of this paper is to make practicing oncologists aware of this rare entity with clear idea on the initial management.

Kaposi's sarcoma-associated herpesvirus viral protein kinase phosphorylates extracellular signal-regulated kinase and activates MAPK/ERK signaling pathway

Open reading frame 36 (ORF36) of Kaposi's sarcoma-associated herpesvirus (KSHV) encodes a serine/threonine-type viral protein kinase (vPK). Previous studies have examined the functions of KSHV vPK; however, its role in the activation of extracellular signal-regulated kinase (ERK1/2) has not yet been described to date. Using HEK 293 cell lines, we performed a human phospho-kinase array analysis to screen for MAPK signaling pathways kinases that are activated by KSHV vPK. In addition, we investigated the regulator protein phosphorylation of up/downstream ERK1/2 pathway; nuclear translocation of phosphorylated ERK1/2; and regulation of transcription factor, inflammatory cytokine, and pro-/anti-apoptotic factor by KSHV vPK transfection. Here, we demonstrated that KSHV vPK activates ERK1/2 signaling pathway and plays an important role in the activation of MAPK/ERK signaling pathway.

Pulmonary intimal sarcoma involving the pulmonary valve and right ventricular outflow tract: A case report and literature review

INTRODUCTION

Pulmonary artery intimal sarcoma (PAIS) is a rare and highly aggressive tumor, and approximately 80% of pulmonary cases occur in the pulmonary trunk. We report herein a case of retrograde extension of the sarcoma to the pulmonary valve and right ventricle, which is an uncommon manifestation of this lethal tumor.

PATIENT CONCERNS

A 41-year-old woman was initially diagnosed with pulmonary thromboembolism (PTE) and transferred to our hospital.

DIAGNOSIS

Computed tomographic pulmonary angiography (CTPA) showed that there are low-density filling defects in both pulmonary arteries, and the patient was diagnosed with PTE. However, the ultrasonographers considered that the lesion is a space-occupying type that involves the right ventricular outflow tract and pulmonary valve instead of PTE. Postoperative pathology confirmed the diagnosis of PAIS.

INTERVENTIONS

The patient underwent resection of pulmonary artery sarcoma and endarterectomy.

OUTCOMES

During the follow-up via telephone 1 month after discharge, the patient reported to have been feeling well.

CONCLUSION

Owing to the rarity of the disease and its non-specific clinical manifestations, approximately half of the PAIS cases are misdiagnosed or have a delayed diagnosis. Thus, improving our understanding of the disease and facilitating its early diagnosis are essential.

Intimal sarcoma of the left atrium presenting with transient ischaemic attack - A case report and review of the literature

A 31-year-old female with a history of polycystic ovary syndrome and two recent miscarriages presented with symptoms of a transient ischemic attack. Echocardiography to assess for possible embolic source identified a 4.8 cm left atrial mass, presumed to be an atrial myxoma. At surgery the tumor was suspicious of malignancy. Histopathology revealed a heterogeneous hyper- and hypo-cellular spindle cell tumor showing mild atypia. Atrial myxoma markers were negative. The Ki67 proliferation factor was 30% and fluorescence in situ hybridization (FISH) analysis showed MDM2 amplification. Expert review confirmed the morphological, immunohistochemical, and FISH features to be of a cardiac intimal sarcoma. Recent improvements in imaging, surgery, and molecular testing have increased diagnoses of primary cardiac intimal sarcomas. Here we discuss the pathological and clinical implications of these rare atrial myxoma mimics. <Learning objective: Intimal sarcomas are rare, aggressive tumors typically associated with great vessels, however, molecular diagnoses of cardiac intimal sarcomas are increasing. Presentation is varied. Cardiac symptoms and emboli in young patients should prompt investigation with high levels of suspicion. Intimal sarcomas show MDM2 amplification with genetic aberration. Careful pre-operative planning to achieve clear surgical margins almost doubles life expectancy. Chemoradiotherapy may be beneficial. MDM2 and PDGFRa inhibitors are in development.>.

