Vascular tumors of bone: A study of 17 cases other than ordinary hemangioma, with an evaluation of the relationship of hemangioendothelioma of bone to epithelioid hemangioma, epithelioid hemangioendothelioma, and high-grade angiosarcoma

Neurosurgical Management of Spinal Epithelioid Hemangioendothelioma: Systematic Review and Illustrative Case Presentation

BACKGROUND

Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor predominantly arising in soft tissue. We report a rare case of thoracic spinal EHE with pulmonary metastasis.

METHODS

Case report and systematic review of spinal EHE.

RESULTS

A 36-year-old man presented with bilateral lower extremity weakness, progressive paresthesia, and urinary incontinence. He underwent open surgical resection of the tumor and decompression of the spinal cord, with subsequent improvement in neurologic function. Systematic review identified 84 cases of spinal EHE, 73 of which were primary, and 14 of which developed extra-spinal metastases.

CONCLUSION

EHE is an exceedingly rare tumor that may present with a wide swath of clinical symptoms. At present, no guidelines or formal treatment recommendations have been established. Surgical debulking has demonstrated efficacy as a front-line treatment, particularly in the setting of compressive neurologic dysfunction; data regarding adjuvant chemoradiation are less consistently reported, mandating further study.

Vascular Neoplasms With NFATC1/C2 Gene Alterations : Expanding the Clinicopathologic and Molecular Characteristics of a Distinct Entity

Despite significant advances in their molecular pathogenesis, skeletal vascular tumors remain diagnostically challenging due to their aggressive radiologic appearance and significant morphologic overlap. Within the epithelioid category and at the benign end of the spectrum, recurrent FOS/FOSB fusions have defined most epithelioid hemangiomas, distinguishing them from epithelioid hemangioendothelioma and angiosarcoma. More recently, the presence of EWSR1/FUS :: NFATC1/2 fusions emerged as the genetic hallmark of a novel group of unusual vascular proliferations, often displaying epithelioid morphology, with alternating vasoformative and solid growth, variable atypia, reminiscent of composite hemangioendothelioma. In this study, we further our understanding and morphologic spectrum of NFATC -fusion positive vascular neoplasms by describing 9 new cases, including soft tissue locations and novel fusion partners. Combining with the initial cohort of 5 cases, a total of 14 patients were analyzed, showing slight female predilection and an age range of 10 to 66 (mean 42 y). Twelve patients had solitary lesions, while 2 had multifocal polyostotic (pelvic bones) disease. Overall, 12 lesions were intra-osseous and 2 in soft tissue. By targeted RNA Fusion panels or FISH, there were 6 cases of EWSR1::NFATC1 , 4 EWSR1::NFATC2 , 2 FUS::NFATC2 , 1 EWSR1 rearrangement, and 1 with a novel FABP4::NFATC2 fusion. Follow-up was available in 4 patients. One patient experienced 2 local recurrences, 11 and 15 years postdiagnosis, and one patient experienced progressive disease despite multimodality treatment (curettings, embolization, radiation) over 3 years. In summary, our extended investigation confirms that NFATC -related fusions define a distinct group of vascular neoplasms with variable architecture, epithelioid phenotype, and cytologic atypia, commonly located in the bone, occasionally multifocal and with potential for local recurrence and aggressive behavior but no metastatic potential. Molecular analysis is recommended in diagnostically challenging cases with atypical histology to exclude malignancy.

Spinal Cord Syndrome Due to Extramedullary Epithelioid Hemangioendothelioma of the Thoracic Spine: A Case Report and Literature Review

We report a 48-year-old male patient with spinal epithelioid hemangioendothelioma in T3 and T4 who began with symptoms of paresthesia in the lower limbs and distal weakness of the right lower limb, back pain, increased limitation in walking, urinary incontinence, and constipation. A safe maximum resection was performed, finding residual disease during the PET/CT scan, so it was decided to treat with radiotherapy, and there was a good response to this treatment. A literature review of epithelioid hemangioendothelioma of the thoracic spine was done which showed a mean age of presentation of 41 years and a male-female ratio of 1:0.53. The main symptom was pain, which was present in 100% of the patients, and wide surgery was performed in 56.8% of the patients, intralesional surgery in 31.8%, and biopsy in 11.4%. A total of 46.6% of patients received radiation therapy, and only 6.6% received chemotherapy. The patients had an average follow-up of 38 months. We recommend that extension studies such as PET/CT scans be performed after surgical resection. This can serve as a follow-up with hemangioendothelioma epithelioma patients about metastatic disease or residual disease that will guide us in giving adjuvant treatments, such as radiotherapy or chemotherapy, for better control of the disease.

Primary vascular tumors of bone: A comprehensive literature review on classification, diagnosis and treatment

Primary vascular tumors of bone are a heterogeneous group of neoplasms, ranging from benign hemangiomas to frankly malignant epithelioid hemangioendotheliomas and angiosarcomas. Over the years, their classification has been a matter of discussion, due to morphologic similarities and uncertainty regarding biologic behavior. Over the past decade, with the development of next-generation sequencing, there has been a significant improvement in the molecular characterization of these lesions. The integration of their morphologic, immunohistochemical and molecular features has led to a better stratification, with important prognostic and therapeutic implications. Nevertheless, primary vascular bone tumors still represent a challenge for medical oncologists. Given their rarity and heterogeneity, in the last few years, there has been no significant progress in medical treatment options, so further research is needed. Here we present a review of the current knowledge regarding primary vascular tumors of the bone, correlating clinicopathologic features with tumor behavior and therapeutic approaches.

Fusion transcriptome profiling defines the monoclonal origin of multifocal epithelioid haemangioma of bone

AIMS

Epithelioid haemangioma (EH) of bone remains a highly controversial entity. Indeed, the WHO classifies EHs of soft tissues as benign tumours, whereas bone EHs are considered intermediate-locally aggressive tumours due to common multifocal presentation and local destructive growth. To gain insights into the clinical behaviour and biology of EH of bone we retrospectively analysed 42 patients treated in a single institution from 1978 to 2021.

METHODS AND RESULTS

Multifocal presentation was detected in 17 of 42 patients (40%) primarily as synchronous lesions. Patients were treated with curettage (57%), resection (29%) or biopsy, followed by radiotherapy or embolisation (14%). Follow-up (minimum 24 months) was available for 38 patients, with only five local recurrences (13%) and no death of disease. To clarify whether the synchronous bone lesions in multifocal EH represent multicentric disease or clonal dissemination, four cases were profiled by RNA-sequencing. Separate lesions from the same patient, which showed a similar transcriptional profile, expressed the same fusion transcript (involving FOS or FOSB) with identical gene breakpoints.

CONCLUSIONS

These results indicate that, in EH of bone, multifocal lesions are clonally related and therefore represent the spread of a same neoplastic clone rather than simultaneous independent tumours. This finding is in apparent contradiction with the benign clinical course of the disease, and suggests that tumour dissemination in bone EH probably reflects a phenomenon of passive spreading, with tumour cells colonising distal sites while maintaining their benign biological nature.

