Angiosarcoma: hiding in plain sight.

Angiosarcoma is a rare, aggressive soft-tissue sarcoma of endothelial origin that necessitates early recognition, diagnosis, and treatment. The most commonly reported presentation consists of violaceous patches and plaques on the head and neck of elderly white men, with fewer reports affecting patients with Skin of Color. Most cases of angiosarcoma are idiopathic and tend to recur locally with early metastasis, conferring a poor prognosis. We report a case of an 83-year-old Fitzpatrick skin type IV man who presented with a large violaceous-to-black mamillated plaque on the frontotemporal scalp that was clinically highly suggestive of cutaneous angiosarcoma. However, unrevealing histopathology complicated our diagnostic process and delayed management. Immunohistochemistry was invaluable in determining the diagnosis of angiosarcoma. Our case highlights the aggressive nature of cutaneous angiosarcoma, necessitating close clinicopathologic correlation to confirm the diagnosis and initiate treatment.

Primary Epithelioid Angiosarcoma of the Submandibular Gland-A Case Report with Histology-Cytology Correlation and Comprehensive Molecular Analysis.

BACKGROUND: Angiosarcoma is a sarcoma that occurs in a range of tissue types, and only rarely in the salivary glands, showing a predilection for the parotid glands of older patients. Preoperative diagnosis may be challenging, especially on cytology, with significant morphological overlap with high-grade primary salivary gland carcinomas. The molecular alterations of this rare salivary gland neoplasm are also not well-characterized. METHODS AND RESULTS: We present a case of right submandibular gland swelling in a 73-year-old male. On fine needle aspiration, including immunohistochemical stains on cell block, the tumor was initially diagnosed as poorly differentiated carcinoma. Resection of the submandibular gland revealed epithelioid angiosarcoma. We performed molecular work-up of the tumor, utilizing targeted next-generation sequencing, DNA methylation profiling and fluorescence in-situ hybridization. Histopathologic assessment revealed an infiltrative tumor comprising solid sheets of epithelioid cells. The tumor cells formed haphazardly anastomosing vascular channels with intracytoplasmic lumina containing red blood cells. On immunohistochemistry, the tumor cells were positive for CD31, CD34 and ERG. Approximately 40% of the tumor cells showed nuclear expression of GATA3. A pathogenic TP53 R267W mutation was detected on next-generation sequencing. DNA methylation analysis did not cluster the tumor with any known sarcoma type. Copy number analysis showed possible MYC amplification and CDKN2A losses, although only the latter was confirmed on fluorescence in-situ hybridization. CONCLUSION: Epithelioid angiosarcoma is an important differential diagnosis to high-grade salivary gland carcinoma. In particular, GATA3 expression may be encountered in both angiosarcoma and high-grade salivary gland carcinomas and cause diagnostic confusion. Identification of TP53 mutations and CDKN2A losses suggest shared oncogenic pathways with soft tissue angiosarcomas, and should be further investigated.

Angiosarcoma: clinical outcomes and prognostic factors, a single-center analysis.

PURPOSE: This study sought to investigate oncological outcomes and prognostic factors for patients with angiosarcomas (AS). METHODS: This single-center, retrospective cohort study, analyzed histopathologically confirmed AS cases. Primarily diagnosed, locally recurrent and metastatic AS were included. Overall survival (OS), local control (LC) and local progression-free survival (LPFS) were assessed by Kaplan-Meier estimator. Multivariable Cox regression analysis was performed to detect factors associated with OS and LPFS. RESULTS: In total, 118 patients with a median follow-up of 6.6 months were included. The majority presented with localized disease (62.7%), followed by metastatic (31.4%) and locally recurrent (5.9%) disease. Seventy-four patients (62.7%) received surgery, of which 29 (39.2%) were treated with surgery only, 38 (51.4%) with surgery and perioperative radiotherapy or chemotherapy, and 7 (9.4%) with surgery, perioperative radiotherapy and chemotherapy. Multivariable Cox regression of OS showed a significant association with age per year (hazard ratio (HR): 1.03, p = 0.044) and metastatic disease at presentation (hazard ratio: 3.24, p = 0.015). For LPFS, age per year (HR: 1.04, p = 0.008), locally recurrent disease at presentation (HR: 5.32, p = 0.013), and metastatic disease at presentation (HR: 4.06, p = 0.009) had significant associations. Tumor size, epithelioid components, margin status, and perioperative RT and/or CTX were not significantly associated with OS or LPFS. CONCLUSION: Older age and metastatic disease at initial presentation status were negatively associated with OS and LPFS. Innovative and collaborative effort is warranted to overcome the epidemiologic challenges of AS by collecting multi-institutional datasets, characterizing AS molecularly and identifying new perioperative therapies to improve patient outcomes.

Imaging primary cardiac angiosarcoma: case-based illustrations with multimodality imaging and emphasis on the role of positron emission tomography-CT.