Phospho-Protein Arrays as Effective Tools for Screening Possible Targets for Kinase Inhibitors and Their Use in Precision Pediatric Oncology

The specific targeting of signal transduction by low-molecular-weight inhibitors or monoclonal antibodies represents a very promising personalized treatment strategy in pediatric oncology. In this study, we present the successful and clinically relevant use of commercially available phospho-protein arrays for analyses of the phosphorylation profiles of a broad spectrum of receptor tyrosine kinases and their downstream signaling proteins in tumor tissue samples. Although these arrays were made for research purposes on human biological samples, they have already been used by several authors to profile various tumor types. Our study performed a systematic analysis of the advantages and pitfalls of the use of this method for personalized clinical medicine. In certain clinical cases and their series, we demonstrated the important aspects of data processing and evaluation, the use of phospho-protein arrays for single sample and serial sample analyses, and the validation of obtained results by immunohistochemistry, as well as the possibilities of this method for the hierarchical clustering of pediatric solid tumors. Our results clearly show that phospho-protein arrays are apparently useful for the clinical consideration of druggable molecular targets within a specific tumor. Thus, their potential validation for diagnostic purposes may substantially improve the personalized approach in the treatment of relapsed or refractory solid tumors.

Whole-exome sequencing insights into pulmonary artery sarcoma mimicking pulmonary embolism: a case report and review

Pulmonary artery sarcoma (PAS) is a rare and aggressive mesenchymal tumor that often mimics thromboembolic disease. Due to its rare and fatal nature, patients are often underdiagnosed or misdiagnosed. There is still no consensus regarding the diagnosis and treatment of PAS. We present a case of a 63 year old male misdiagnosed with pulmonary thromboembolism who received anticoagulant therapy. ¹⁸FDG positron emission tomography (PET) integrated with computed tomography (PET/CT) and subsequent surgery led to the final diagnosis of PAS. Whole exome sequencing of the tissue identified the genetic alterations profile of PAS: copy number variation (CNV) of KIT and mutations of TP53, PIK3CA, IL7R and ATR. Treated with chemotherapy followed by anlotinib, the patient's survival time was 8 months after firm diagnosis. To our knowledge, anlotinib used as a treatment for PAS has not been reported.

Unique Aberrations in Intimal Sarcoma Identified by Next-Generation Sequencing as Potential Therapy Targets

Intimal sarcomas are rare and histologically heterogeneous tumors, commonly arising from the pulmonary arteries. They have remained challenging to treat. Few studies in the literature study the genomics of this cancer. Identifying targetable alterations is an important step in advancing the treatment of intimal sarcomas. Using data from the American Association for Cancer Research Project Genomics Evidence Neoplasia Information Exchange (AACR GENIE) database, we cataloged genetic alterations and assessed their clinical utility from thirteen patients with intimal sarcoma. Notable copy number alterations included amplification in MDM2, CDK4, PDGFRA, and NOTCH2, as well as copy number losses in CDKN2A and CDKN2B. Actionable alterations included mutations in ATM/ATR, PTCH1, and PDGFRB. Moreover, genomic rearrangement events, specifically PDE4DIP-NOTCH2 and MRPS30-ARID2 fusions were identified. Co-occurring alterations included a NOTCH2 copy number gain in the PDE4DIP-NOTCH2 fusion positive tumor and PDGFRB mutations in both fusion-positive cases. Our study suggests that PDGFRB may be relevant in the tumorigenesis process. Including genomic profiling in the management of intimal sarcoma and potential enrollment in targeted therapy trials is warranted.

Activity and safety of crizotinib in patients with alveolar soft part sarcoma with rearrangement of TFE3: European Organization for Research and Treatment of Cancer (EORTC) phase II trial 90101 'CREATE'

Background

Alveolar soft part sarcoma (ASPS) is an orphan malignancy associated with a rearrangement of transcription factor E3 (TFE3), leading to abnormal MET gene expression. We prospectively assessed the efficacy and safety of the MET tyrosine kinase inhibitor crizotinib in patients with advanced or metastatic ASPS.

Patients and methods

Eligible patients with reference pathology-confirmed ASPS received oral crizotinib 250 mg bd. By assessing the presence or absence of a TFE3 rearrangement, patients were attributed to MET+ and MET- sub-cohorts. The primary end point was the objective response rate (ORR) according to local investigator. Secondary end points included duration of response, disease control rate (DCR), progression-free survival (PFS), progression-free rate, overall survival (OS) and safety.