A Rare Case of Primary Epithelioid Hemangioma of Bone with WWTR1::FOSB Fusion: A Benign Lesion with the Potential to Mimic Malignancy

Epithelioid hemangioma of bone is a rare benign, locally aggressive vascular tumor that can be particularly challenging to diagnose given its frequent multifocality, non-specific imaging findings, and wide range of morphologic appearances. Additionally, some epithelioid hemangiomas demonstrate atypical histologic features including increased cellularity, necrosis, and moderate cytologic atypia - characteristics that may raise concern for malignancy. Molecular studies can serve as a powerful, objective tool in the differential diagnosis of diagnostically challenging epithelioid vascular tumors. Importantly, FOS and FOSB gene rearrangements have been identified as the genetic hallmarks of osseous epithelioid hemangioma, present in greater than 70% of cases. FOSB-fusion-positive epithelioid hemangioma, in particular, may display atypical histologic features. While ZFP36 is the typical FOSB fusion partner in epithelioid hemangioma, we herein present a case of epithelioid hemangioma of bone with a rare WWTR1::FOSB fusion. This case demonstrates the diagnostic challenges associated with epithelioid hemangioma, especially in the setting of FOSB gene rearrangements, and the importance of genomic studies in the work up of these vascular tumors.

The genetics of vascular tumours: an update

Recent molecular advances have shed significant light on the classification of vascular tumours. Except for haemangiomas, vascular lesions remain difficult to diagnose, owing to their rarity and overlapping clinical, radiographic and histological features across malignancies. In particular, challenges still remain in the differential diagnosis of epithelioid vascular tumours, including epithelioid haemangioma and epithelioid haemangioendothelioma at the benign/low-grade end of the spectrum, and epithelioid angiosarcoma at the high-grade end. Historically, the classification of vascular tumours has been heavily dependent on the clinical setting and histological features, as traditional immunohistochemical markers across the group have often been non-discriminatory. The increased application of next-generation sequencing in clinical practice, in particular targeted RNA sequencing (such as Archer, Illumina), has led to numerous novel discoveries, mainly recurrent gene fusions (e.g. those involving FOS, FOSB, YAP1, and WWTR1), which have resulted in refined tumour classification and improved diagnostic reproducibility for vascular tumours. However, other molecular alterations besides fusions have been discovered in vascular tumours, including somatic mutations (e.g. involving GNA family and IDH genes) in a variety of haemangiomas, as well as copy number alterations in high-grade angiosarcomas (e.g. MYC amplifications). Moreover, the translation of these novel molecular abnormalities into diagnostic ancillary markers, either fluorescence in-situ hybridisation probes or surrogate immunohistochemical markers (FOSB, CAMTA1, YAP1, and MYC), has been remarkable. This review will focus on the latest molecular discoveries covering both benign and malignant vascular tumours, and will provide practical diagnostic algorithms, highlighting frequently encountered pitfalls and challenges in the diagnosis of vascular lesions.

Vascular Tumors of Bone: Updates and Diagnostic Pitfall

Vascular tumors of bone can be diagnostically challenging because of their rarity and histologic overlap with diverse mimics. Vascular tumors of bone can be categorized as benign (hemangioma), intermediate-locally aggressive (epithelioid hemangioma), intermediate-rarely metastasizing (pseudomyogenic hemangioendothelioma), and malignant (epithelioid hemangioendothelioma and angiosarcoma). Recurrent genetic alterations have been described, such as FOSB rearrangements in pseudomyogenic hemangioendothelioma and a subset of epithelioid hemangiomas; CAMTA1 or TFE3 rearrangements in epithelioid hemangioendothelioma. This review discusses the clinical, histologic, and molecular features of vascular tumors of bone, along with diagnostic pitfalls and strategies for avoidance.

Gene fusions in vascular tumors and their underlying molecular mechanisms

INTRODUCTION

The group of vascular tumors contains many different entities, and is considered difficult by pathologists, as they often have overlapping histological characteristics. Chromosomal translocations have been identified in ~20% of mesenchymal tumors and are considered the drivers of tumor formation. Many translocations have been discovered over the past decade through next-generation sequencing. This technological advancement has also revealed several recurrent gene fusions in vascular tumors.

AREAS COVERED

This review will discuss the various vascular tumors for which recurrent gene fusions have been identified. The gene fusions and the presumed molecular mechanisms underlying tumorigenesis are shown, and potential implications for targeted therapies discussed. The identification of these gene fusions in vascular tumors has improved diagnostic accuracy, especially since several of these fusions can be easily detected using surrogate immunohistochemical markers.

EXPERT OPINION

The identification of gene fusions in a subset of vascular tumors over the past decade has improved diagnostic accuracy, and has provided the pathologists with novel diagnostic tools to accurately diagnose these often difficult tumors. Moreover, the increased understanding of the underlying molecular mechanisms can guide the development of targeted therapeutic strategies.

A unique epithelioid vascular neoplasm of bone characterized by EWSR1/FUS-NFATC1/2 fusions

An increasing number of epithelioid vascular lesions, in particular tumors from the benign and low-grade end of the spectrum, have been characterized by recurrent gene fusions. As a result, the detection of these molecular markers have improved the classification of diagnostically challenging cases. However, despite the significant progress, there are occasional lesions that do not fit in known histologic or molecular groups. Herein, we present five such unclassified epithelioid vascular lesions, which occurred in the bone and showed a distinct morphology composed of alternating vasoformative and solid growth and mild to moderate nuclear pleomorphism. The variegated morphologic appearance resembled that of composite hemangioendothelioma, being distinct from both epithelioid hemangioma and epithelioid hemangioendothelioma, and consistently showed cytologic atypia. Due to their unusual morphologic appearance and negative molecular work-up, targeted transcriptome sequencing was performed in two cases showing the presence of NFATC2 fusions with either EWSR1 or FUS genes. Three additional bone tumors with EWSR1 gene rearrangements were identified by FISH screening of a large cohort of 45 fusion-negative epithelioid vascular neoplasms, one fused to NFATC2 while two others to NFATC1. There were three females and two males, with a wide age range at presentation, mean of 44 years. The lesions occurred in the pelvis, maxillary sinus, and humerus. Two patients presented with polyostotic disease, both located in the pelvic bones. Two patients had available follow-up, one developed two local recurrences in the humerus over a 15-year period, while the other showed no recurrence 4 years subsequent to an en-bloc resection. Tumors were positive for CD31 and ERG, while negative for EMA, CK, synaptophysin, and chromogranin. FISH confirmed this abnormality in all cases, none of them being associated with gene amplifications. Further studies are needed to establish the pathogenetic relationship of this rare molecular subset with other epithelioid vascular tumors and to determine its clinical behavior.