Results

Among 53 consenting patients, all had a centrally confirmed ASPS and 48 were treated. A total of 45 were eligible, treated and assessable. Among 40 MET+ patients, 1 achieved a confirmed partial response (PR) that lasted 215 days and 35 had stable disease (SD) as best response (ORR: 2.5%, 95% CI 0.6% to 80.6%). Further efficacy end points in MET+ cases were DCR: 90.0% (95% CI 76.3% to 97.2%), 1-year PFS rate: 37.5% (95% CI 22.9% to 52.1%) and 1-year OS rate: 97.4% (95% CI 82.8% to 99.6%). Among 4 MET- patients, 1 achieved a PR that lasted 801 days and 3 had SD (ORR: 25.0%, 95% CI 0.6% to 80.6%) for a DCR of 100% (95% CI 39.8% to 100.0%). The 1-year PFS rate in MET- cases was 50% (95% CI 5.8% to 84.5%) and the 1-year OS rate was 75% (95% CI 12.8% to 96.1%). One patient with unknown MET status due to technical failure achieved SD but stopped treatment due to progression after 17 cycles. The most common crizotinib-related adverse events were nausea [34/48 (70.8%)], vomiting [22/48 (45.8%)], blurred vision [22/48 (45.8%)], diarrhoea (20/48 (41.7%)] and fatigue [19/48 (39.6%)].

Conclusion

According to European Organization for Research and Treatment of Cancer (EORTC) efficacy criteria for soft tissue sarcoma, our study demonstrated that crizotinib has activity in TFE3 rearranged ASPS MET+ patients.

Clinical trial number

EORTC 90101, NCT01524926.

Characterization of pulmonary intimal sarcoma cells isolated from a surgical specimen: In vitro and in vivo study

Pulmonary intimal sarcoma (PIS) constitutes a rare sarcoma originating from the intimal cells of pulmonary arteries. The pathogenesis of PIS remains to be elucidated and specific treatments have not been established; therefore, prognosis is generally poor. The purpose of our study was to isolate and characterize PIS cells from a specimen resected from a patient with PIS. The surgical specimen was minced and incubated, and spindle-shaped and small cells were successfully isolated and designated as PIS-1. PIS-1 cells at passages 8–9 were used for all in vitro and in vivo experiments. Immunocytochemistry showed that PIS-1 cells were positive for vimentin, murine double minute 2, and CD44 and negative for α-smooth muscle actin, CD31, von Willebrand factor, and desmin. PIS-1 cells exhibited the hallmarks of malignant cells including the potential for autonomous proliferation, anchorage-independent growth, invasion, genetic instability, and tumorigenicity in severe combined immunodeficiency mice. The PIS-1 cells highly expressed tyrosine kinase receptors such as platelet-derived growth factor receptor, and vascular endothelial growth factor receptor 2. Pazopanib, a multi-targeted tyrosine kinase inhibitor, suppressed the proliferation of PIS-1 cells in vitro and the growth of tumors formed from xenografted PIS-1 cells. A PIS cell line was thus successfully established. The PIS-1 cells highly expressed tyrosine kinase receptors, which may be a target for treatment of PIS.

Mesenchymal tumors of the lung: diagnostic pathology, molecular pathogenesis, and identified biomarkers

Lung cancers are mainly composed of epithelial tumors such as carcinomas. Since mesenchymal tumors that arise in the lung are very rare, they have garnered little attention. The 2015 World Health Organization (WHO) classification of lung tumors has undergone revision, not only for carcinomas but also for mesenchymal tumors. The current version now includes PEComatous tumors, myoepithelial tumors, and pulmonary myxoid sarcomas with EWSR1-CREB1 translocation as new disease entities. To date, no review article has comprehensively summarized what is known about pulmonary mesenchymal tumors in accordance with the latest WHO classification. In this review, we attempt to summarize the data about these tumors in line with the 2015 WHO classification (except for pediatric tumors), focusing on their diagnostic pathology, molecular pathogenesis, and identified biomarkers for differential diagnoses. We also address the recently recognized pulmonary mesenchymal tumors that have not yet been included in the WHO classification. An increased understanding of the molecular characteristics of pulmonary mesenchymal tumors has the potential to provide clinicians with the best therapeutic options for patients with these tumors.

Primary cardiac sarcomas: A multi-national retrospective review

BACKGROUND

Primary cardiac sarcoma (PCS) is a rare but often fatal disease. The current study aimed to analyze the impact of baseline demographics, local and systemic therapies in a contemporary cohort.

METHODS

Clinical records of PCS across six institutions in three continents were reviewed. Kaplan-Meier method was used to estimate survival. Cox proportional hazard model was used to determine variables impacting progression-free survival (PFS) or overall survival (OS).

RESULTS

Sixty-one patients with PCS (1996-2016) were identified. The median age at diagnosis was 46 (range 18-79); 36% (n = 22) presented with metastatic disease. The most common histology was angiosarcoma (n = 24, 39%). A total of 46 patients received surgery (75%) but only 5 (8%) patients achieved R0 resection. Multi-modality treatment to the primary tumor was given to 28 patients (46%; localized disease 23/39 (59%); metastatic disease 5/22 (23%)). The median OS for the entire cohort was 17.5 months (95% CI 9.5-20.6), with seven (11%) patients surviving longer than 36 months. On multi-variate analysis, age <65 (P = 0.01) was the only significant favorable prognostic factor. For first-line palliative chemotherapy, the median PFS was 4.4 months (95% CI 2.9-7.7 months). The best response for first-line chemotherapy was 32% (CR = 1, PR = 9). No significant improvement in OS was identified in patients presenting throughout the 20-year period of this review.

CONCLUSION

Younger age at diagnosis was associated with improved outcome although the prognosis of PCS remains poor. Given the lack of improvement in survival, further dedicated research is required.

A Case of Undifferentiated Sarcoma in the Superior Vena Cava and Bilateral Cervical Veins

BACKGROUND 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. CASE REPORT The patient was a 76 years-old Japanese man who presented with superior vena cava (SVC) syndrome. CT identified a tumor or thrombi in the SVC, bilateral brachiocephalic, and jugular veins. The histology of the biopsy specimen revealed an undifferentiated tumor without immunohistochemical positivity for all antibodies available except vimentin and smooth muscle actin. He was treated conservatively and died of respiratory failure 2 months after presentation. At autopsy, the large veins were filled by a sausage-like tumor and the cut sections revealed hemorrhagic and necrotic tumor. The tumor cells were negative with MDM2, CDK4, and PDGFRA by immunohistochemistry. Amplification of MDM2 and PDGFRA was not identified by fluorescence in-situ hybridization. CONCLUSIONS We concluded that the case was an undifferentiated sarcoma (IS without any specific phenotype) arising in the SVC, bilateral brachiocephalic, and jugular veins. We propose a way of subtyping sarcomas with predominantly intraluminal growth in large vessels and the heart based on immunohistochemistry and amplification of MDM2 and PDGFRA. However, proper subtyping of these sarcomas requires further study.

Involvement of platelet-derived growth factor ligands and receptors in tumorigenesis

Platelet-derived growth factor (PDGF) isoforms and their receptors have important roles during embryogenesis, particularly in the development of various mesenchymal cell types in different organs. In the adult, PDGF stimulates wound healing and regulates tissue homeostasis. However, overactivity of PDGF signalling is associated with malignancies and other diseases characterized by excessive cell proliferation, such as fibrotic conditions and atherosclerosis. In certain tumours, genetic or epigenetic alterations of the genes for PDGF ligands and receptors drive tumour cell proliferation and survival. Examples include the rare skin tumour dermatofibrosarcoma protuberance, which is driven by autocrine PDGF stimulation due to translocation of a PDGF gene, and certain gastrointestinal stromal tumours and leukaemias, which are driven by constitute activation of PDGF receptors due to point mutations and formation of fusion proteins of the receptors, respectively. Moreover, PDGF stimulates cells in tumour stroma and promotes angiogenesis as well as the development of cancer-associated fibroblasts, both of which promote tumour progression. Inhibitors of PDGF signalling may thus be of clinical usefulness in the treatment of certain tumours.