Transarticular epithelioid hemangioma of the ankle-a case of a rare vascular neoplasm

Epithelioid hemangioma of the bone is a rare kind of vascular neoplasm posing a diagnostic challenge because of its ability to mimic malignant tumors. We report a case of a fast-growing, talofibular joint-involving epithelioid hemangioma, which was suspectedly initiated by vascular damage due to trauma and arthroscopy. The ankle mass appeared as a lytic lesion on the CT images and as a T1 hypo-, T2 mildly hyperintense, lobulated structure on the MRI scans. The contrast enhancement pattern was typical to vascular neoplasms. Histologically the lesion consisted of well-formed vessels lined with epithelioid cells with a slightly atypical nuclear morphology, inflammation with a significant number of eosinophils, and low mitotic rate. Immunohistochemistry analysis showed the presence of vascular markers but no rearrangements characteristic of soft tissue sarcomas were registered by the next-generation sequencing. The surgical treatment was curative. The report presents current imaging methods and summarizes the imaging findings of transarticular spreading tumors. The paper also highlights that for the differential diagnosis of vascular tumors showing signs of aggressivity, the pathological analysis is inevitable. Correct diagnosis of the epithelioid hemangioma is essential, as the treatment of more malignant entities is substantially different. An added value of the report is that to the best of our knowledge, a transarticular spreading epithelioid hemangioma of the ankle has never been described before.

Epithelioid Haemangioma of Bone: A Case Series and Comprehensive Literature Review Reappraising the Diagnostic Classification of All Epithelioid Vascular Neoplasms of Bone

Epithelioid vascular neoplasms of the bone are classified by the World Health Organization (WHO) into only two tiers: low-grade epithelioid hemangioma (EH) and a more malignant category including both epithelioid hemangioendothelioma and epithelioid angiosarcoma. The World Health Organization defines bone EH as a locally aggressive neoplasm with no connotation of benign or intermediate malignancy. We reviewed three cases of EH in our lab archives with the perspective of appraising their histomorphological approach toward diagnosis. Patients were in the age range of 15-25 years. The site of the neoplasms ranged from the carpal bones to the metatarsal bones. Histomorphological examination of the lesions showed a nodular growth pattern of a vascular neoplasm without demonstrable vessel origin. The vasoformative area increased from the center to the periphery, with prominent epithelioid morphology of the endothelial cells at the periphery and an associated inflammatory infiltrate comprising eosinophils, lymphocytes, and plasma cells. The growth pattern was diffuse, with extension into the deeper dermis of overlying skin.

Primary Angiosarcoma of Humerus - A Case Report and Literature Review

INTRODUCTION

Osseous angiosarcoma is a very rare tumor of bone with aggressive behavior, propensity for recurrences, and distant metastasis. The etiology of osseous angiosarcoma is uncertain; however, specific risk factors have been recognized. The diagnosis of angiosarcoma of bone demands multimodality imaging in conjunction with histopathological and vascular marker evaluation to aptly differentiate them from other vascular tumors. Treatment of osseous angiosarcoma remains controversial.

CASE REPORT

A 53-year-old male presented with pain and swelling of the right upper 1/3rd of the arm following heaviness while lifting weight for 3 months. He had a history of significant weight loss and appetite with no history of inciting trauma or irradiation in the past. On examination, a diffuse swelling was noted in the right shoulder and right scapular aspect with varied consistency and ill-defined borders and margins. The skin over the swelling was stretched and shiny with dilated engorged veins over it. The plain radiograph of the right shoulder with humerus revealed a large expansile lytic soft-tissue mass in the right proximal humerus with a wide zone of transition without sclerotic margins. Magnetic resonance imaging showed T1 hypointense, T2/PDFS hyperintense large well-defined expansile lytic lesion with multi-loculated cysts, and multiple blood-fluid levels involving right proximal humerus. The patient underwent an incisional biopsy which exhibited angiosarcoma of the humerus. The patient was treated with six cycles of chemotherapy with a mesna, doxorubicin, ifosfamide, and dacarbazine regimen. The patient was still under follow-up.

CONCLUSION

Being a rare clinical entity, controversy exists in angiosarcoma of humerus regarding its etiology and recommended management protocols. Histopathology and immunohistochemistry remain the gold standard in differentiating osseous angiosarcoma from other osseous vascular tumors. The treatment protocol has to be standardized to decrease morbidity and to improve the functional quality of life of the patient.

Novel GATA6-FOXO1 fusions in a subset of epithelioid hemangioma

The genetic hallmark of epithelioid hemangioma (EH) is the presence of recurrent gene fusions involving FOS and FOSB transcription factors, which occur in one-third of the cases. Certain clinical, pathologic, and genotypic correlations have been described, with FOS-related fusions being more often detected in skeletal and cellular variants of EH, while FOSB gene rearrangements are more commonly associated with atypical histologic features and penile location. These fusions are infrequently detected in the cutaneous or head and neck EH. Overall, two-thirds of EH lack these canonical fusions and remain difficult to classify, especially when associated with atypical features and/or clinical presentations. Triggered by an index case of an intravascular soft tissue EH with a novel GATA6-FOXO1 gene fusion by targeted RNA sequencing (Archer® FusionPlex® Sarcoma Panel), we have investigated 27 additional EH cases negative for FOS and FOSB gene rearrangements for this novel abnormality to determine its recurrent potential, and its association with clinical and pathologic features. Four additional EH cases were found to display GATA6-FOXO1 fusions (18%). There were three females and two males, with a mean age of 32 years old. Three lesions occurred in the head and neck (dura, nasopharyngeal, and cheek), one in the back and one in the leg. Two of these lesions were cutaneous and one was intravascular in the subcutis of the leg. Microscopically, the tumors showed a variegated morphology, with alternating vasoformative and solid components, extravasated red blood cells and mild to moderate cytologic atypia. None showed brisk mitotic activity or necrosis. Tumors were negative for FOS and FOSB by immunohistochemistry. In conclusion, we report a new GATA6-FOXO1 fusion in a subset of EH, with a predilection for skin, and head and neck location. The relationship of this novel molecular subset with the more common FOS/FOSB fusion-positive EH remains to be determined.

Epithelioid hemangioendothelioma of bone: A survival analysis of 50 cases from the SEER database (1992-2016)

Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor that may arise in bone. The purpose of this investigation was to determine the clinicopathological features and outcomes of osseous EHE in a large patient series, and to assess whether survival is impacted by demographics, tumor characteristics, or treatment factors. This was a retrospective review of the Surveillance, Epidemiology and End Results (SEER) database from 1992 to 2016. Kaplan-Meier was used to estimate overall survival (OS) and disease-specific survival (DSS). A Cox regression model was used to identify prognostic factors. Fifty patients from 1992 to 2016 with a median age of 54.5 years (IQR, 37–67) were reviewed. For location, 46% (n = 23) of tumors arose from the appendicular skeleton while 38% (n = 19) occurred within the axial skeleton (overlapping EHE: 16%, n = 8). Of the cases with recorded treatment factors, 54.8% (n = 23) had surgery, 26% (n = 13) received radiation, 22% (n = 11) were treated with chemotherapy, and 26% (n = 13) had surgery plus radiation. The 5-year OS probability was 49.2% (95% CI, 23.6–70.6), and the 5-year DSS probability was 63.9% (95% CI, 33.0–83.5). No surgery (surgery: HR, 0.262; 95% CI, 0.07–0.9); p = 0.041) and age older than 50 years (HR, 4.117; 95% CI, 1.1–15.4; p = 0.035) were negative prognostic factors of disease-specific mortality after controlling for confounding variables. There was no association between disease-specific mortality and adjuvant or multimodal therapy. The prognosis of EHE of bone is less than favorable, and the 5-year DSS probability of 64% emphasizes the intermediate grade nature of this tumor subtype. Surgical treatment, when feasible, is associated with a better prognosis.