Dasatinib

Dasatinib is an oral available short-acting inhibitor of multiple tyrosine kinases. It was designed to inhibit ABL and SRC, but also has activity in multiple other kinases, including c-KIT, PDGFR-α, PDGFR-β, and ephrin receptor kinases. Dasatinib is a very potent inhibitor of BCR-ABL and an effective treatment for the BCR-ABL-driven diseases chronic myeloid leukemia (CML) and Philadelphia-chromosome-positive acute lymphoblastic leukemia (Ph+ ALL), characterized by the constitutively active tyrosine kinase, BCR-ABL. Dasatinib is approved for the treatment of CML (all phases) including children and for the treatment of Ph+ ALL, resistant or intolerant to prior imatinib treatment. Randomized trials in CML comparing dasatinib with imatinib show that first-line dasatinib causes significantly deeper and faster molecular remissions. In accelerated and blastic phase CML, as well as in Ph+ ALL, dasatinib frequently induces complete hematologic and cytogenetic remissions even in imatinib pretreated patients. Remissions however are often short. Dasatinib is administered independent of food intake as a once-daily dose of 100 mg in chronic phase CML and 140 mg in Ph+ ALL or blastic phase. Side effects of dasatinib are frequent but mostly moderate and manageable and include cytopenias and pleural effusions. The review presents the preclinical and clinical activity of dasatinib with a focus on clinical studies in CML.

Activating mutation of PDGFRB gene in a rare cardiac undifferentiated intimal sarcoma of the left atrium: a case report

Cardiac sarcoma is a rare malignant tumor with undefined genetic mutations and no targeted therapy. Here in one rare case of undifferentiated cardiac intimal sarcoma (IS), a next-generation sequencing based assay, MSK-IMPACT (Memorial Sloan Kettering - Integrated Mutation Profiling of Actionable Cancer Targets), identified a somatic, activating mutation in PDGFRB, along with amplification of PDGFRA. This E472D mutation of PDGFRB was discovered for the first time in IS. These findings suggest that concurrent aberrant PDGFRA and PDGFRB signaling may be a diagnostic biomarker and molecular therapeutic target of IS of the heart.

[Not Available]

Zusammenfassung. Wir stellen den Fall einer 52-jährigen Frau vor, die initial mit Husten und leichten Brustschmerzen in der Hausarztpraxis vorstellig wurde. Bei stetiger Progression der Beschwerden wurde eine CT-Thorax durchgeführt, wobei eine ausgedehnte Lungenembolie festgestellt wurde. Nach Beginn einer oralen Antikoagulation zeigte sich keine Besserung der Beschwerden. Durch weiterführende Diagnostik mit MRI und PET-CT wurde schliesslich der Verdacht auf ein Pulmonalissarkom gestellt. Es erfolgte die operative Entfernung mittels pulmonaler Tumor-Endarteriektomie. In der Histologie zeigte sich ein R1-Resektat eines intimalen Sarkoms, weshalb zusätzlich eine additive Chemotherapie durchgeführt wurde. Trotz multimodaler Therapie und anfänglich erfreulichen klinischen Verlaufskontrollen kam es im weiteren Verlauf zur Krankheitsprogredienz, sodass weitere Metastasektomien pulmonal sowie auch im Grosshirn frontal und temporal folgten. Zudem wurde eine Radiotherapie des Ganzhirns durchgeführt. 31 Monate nach Diagnosestellung lebt die Patientin noch.

EGFR and PDGFRA co-expression and heterodimerization in glioblastoma tumor sphere lines

Concurrent amplifications of EGFR and PDGFRA have been reported in up to 5% of glioblastoma (GBM) and it remains unclear why such independent amplification events, and associated receptor overexpression, would be adaptive during glioma evolution. Here, we document that EGFR and PDGFRA protein co-expression occurs in 37% of GBM. There is wide cell-to-cell variation in the expressions of these receptor tyrosine kinases (RTKs) in stable tumor sphere lines, frequently defining tumor cell subpopulations with distinct sensitivities to growth factors and RTK inhibitors. We also find evidence for functional transactivation of PDGFRA by EGFR and EGF-induced receptor heterodimerization, both of which are abolished by EGFR inhibitors. These results indicate that GBM growth responses to targeted therapies previously tested in clinical trials are strongly influenced by the balance of EGFR and PDGFRA activation in individual cells, which is heterogeneous at baseline.

Clinicopathological features of bi-ventricular cardiac intimal sarcoma-Report of an autopsy case

We present the clinicopathological characteristics of primary cardiac intimal sarcoma which was widely spread throughout bi-ventricles. The patient had a wide range of clinical manifestations starting with left-sided heart failure then finally developing refractory right-sided heart failure during 44 months of follow-up. <Learning objective: The present clinicopathological characteristics with a wide spectrum of clinical features may provide a pivotal insight into understanding primary cardiac intimal sarcoma.>.

Macrophage infiltration and genetic landscape of undifferentiated uterine sarcomas

Endometrial stromal tumors include translocation-associated low- and high-grade endometrial stromal sarcomas (ESS) and highly malignant undifferentiated uterine sarcomas (UUS). UUS is considered a poorly defined group of aggressive tumors and is often seen as a diagnosis of exclusion after ESS and leiomyosarcoma (LMS) have been ruled out. We performed a comprehensive analysis of gene expression, copy number variation, point mutations, and immune cell infiltrates in the largest series to date of all major types of uterine sarcomas to shed light on the biology of UUS and to identify potential novel therapeutic targets. We show that UUS tumors have a distinct molecular profile from LMS and ESS. Gene expression and immunohistochemical analyses revealed the presence of high numbers of tumor-associated macrophages (TAMs) in UUS, which makes UUS patients suitable candidates for therapies targeting TAMs. Our results show a high genomic instability of UUS and downregulation of several TP53-mediated tumor suppressor genes, such as NDN, CDH11, and NDRG4. Moreover, we demonstrate that UUS carry somatic mutations in several oncogenes and tumor suppressor genes implicated in RAS/PI3K/AKT/mTOR, ERBB3, and Hedgehog signaling.

Phospholipase C gamma 1 (PLCG1) R707Q mutation is counterselected under targeted therapy in a patient with hepatic angiosarcoma

Hepatic angiosarcoma is a rare and aggressive vascular neoplasm. Pathogenic driver mutations are largely unknown. We present the case of a patient with recurrent hepatic angiosarcoma, who initially showed good response to sunitinib, followed by progression. Using comprehensive molecular techniques, we explored the potential mechanisms of resistance. By low-read-depth whole-genome sequencing, the comparison of copy number aberrations (CNAs) of the primary tumor to the skin metastatic lesion that developed after progression on sunitinib, revealed high-level amplification of the 4q11-q13.1 region (containing KIT, PDGFRA and VEGFR2 genes) that was sustained in both lesions. Whole exome sequencing on the germline, primary and metastatic tumor DNAs, resulted in 27 confirmed mutations, 19 of which (including TP53 mutation) presented in both primary and metastatic lesions. One mutation, ZNF331 frameshift deletion, was detected only in the primary tumor. In contrast, seven other mutations, including phospholipase C-gamma1 (PLCG1) R707Q mutation, were found only in the metastatic tumor, indicating selection of cells with the resistant genotype under sunitinib pressure. Our study supports the notion that PLCG1-R707Q mutation may confer VEGFR2-independent signaling and may thus cause resistance against VEGF(R)-directed therapies. This case illustrates also the advantages of using next-generation technologies in identifying individualized targeted therapy.

Case report: rapid and durable response to PDGFR targeted therapy in a child with refractory multiple infantile myofibromatosis and a heterozygous germline mutation of the PDGFRB gene

Background

Infantile myofibromatosis belongs to a family of soft tissue tumors. The majority of these tumors have benign behavior but resistant and malignant courses are known, namely in tumors with visceral involvement. The standard of care is surgical resection. Observations suggest that low dose chemotherapy is beneficial. The treatment of resistant or relapsed patients with multifocal disease remains challenging. Patients that harbor an actionable mutation in the kinase domain are potential subjects for targeted tyrosine kinase inhibitor therapy.

Case presentation

An infant boy with inborn generalized infantile myofibromatosis that included bone, intracranial, soft tissue and visceral involvement was treated according to recent recommendations with low dose chemotherapy. The presence of a partial but temporary response led to a second line of treatment with six cycles of chemotherapy, which achieved a partial response again but was followed by severe toxicity. The generalized progression of the disease was observed later. Genetic analyses were performed and revealed a PDGFRB gene c.1681C>A missense heterozygous germline mutation, high PDGFRβ phosphokinase activity within the tumor and the heterozygous germline Slavic Nijmegen breakage syndrome 657del5 mutation in the NBN gene. Targeted treatment with sunitinib, the PDGFRβ inhibitor, plus low dose vinblastine led to an unexpected and durable response without toxicities or limitations to daily life activities. The presence of the Slavic NBN gene mutation limited standard chemotherapy dosing due to severe toxicities. Sister of the patient suffred from skull base tumor with same genotype and histology. The same targeted therapy led to similar quick and durable response.