Concurrent epithelioid hemangioma and diffuse cavernous hemangioma in the rectum clinically mimicking a malignant tumor: a case report

Epithelioid hemangioma is a rare benign vascular tumor that consists of capillary-sized vessels lined by epithelioid endothelial cells. Diffuse cavernous hemangioma is a congenital benign vascular neoplasm consisting of increased dilated vessels. We report a case of epithelioid hemangioma and diffuse cavernous hemangioma that co-occurred in the rectum. To our knowledge, this is the first report in which two rare vascular lesions coexisted. Because both epithelioid hemangioma and diffuse cavernous hemangioma are often clinically confounded by malignant tumors, differentiating these benign lesions from other possible malignant tumors is significant.

Atypical presentation and management of an epithelioid hemangioma: a case report and review of the literature

Background

Epithelioid hemangioma is a rare, benign vascular lesion classically presenting with painless nodules in the head and neck region. Hemangioma lesions are typically small, located within the dermis and subcutaneous tissue, and rarely exceed 10 cm in size. Complete surgical excision, with negative margins, is the recommended treatment as local recurrence is common. We describe an unusual presentation of epithelioid hemangioma that, to our knowledge, has not been previously described in the literature, epithelioid.

Case presentation

We report an atypical case of a large epithelioid hemangioma lesion with deep intramuscular involvement in a 16-year-old male. Ultrasound and MRI showed a hypervascular mass on the patient’s left upper back, and biopsy confirmed the diagnosis. Treatment consisted of preoperative embolization followed by excision and local tissue rearrangement.

Conclusions

Epithelioid hemangiomas are considered uncommon in the pediatric population. Moreover, it is challenging to diagnose these lesions due to their similarities to other vascular anomalies. We aim to increase awareness of this condition and obtain more precision in diagnosis, thus standardizing the approach for those treating individuals with vascular anomalies.

Primary Vascular Tumors of Bone: A Monoinstitutional Morphologic and Molecular Analysis of 427 Cases With Emphasis on Epithelioid Variants

Recent molecular discoveries have refined vascular bone tumor classification. To investigate the clinical relevance of these refinements, we reviewed all cases of primary vascular bone tumors treated at our Institute. On the basis of morphology, cases were assessed immunohistochemically and molecularly. A total of 427 cases of primary vascular tumor of bone with available follow-up and histologic material were retrieved and reclassified according to the most recent diagnostic criteria as follows: 289 hemangiomas, 38 epithelioid hemangiomas, 21 epithelioid hemangioendotheliomas, 2 retiform hemangioendotheliomas, 1 intraosseous papillary intralymphatic angioendothelioma, 24 pseudomyogenic hemangioendotheliomas, and 52 angiosarcomas (of these, 45 were epithelioid angiosarcomas and 7 spindle cell secondary angiosarcoma). Both epithelioid and classic hemangiomas behave as benign tumors with excellent prognosis. The distinction between cellular and conventional type of epithelioid hemangioma was not associated with a different clinical course. Conversely, epithelioid hemangioendothelioma exhibited a more aggressive clinical behavior than hemangioma, with higher rates of multifocality and distant spread. Immunohistochemical positivity for CAMTA1 or TFE3 did not have a prognostic implication. In epithelioid hemangioendothelioma, the presence of morphologic malignant features was associated with reduced disease-free (P=0.064) and overall survival (P=0.055). Pseudomyogenic hemangioendothelioma featured local aggressiveness in 5/24 patients exhibiting a clinical behavior closer to epithelioid hemangioma than epithelioid hemangioendothelioma. Last, 32/45 patients with epithelioid angiosarcoma died of disease with a median survival time of 10 months from diagnosis. In conclusion, the integration of morphologic, immunohistochemical, and molecular features allows a better stratification of primary vascular tumors of bone with significant prognostic and therapeutic implications.

Epithelioid hemangioma of bone harboring FOS and FOSB gene rearrangements: A clinicopathologic and molecular study

The diagnosis of epithelioid hemangioma (EH) remains challenging due to its rarity, worrisome histologic features, and locally aggressive clinical and radiographic presentation. Especially in the bone, EH can be misdiagnosed as a malignant vascular neoplasm due its lytic, often destructive or multifocal growth, as well as atypical morphology. The discovery of recurrent FOS and FOSB gene fusions in the pathogenesis of most EH has strengthened its stand-alone classification, distinct from other malignant epithelioid vascular lesions, such as epithelioid hemangioendothelioma or angiosarcoma. In this study we investigate a group of molecularly confirmed skeletal EH by the presence of FOS or FOSB gene rearrangements to better define its clinical and pathologic characteristics within a homogenous molecular subset. The cohort included 38 patients (25 males, 13 females), with a mean age at diagnosis of 38 years (range, 4-75). Regional, multifocal presentation was noted in 10 cases. Only six cases were correctly recognized as EH by the referring institutions, while most were misdiagnosed as other vascular tumors. Of the 17 patients with follow-up data available, five patients (29%) developed local recurrence after marginal en bloc excision (n = 3) or curettage (n = 2). Local recurrence-free survival rates were 84% at 3 years and 38% at 5 years. No metastasis or disease-related death was identified. Imaging studies exhibited no specific features, showing cortical bone destruction and soft-tissue extension in 14 (38%) cases. FOS gene rearrangements were detected in 28 (74%) of cases, while FOSB rearrangements in 10 (26%) cases. Our results highlight the significant challenges encountered in establishing a correct diagnosis exclusive of the molecular testing, mainly due to its overlap to other malignant epithelioid vascular tumors. Skeletal EH emerges as a genetically defined locally aggressive vascular neoplasm, with a high rate of local recurrence, but lacking the propensity for distant spread.

Angiosarcoma of bone: a retrospective study of the European Musculoskeletal Oncology Society (EMSOS)

Angiosarcoma of bone (B-AS) is a rare malignant tumor of vascular origin. The aim of this retrospective study is to report on treatments and prognosis. Data were collected from the EMSOS website. 80 patients in 9 centers included: 51 male/29 female; median age 54 years (range 17 to 92); 56% with localized disease, 44% metastatic. Primary tumor surgery: 76% (30% amputation, 26% intralesional margins); radiotherapy (RT): 41%; chemotherapy (CT): 47% (56% in metastatic, 41% in localized cases). With a median follow-up of 31 months (range 40 to 309), 5-year overall survival (OS) was 27% (95%CI 16–30): 41% (95%CI 25–56) for localized patients, and 8% (95%CI 0–20) for metastatic (p = 0.002). In metastatic patients, 1 year OS was significantly influenced by chemotherapy response: 67% (95CI% 29–100) for those who responded or had stable disease (n = 7), and 18% (95CI% 0–41) for patients with progressive disease (n = 11), p 0.002. The surgical complete remission (SCR) status was pivotal in localized patients (5-year OS 45% for SCR, 17% no SCR, p = 0.03); also 5-year OS was significantly influenced by age and site of the tumor. After multivariate analysis, the addition of radiotherapy to surgery significantly influenced the disease-free survival (DFS) rate, whereas the use of chemotherapy lost the significance showed at the univariate analysis. Overall, patients with metastatic B-AS have a dismal prognosis, with a prolonged survival in case with a response to chemotherapy. Experimental trials with more active systemic treatment regimens are needed. In patients with localized disease, the patient’s age and site of the tumor are prognostic factors and any effort must be made to achieve an SCR status. No definitive conclusions can be drawn from our data on the use of adjuvant chemotherapy, while the use of adjuvant radiotherapy might improve DSF in patients surgically free of disease.

Treatment of lumbar vertebra epithelioid hemangioma with radiation therapy: a case report

Background

Although epithelioid hemangiomas involving bone have been described in previous case reports and case series, the effects of radiation therapy on vertebral epithelioid hemangioma has not been fully reported. Here we provide a case report of tumor response to radiation therapy in a young adult with a large epithelioid hemangioma involving the fourth lumbar vertebrae.

Case presentation

A 27-year-old Latino man with a past medical history of type 1 diabetes and a 3-year history of low back pain presented to a hospital emergency department following acute worsening of back pain. On transfer to our tertiary medical center, he described the pain as “shock-like” which originated at the lateral aspect of his right hip and radiated down to his right knee. Paresthesia was also reported along the medial aspect of his lower right leg. Imaging included a computed tomography scan and magnetic resonance imaging which revealed fourth lumbar and right iliac lytic bone lesions. Image-guided biopsies of the lytic lesions were consistent with a diagnosis of epithelioid hemangioma and radiation therapy was recommended as the primary treatment. Our patient’s low back and leg pain were initially managed with acetaminophen, oxycodone, pregabalin, and lidocaine patch 5%. He noted improvement in pain after his third fraction of radiation. Pain intensity continued to decline and oxycodone was discontinued.

Conclusions

This case report demonstrates an unusual etiology of back and leg pain in a young man and elucidates the palliative effects of radiation therapy for epithelioid hemangioma involving the lumbar spine.

Multifocal and hormone-dependent epithelioid hemangioendothelioma with osteolysis of the second cervical vertebral body: report of an unprecedented surgical approach by using autologous bone graft

We report the case of a 28-year-old female patient who complained of extreme neck pain when giving birth to a child. Magnetic resonance imaging (MRI) of the cervical spine demonstrated an osteolytic lesion at the second cervical vertebral body (C2). In this presentation, we highlight a transoral surgical approach in order to prevent instability of this osteolytic lesion. To the best of our knowledge, this is the first time that such a route of access has been described for this tumor entity. A histopathologic examination led to the diagnosis of epithelioid hemangioendothelioma. During a follow-up period of 33 months, the patient had no complaints.

Epithelioid hemangioma of bone: A unique case with multifocal metachronous bone lesions

Epithelioid hemangioma of bone is a rare vascular neoplasm with a ubiquitous distribution. To date, up to 25% epithelioid hemangioma of bone presents synchronous bone lesions. We report a unique case of epithelioid hemangioma with multifocal metachronous bone lesions without any fatal outcome observed after a long period. Importantly, a strong nuclear expression of FOSB antibody was detected by immunohistochemical analysis. In this case, the pathologic and radiologic findings are also described. We suggest that epithelioid hemangioma can present multifocal metachronous bone lesions without producing a fatal outcome.

Vascular Tumors of Bone: The Evolvement of a Classification Based on Molecular Developments

The classification of vascular tumors of bone has been under debate over time. Vascular tumors in bone are rare, display highly overlapping morphology, and, therefore, are considered difficult by pathologists. Compared with their soft tissue counterparts, they are more often multifocal and sometimes behave more aggressively. Over the past decade, with the advent of next-generation sequencing, recurrent molecular alterations have been found in some of the entities. The integration of morphology and molecular changes has led to a better characterization of these separate entities.

Unicentric epithelioid hemangioendothelioma of the calcaneus: a case report and review of literature

Background

This review of the literature combined with a clinical case will allow the illustration of a favorable outcome of this variable low grade malignancy, display a role for limb salvage surgery with intralesional treatment, and offer a clinical example of epithelioid hemangioendothelioma, a rare malignancy.

Case presentation

The case report presents a case of solitary epithelioid hemangioendothelioma (EHE) of the calcaneus in a 60-year-old male. Primary vascular tumors of the bone are rare; however, EHE is one of the most common primary malignant vascular tumors to occur in bone. A review of the literature found few cases that involved the calcaneus; those cases found that involved the calcaneus were either part of a multifocal or metastatic disease process. Our case presents a 45-month clinical follow-up of solitary EHE in the calcaneus treated with surgical excision by curettage and cementing.

Conclusion

This case has clinical follow-up greater than 2 years post-operatively and could be a guide for treatment of a rare disorder with a substantial paucity of literature.

Epithelioid hemangioendothelioma of the craniocervical junction; case report and review

Epithelioid hemangioendotheliomas are uncommon vascular neoplasms and their spinal location is even rarer. We report clinical course of a 31-year-old man with an epithelioid hemangioendothelioma at the cranio-cervical junction. A cervical magnetic resonance imaging revealed tumor that caused posterior cervical cord compression. C1,2,3 total laminectomy and surgical excision of the tumor was performed. Postoperative external beam radiation was performed on the surgical field especially around the right vertebral artery. At 2-year follow-up there was no neurological deficit and no tumor recurrence.

Epithelioid hemangioendothelioma of the spine: case report and review of the literature

Epithelioid hemangioendothelioma (EHE) has been described as a rare vascular bone lesion with histological features between hemangioma and high-grade angiosarcoma. Spinal EHE is a quite rare disease with few case reports and series reported in the literature. The tumor cells are positive for vimentin, CD31and CD34, factor VIII related antigen, ERG, and FLI1. Radiological features are not specific; it may appear as an osteolytic lesion. It can present as a multifocal disease in 40% of cases. No clear correlation with age and sex; however, it is slightly more common in males. Focal neck or back pain is the most common presenting symptom. The natural history of spinal EHE is unpredictable, and currently, there is no standard of care for treatment. Treatment options include preoperative embolization, and surgical resection followed by radiotherapy and/or chemotherapy. A 34-year-old previously healthy male presented with mid-thoracic back pain. Magnetic resonance imaging (MRI) of the spine revealed a decrease in vertebral body height at T5 with an enhancing mass. He underwent T5 balloon kyphoplasty and needle vertebral body biopsy. Results of the biopsy samples were non-diagnostic. Approximately 3 months after surgery, the patient presented with unsteady gait. A subsequent MRI revealed progression of the T5 compression fracture with cord compression. The patient subsequently underwent T4-T6 bilateral posterior decompression for epidural tumor and T3-T7 posterior instrumentation with pedicle screws. Pathology of the lesion revealed EHE. The patient was started on local radiation therapy (RT). On follow-up, 3 months after the second surgery, the thoracic spinal pain had improved dramatically. Our review highlights the diagnosis, clinical presentation, and treatment of spinal EHE. Complete resection is associated with good outcome. Radiotherapy has been used in partially resected lesions. However, the role of radiotherapy as primary treatment is not yet defined. Further studies should develop a treatment algorithm for this rare tumour.