Conclusion

Progressive and resistant incurable infantile myofibromatosis can be successfully treated with the new approach described herein. Detailed insights into the biology of the patient’s tumor and genome are necessary to understand the mechanisms of activity of less toxic and effective drugs except for up to date population-based chemotherapy regimens.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3115-x) contains supplementary material, which is available to authorized users.

PDGFRa amplification in multiple skin lesions of undifferentiated pleomorphic sarcoma: A clue for intimal sarcoma metastases

A 62-year-old human immunodeficiency virus-positive man was admitted for multiple cutaneous and subcutaneous nodules on his lower limbs, corresponding to an undifferentiated proliferation of spindle and pleomorphic cells, with irregular nuclei and numerous mitoses. The tumor cells were negative for a large panel of immunohistochemical markers, except CD10. MDM2 immunohistochemical staining was also negative, leading to the diagnosis of Fédération Nationale des Centres de Lutte contre le Cancer grade III undifferentiated pleomorphic sarcoma (UPS). Array-comparative genomic hybridization showed a highly complex karyotype, with amplification of the 4q12 region, an area that contains only the platelet-derived growth factor receptor α (PDGFRa) gene. This amplification of PDFGRa, molecular hallmark of intimal sarcoma (IS), led to the diagnosis of skin IS metastasis. A positron emission tomography showed a hypermetabolic mass protruding in the preaortic area, consistent with the diagnosis of aortic IS. Our study shows that a rare differential diagnosis in peripheral UPS can be IS skin metastasis, and underlines the importance of molecular analyses in UPS.

Pulmonary Artery Sarcoma Overexpressing Platelet-derived Growth Factor Receptor α

Pulmonary artery sarcoma is highly malignant and easily metastasizes to the systemic organs. Both the introduction of novel diagnostic procedures and the development of new treatment modalities are required to achieve long-term survival. Several studies have shown that platelet-derived growth factor receptor α (PDGFRα) gene amplification is frequently observed in pulmonary artery sarcoma. PDGFRα is known to be involved in cell proliferation in certain malignancies. PDGFRα may become a potential biological marker in pulmonary artery sarcoma. We report a case in which a diagnosis of pulmonary artery sarcoma overexpressing PDGFRα was made using endovascular catheter biopsy following positron emission tomography with integrated computed tomography (PET/CT) scans.

Surgical resection of two independent primary intimal sarcomas in the left atrium

Primary intimal sarcoma of the heart is an extremely rare tumor that is known to have a very poor prognosis. We present a case of a 65-year-old man who suffered from deteriorating congestive heart failure due to a severe mitral stenosis caused by a large mobile left atrial tumor. The patient underwent an emergency operation of the tumor in the left atrium. The tumor was attached to the inferior wall of the left atrium. After the resection of the tumor, a second tumor on the interatrial septum, which had not been detected in the preoperative investigation, was discovered and resected. The patient developed acute respiratory failure soon after the operation and succumbed to his illness. The appearance of the main tumor was cauliflower-like, which strongly suggested the possibility of malignancy. Immunohistochemistry revealed that the neoplastic cells were positive for vimentin, desmin, p16, and especially murine double minute 2 (MDM-2). The first tumor was CD34 positive and cdk4 negative, but the second tumor was more anaplastic and CD34 negative and cdk4 positive, which suggests a different origin of the two tumors. The two tumors were diagnosed as intimal sarcomas by MDM-2, which is currently considered a conclusive marker. This is an exceptionally rare case of two simultaneous and possibly independent primary intimal sarcomas in the left atrium.

Anesthetic Management for Resection of Bilateral Pulmonary Artery Sarcoma

We describe a patient who presented with a bilateral pulmonary artery sarcoma, initially treated as pulmonary embolism, that necessitated concomitant pulmonary endarterectomy and pneumonectomy. We reviewed the anesthetic management used for this procedure, which bears many similarities to the management of patients undergoing pulmonary thromboendarterectomy. Right ventricular failure, pulmonary hemorrhage, and cerebral ischemia due to circulatory arrest are life-threatening perioperative complications. The anesthesiologist can play a key role in the prevention (or timely recognition and treatment) of these perioperative complications by establishing adequate hemodynamic, echocardiographic, and neurologic monitoring and by optimizing cardiopulmonary function and coagulation.