Angiosarcoma: clinical and imaging features from head to toe

Angiosarcoma is a rare, aggressive subtype of soft-tissue sarcoma with a propensity for local recurrence and metastasis associated with a generally poor prognosis, unless diagnosed early. Given the vascular endothelial cell origin of angiosarcoma, tumours may develop in essentially any organ; however, there is a predilection for the skin where half of all tumours arise, increasing in prevalence with age. The most common risk factors are chronic lymphoedema and history of radiation. We review the most important radiological findings along the spectrum of angiosarcoma from head to toe throughout the body, including uncommon and rare locations. Key imaging features of angiosarcoma across multiple organ systems will be described, as well as the impact on management and prognosis.

[Protocol for the study of bone tumours and standardization of pathology reports]

Primary bone neoplasms represent a rare and heterogeneous group of mesenchymal tumours. The prevalence of benign and malignant tumours varies; the latter (sarcomas) account for less than 0.2% of all malignant tumours. Primary bone neoplasms are usually diagnosed and classified according to the criteria established and published by the World Health Organization (WHO 2013). These criteria are a result of advances in molecular pathology, which complements the histopathological diagnosis. Bone tumours should be diagnosed and treated in referral centers by a multidisciplinary team including pathologists, radiologists, orthopedic surgeons and oncologists. We analyzed different national and international protocols in order to provide a guide of recommendations for the improvement of pathological evaluation and management of bone tumours. We include specific recommendations for the pre-analytical, analytical, and post-analytical phases, as well as protocols for gross and microscopic pathology.

The debate is still open; benign or malignant: a case report of a multifocal epithelioid haemangioma of fibula

In this case, we report an epithelioid haemangioma (EH) of the fibula with ill-defined multifocal lesions and a resultant pathologic fracture. Based on radiographic appearance, these lesions were initially thought to represent a malignant process, such as primary malignant bone tumour, metastases or multiple myeloma. Osseous EHs are rare. Although they can present as multifocal lesions, the majority of bony EHs are solitary and arise in the diaphysis or metaphysis of long tubular bones, with a predilection for the lower extremity. Non-specific radiological findings, debatable cytological appearance and unpredictable clinical growth patterns commonly cause misdiagnosis of malignancy. To the best of our knowledge, a case of EH with multiple growing lesions of the fibula has not yet been reported in the literature.

Advances in the clinicopathological and molecular classification of cutaneous mesenchymal neoplasms

In recent years, there have been several important refinements in the classification of cutaneous mesenchymal neoplasms, including the description of new tumour types, along with the identification of novel and recurrent molecular genetic findings. In addition to providing new insights into tumour biology, many of these advances have had significant clinical consequences with regard to diagnostics, management, and prognostication. Newly described entities include pseudomyogenic haemangioendothelioma, haemosiderotic fibrolipomatous tumour, and fibroblastic connective tissue naevus, which are reviewed in the context of the principal differential diagnoses and significant clinical implications. Genetic characterization of several soft tissue tumour types that occur in the skin has resulted in the identification of diagnostically useful markers: ALK gene rearrangement with corresponding ALK protein expression by immunohistochemistry in epithelioid fibrous histiocytoma; the WWTR1-CAMTA1 fusion gene with CAMTA1 protein expression in epithelioid haemangioendothelioma; MYC amplification and overexpression in radiation-associated angiosarcoma; and EWSR1 gene rearrangement in cutaneous myoepithelial tumours. Finally, the classification of intradermal smooth muscle tumours and unclassified/pleomorphic dermal sarcoma has been refined, resulting in both improved classification and improved prognostication. Many of the tumour types listed above are encountered not only by specialist dermatopathologists, but also by practising general surgical pathologists, and this review should therefore provide a widely applicable update on the histological and molecular classification of cutaneous mesenchymal neoplasms, along with the appropriate use of ancillary diagnostic tests, in particular immunohistochemistry, in the evaluation of such lesions and their histological mimics.

Epithelioid hemangioma of brachial artery: report of a case and review of the literature

Epithelioid hemangioma (EH) is an uncommon benign vascular lesion, also known as angioblastic lymphoid (or angiolymphoid) hyperplasia with eosinophilia, characterized by an unclear etiopathogenesis.

It usually affects young to middle-aged adults and develops in the head and neck region, as painless cutaneous or subcutaneous reddish papules or nodules.

Large vessels involvement is extremely rare, and to date only two cases affecting the brachial artery have been cited in literature.

In this report we present a further case of EH of the brachial artery and review the pertinent literature.

Frequent FOS Gene Rearrangements in Epithelioid Hemangioma: A Molecular Study of 58 Cases With Morphologic Reappraisal

Epithelioid hemangioma (EH) is a unique benign vasoformative tumor composed of epithelioid endothelial cells. Although a small subset of EHs with atypical features harbor ZFP36-FOSB fusions, no additional genetic abnormalities have been found to date in the remaining cases. On the basis of a novel FOS-LMNA gene fusion identified by RNA sequencing in an index case of a skeletal EH with typical morphology, we sought to investigate the prevalence of FOS rearrangement in a large cohort of EHs. Thus 57 additional EH cases lacking FOSB rearrangements were studied for FOS gene abnormalities by fluorescence in situ hybridization, and results were correlated with morphologic appearance and clinical presentation. The EHs were subclassified as typical (n=25), cellular (n=21), and angiolymphoid hyperplasia with eosinophilia (ALHE) (n=12) variants. The ALHE was defined as an EH with a vascular "blow-out" pattern associated with a variable degree of inflammation. There were 17 (29%) cases bearing FOS gene rearrangements among 58 cases tested, including 12 male and 5 female patients, with a mean age of 42 years. Most FOS-rearranged EHs occurred in the bone (10) and soft tissue (6), whereas only 1 case was cutaneous. The predominant anatomic site was the extremity (12), followed by trunk (3), head and neck (1), and penis (1). The incidence of FOS rearrangement was significantly higher in bone (59%, P=0.006) and lower in head and neck (5%, P=0.009). Twelve of the FOS-rearranged cases were cellular EH (P=0.001) associated with moderate mitotic activity (2 to 5/10 HPF) and milder inflammatory background. All 12 ALHE cases lacked FOS gene abnormalities, suggesting different pathogenesis. In conclusion, FOS rearrangement was present in a third of EHs across different locations and histologic variants; however, it was more prevalent in cellular EH and intraosseous lesions, compared with those in skin, soft tissue, and head and neck. This genetic abnormality can be useful in challenging cases, to distinguish cellular EHs from malignant epithelioid vascular tumors. These results also suggest that dysregulation of the FOS family of transcription factors through chromosomal translocation is as a key event in the tumorigenesis of EH except for the ALHE variant.

Epithelioid Hemangioendothelioma of the Distal Radius: A Case Report

Epithelioid hemangioendothelioma is a rare vascular tumor with cytologic behavior between angiosarcoma and hemangioma. We present the case of a 58-year-old male with primary epithelioid hemangioendothelioma of the distal radius measuring 6.2 × 5 cm with extension into the pronator quadratus and brachioradialis muscles. We discuss our approach to performing a limb-sparing resection combined with reconstruction to preserve upper extremity function. A review of the clinical, radiographic, and pathologic features of epithelioid hemangioendothelioma is also presented.

Combined or Serial Liver and Lung Transplantation for Epithelioid Hemangioendothelioma: A Case Series

Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor with variable biological and clinical behavior. There is increasing experience with liver transplantation (LiTx) for hepatic EHE, even in cases of extrahepatic disease localization. Until now, no cases of lung transplantation (LuTx) had been reported for pulmonary EHE. This report describes three cases of EHE with multifocal disease in patients who underwent either serial or combined LiTx and LuTx.

Clinical Applications of Molecular Markers in Bone Tumors

Pathologic diagnosis of primary bone neoplasms can be challenging primarily due to rarity of the disease entities, overlapping imaging and histologic findings, and lack of tumor-specific immunohistochemical stains. Although slow to evolve, in recent years there has been a rapid advance in the discovery of new and novel molecular markers in primary bone neoplasms, which has enhanced diagnostic accuracy and has shed light into their pathogenesis. Modern technological approaches such as next-generation sequencing including RNA sequencing are serving as "rapid discovery platforms" for new and novel mutations and translocations with diagnostic, prognostic, and possible therapeutic applicability. As next-generation sequencing technologies are finding their place in clinical laboratories, one could envision routine testing for mutations spanning across a gene or translocations with multiple breakpoints and partner genes. This review will focus on the clinical relevance and applicability of molecular markers in primary bone neoplasms with examples.

Epithelioid Hemangioendothelioma of Tibia and Talus: A Case Report

Epithelioid hemangioendothelioma (EHE) of the bone is extremely uncommon and consists of less than 1% of primary bone tumors. It is characterized by epithelioid endothelial cells and has variable biological behavior. EHE is more likely to occur between 20 and 30 years of age. Approximately half of EHE present with multifocal disease. Since the behavior of these tumors is intermediate, it is important to not misdiagnose EHE as an angiosarcoma. Here we describe the case of a 43-year-old male who presented with pain and swelling of the leg and ankle to Dr. Ram Manohar Lohia Hospital, India. Radiography and computed tomography of the ankle and leg were performed and suggested an expansile lytic lesion involving the distal tibia and talus bone. The lesion was excised and ankle arthrodesis performed. Histological evaluation of the lesion demonstrated the presence of EHE of the tibia and talus.

Fusion events lead to truncation of FOS in epithelioid hemangioma of bone

Epithelioid hemangioma of bone is a locally aggressive vascular neoplasm. It can be challenging to diagnose because of the wide histological spectrum, which can make it difficult to differentiate from other vascular neoplasms such as epithelioid hemangioendothelioma or epithelioid angiosarcoma. COBRA-FISH karyotyping identified a balanced t(3;14) translocation. Transcriptome sequencing of the index case and two other epithelioid hemangiomas revealed a recurrent translocation breakpoint involving the FOS gene, which was fused to different partners in all three cases. The break was observed in exon 4 of the FOS gene and the fusion event led to the introduction of a stop codon. In all instances, the truncation of the FOS gene would result in the loss of the transactivation domain (TAD). Using FISH probes we found a break in the FOS gene in two additional cases, in none of these cases a recurrent fusion partner could be identified. In total, FOS was split in 5/7 evaluable samples. We did not observe point mutations leading to early stop codons in any of the 10 cases where RNA was available. Detection of FOS rearrangement may be a useful diagnostic tool to assist in the often difficult differential diagnosis of vascular tumors of bone. Our data suggest that the translocation causes truncation of the FOS protein, with loss of the TAD, which is thereby a novel mechanism involved in tumorigenesis.

Primary pseudomyogenic haemangioendothelioma of bone: report of two cases

Pseudomyogenic haemangioendothelioma (epithelioid sarcoma-like haemangioendothelioma) is a recently described, rarely metastasising neoplasm of the soft tissues that often presents as multiple discontinuous nodules in different tissue planes of a limb. This tumour type is extremely difficult to diagnose because no morphological evidence suggestive of endothelial differentiation is present to confirm a radiological suspicion of vascular neoplasm. All but one case published in the literature underline that bone involvement is secondary to deep and superficial soft tissue nodules. Here, we report two cases of primary bone pseudomyogenic haemangioendothelioma occurring in the radius and cuboid bone with a multifocal presentation.

A rare case of intravascular epithelioid hemangioendothelioma of the cephalic vein treated with surgery and postoperative radiation therapy: a case report and review of the literature

INTRODUCTION

Epithelioid hemangioendothelioma (EHE) is a rare endothelial tumor with an intermediate grade of malignancy. Few cases of primary vascular hemangioendothelioma have been described in the literature. Surgery is the treatment of choice, but radiation therapy and chemotherapy should also be considered in particular cases.

CASE PRESENTATION

We present the case of a 44-year-old Caucasian woman affected by EHE of the cephalic vein, treated by complete surgical removal of the mass and postoperative local radiation therapy. At 5-year follow-up, our patient is alive, with no signs of local or distant relapse and with no late radiation-related effects.

CONCLUSIONS

Postoperative radiotherapy may play a role in cases in which tumor margins are close or cannot be assessed or when high-risk features are present.

Bone multicentric epithelioid hemangioendothelioma of the lower and upper extremities with pulmonary metastases: A case report

The present study reports a rare case of bone multicentric epithelioid hemangioendothelioma (EH) involving the upper and lower extremities simultaneously, with visceral involvement of the lung. Osteolytic lesions were first identified in the right distal femur and proximal tibia. Slight increased radionuclide uptake was observed in the right shoulder joint on bone scintigraphy, however, this was ignored, as no clinical symptoms were present. The patient was initially misdiagnosed with multifocal chondroblastoma, and an extra-articular curettage of lesions was performed in the proximal tibia and medial femoral condyle, which was filled with bone cement. The histopathological diagnosis was corrected post-operatively following immunohistochemical analysis, which indicated EH, and subsequently, an amputation of the right leg at thigh level was performed. In addition, multiple lytic lesions in the right shoulder joint and pulmonary metastases were identified on whole-body radiological examination. Radiotherapy was administered to the right shoulder joint, however, the patient refused chemotherapy or further surgery. At 15 months after the initial surgery, the patient currently remains alive. This case indicates that an improved understanding with regard to the clinical features of this disease may prevent misdiagnosis and improve EH treatment.

Primary angiosarcoma of bone: a retrospective analysis of 60 patients from 2 institutions

BACKGROUND

Angiosarcoma of bone is a rare high-grade malignant vascular tumor. The literature regarding treatment and outcome of patients with this tumor is limited.We performed a 2 institutional retrospective study to analyze treatment and survival of patients with angiosarcoma of bone.

PATIENTS AND METHODS

We reviewed patients with the histologic diagnosis of primary angiosarcoma of bone treated from 1980 to 2009. Demographic details, histology, treatment, and survival were reviewed.

RESULTS

A total of 38 men and 22 women (median age, 54 y) were recruited. Most lesions occurred in the femur and the pelvis. Metastatic disease at presentation was diagnosed in 24 patients (40%). Forty-three patients underwent surgery, with 30 of them achieving surgical complete remission (SCR). Radiotherapy was applied to 17 patients, and chemotherapy to 13/35 and 15/22 patients with localized and metastatic disease, respectively.The 5-year overall survival (OS) was 20%: 33% for patients with localized disease and 0% for metastatic patients. Higher 5-year OS was reported for patients who achieved SCR (46%) than for those who did not (0%). In nonmetastatic patients, a trend toward improved survival was observed after SCR and adjuvant chemotherapy based on cisplatin, doxorubicin, and ifosfamide.Fifteen patients received chemotherapy for metastases. Two RECIST partial responses of 13 evaluable patients were documented (paclitaxel [n=1] and doxorubicin [n=1]). Stable disease was observed in 2 patients.

CONCLUSIONS

Complete surgical resection is essential for outcome. Survival of patients with metastatic or unresectable disease is very poor. Activity of taxanes and anthracycline was observed in the metastatic setting and merits further evaluation.

A Rare Cause of Postoperative Bleeding from A Lytic Lesion of Calcaneum

Introduction:

Post-operative excessive bleeding can be due to various causes, which may platelet deficiency, both quantitative and qualitative, vascular disorder, clotting factor defects and excessive fibrinolysis. Rarely can be due to some undiagnosed malignant tumours. Angiosarcoma of bone is an exceedingly rare primary bone malignancy. We report an interesting and rare case of an intraosseous angiosarcoma that presented as an excessive postoperative bleeding with diagnostic dilemma.

Case Report:

A twenty eight year old gentleman admitted to our hospital with history of continuous bleeding from surgical site over left heel since three months. About six months ago he was evaluated elsewhere for a painful progressive lesion in the left calcaneum. Following which he underwent curettage of lesion with bone grafting. One month after this he was re-operated for recurrence with curettage with bone cementing. Curetted material on both occasions was reported as aneurysmal bone cyst. One month following the second surgery, surgical scar over the outer aspect of left heel opened out and started to bleed continuously. X rays and MRI done before surgical treatment were suggestive of aneurysmal bone cyst Investigations for clotting and bleeding disorders were normal. The granulation tissue from the floor of the cavity was curetted and sent for histopathology, which was reported as angiosarcoma.

Conclusion:

Intraosseous angiosarcoma is a rare primary bone tumour. The diagnosis is often delayed because of the non-specific clinical presentation and radiological features. Clinicopathological correlation is very important to differentiate aneurysmal bone cyst from the aggressive type of vascular malignancies. The clinical course of disease is aggressive, as demonstrated by this current case. The initial biopsies done twice at curettage were not diagnostic and suggested the presence of a benign aneurysmal bone cyst. Due to the excessive postoperative bleeding, repeat biopsy performed which diagnosed angiosarcoma.

Epithelioid hemangioendothelioma of the spine: results at seven years of average follow-up in a series of 10 cases surgically treated and a review of literature

PURPOSE

To review a series of ten cases with epithelioid hemangioendothelioma of the spine, that have undergone surgery to describe clinical presentation, results and complications associated with surgical treatment; a review of literature reporting the main characteristics of the cases already published has been reported.

METHODS

A review of patients affected by epithelioid hemangioendothelioma surgically treated by the senior author from 1995 to 2012 was carried out. Ten cases were identified and clinical and radiological characteristics, therapy, complications and survival were valued.

RESULTS

Wide margin was achieved in two out of ten cases, marginal margin in seven and intralesional margin in one case. Average intraoperative blood loss was about 2,800 ml. Reported complications were one case of cord injury, one of dural tear, two cases of massive blood loss, a case of reconstruction failure, a wound dehiscence with deep infection, a pneumonia episode and a deep vein thrombosis with pulmonary embolism. Average follow-up was 84.4 months. Two local recurrences, after 32 and 37 months and two deaths for metastasis, after 14 and 36 months, were reported. Although several chemotherapy protocols are available for the treatment of EH of soft tissue, they are not relevant for the bone.

CONCLUSIONS

Wide surgery is probably associated with a better prognosis. Indeed most deaths and local recurrences reported in literature happened after intralesional surgery or chemotherapy/RT alone. The presenting study suggests that the best approach to achieve long-term local control and a major survival could be wide surgery, nevertheless more cases series are necessary to verify survival rate.

ZFP36-FOSB fusion defines a subset of epithelioid hemangioma with atypical features

Epithelioid hemangioma (EH) is a benign neoplasm with distinctive vasoformative features, which occasionally shows increased cellularity, cytologic atypia, and/or loco-regional aggressive growth, resulting in challenging differential diagnosis from malignant vascular neoplasms. Based on two intraosseous EH index cases with worrisome histologic features, such as the presence of necrosis, RNA sequencing was applied for possible fusion gene discovery and potential subclassification of a novel atypical EH subset. A ZFP36-FOSB fusion was detected in one case, while a WWTR1-FOSB chimeric transcript in the other, both were further validated by fluorescence in situ hybridization (FISH) and reverse transcription polymerase chain reaction (RT-PCR). These abnormalities were then screened by FISH in 44 EH from different locations with seven additional EH revealing FOSB gene rearrangements, all except one being fused to ZFP36. Interestingly, 4/6 penile EH studied showed FOSB abnormalities. Although certain atypical histologic features were observed in the FOSB-rearranged EH, including solid growth, increased cellularity, mild to moderate nuclear pleomorphism, and necrosis in 3/9 cases, no overt sarcomatous areas were discerned to objectively separate the lesions from the fusion-negative EH. No patient has developed recurrence to date, but the follow-up was relatively limited and short to draw definitive conclusions regarding behavior. Although FOSB-rearranged EH do not show significant morphologic overlap with SERPINE1-FOSB fusion-positive pseudomyogenic hemangioendothelioma, FOSB oncogenic activation is emerging as an important event in these benign and intermediate groups of vascular tumors.