Primary cardiac angiosarcomas are extremely rare, highly aggressive tumours with rapid progression and high metastatic capability. More than 60% of tumours are detected after the onset of a metastatic disease. In the two cases presented, we demonstrate the role of muti-modality imaging in the diagnosis of the lesion and provide valuable input in prognosticating the disease burden. In both cases, the diagnosis was suspected initially by imaging, based on radiological observations, before the final histopathology confirmation was made. Positron emission tomography- (PET-CT) was a critical component of the diagnostic workup for the detection of disease extent and volume of total disease burden. Hence, PET-CT imaging should be performed in all aggressive appearing cardiac tumours. In view of misleading clinical presentation, we suggest that aggressive workup to be performed in suspected patients. Young patients presenting with vague symptoms and those with recurrent, unresolving, unexplained pericardial effusion deserves special consideration.

Porcine-derived Acellular Dermal Matrix for Temporary Soft Tissue Coverage in Locally Advanced Angiosarcoma of the Face - A Soft Tissue Odyssey?

BACKGROUND/AIM: Angiosarcomas of the face are rare but present significant treatment challenges due to their origin in the supportive tissues of blood or lymphatic vessels. Achieving optimal balance between oncological efficacy and aesthetic outcomes requires a multidisciplinary approach, particularly in cases where radical R0 resection is necessary. Delays often occur, especially during histopathological examinations, which can complicate primary plastic reconstruction before definitive pathological findings. CASE REPORT: To address this issue, we present a case with the use of porcine-derived acellular dermal matrix for temporary soft tissue coverage as a viable option in a case of angiosarcoma of the face. This is particularly useful in situations where frozen sections risk the loss of critical anatomical structures and intraoperative diagnosis is not feasible. This approach allowed for satisfactory wound coverage and granulation during diagnostic phases, paving the way for oncologically manageable situations and functional rehabilitation. CONCLUSION: Temporary soft tissue coverage with porcine-derived acellular dermal matrix is a valuable option in tumor surgery of rare and complex situations.

Prognostic value of tumour-related factors associated with canine retroperitoneal hemangiosarcoma in comparison with other anatomic presentations: A retrospective observational study.

BACKGROUND: Dogs with retroperitoneal hemangiosarcoma (HSA) exhibit variable postoperative median survival times (MST). OBJECTIVE: To retrospectively evaluate the prognostic value of selected tumour-related factors, such as tumour size, rupture, invasion into adjacent tissue, involvement of lymph node and distant metastasis, they were analysed in dogs with retroperitoneal HSA. METHODS: Ten dogs with retroperitoneal HSA managed solely with surgical excision were reviewed and compared with spleen (71) and liver (9) HSA. The Kaplan-Meier method and log-rank analysis were used compare MSTs between factors. Multivariable Cox proportional-hazard analysis was used to compare differences between arising sites. RESULTS: Retroperitoneal HSA showed comparatively longer postoperative MST compared with that of spleen and liver HSA and demonstrated significantly longer MST (p = 0.003) for tumours ≥5 cm (195 days) than <5 cm (70 days). Spleen HSA revealed significantly shorter MSTs in involvement of distant lymph nodes (23 days) and distant metastasis (39 days) than those in negative (83 days, p = 0.002 and 110 days, p < 0.001, respectively). Liver HSA also revealed significantly shorter MST (16.5 days compared with 98 days, p = 0.003) for distant metastasis. Additionally, hazard ratios (HRs) and their forest plot for overall HSA revealed as poor prognostic factors, arising sites (spleen; HR 2.78, p = 0.016 and liver; HR 3.62, p = 0.019), involvement of distant lymph nodes (HR 2.43, p = 0.014), and distant metastasis (HR 2.86, p < 0.001), and as better prognostic factor of tumour size ≥5 cm (HR 0.53, p = 0.037). CONCLUSION: In combination with overall HSA, retroperitoneal HSA shows comparatively longer postoperative MST compared to spleen and liver HSA, associated with tumour size ≥5 cm suggesting better prognostic factor.

Hemangiosarcoma Cells Promote Conserved Host-derived Hematopoietic Expansion.

Hemangiosarcoma and angiosarcoma are soft-tissue sarcomas of blood vessel-forming cells in dogs and humans, respectively. These vasoformative sarcomas are aggressive and highly metastatic, with disorganized, irregular blood-filled vascular spaces. Our objective was to define molecular programs which support the niche that enables progression of canine hemangiosarcoma and human angiosarcoma. Dog-in-mouse hemangiosarcoma xenografts recapitulated the vasoformative and highly angiogenic morphology and molecular characteristics of primary tumors. Blood vessels in the tumors were complex and disorganized, and they were lined by both donor and host cells. In a series of xenografts, we observed that the transplanted hemangiosarcoma cells created exuberant myeloid hyperplasia and gave rise to lymphoproliferative tumors of mouse origin. Our functional analyses indicate that hemangiosarcoma cells generate a microenvironment that supports expansion and differentiation of hematopoietic progenitor populations. Furthermore, gene expression profiling data revealed hemangiosarcoma cells expressed a repertoire of hematopoietic cytokines capable of regulating the surrounding stromal cells. We conclude that canine hemangiosarcomas, and possibly human angiosarcomas, maintain molecular properties that provide hematopoietic support and facilitate stromal reactions, suggesting their potential involvement in promoting the growth of hematopoietic tumors. SIGNIFICANCE: We demonstrate that hemangiosarcomas regulate molecular programs supporting hematopoietic expansion and differentiation, providing insights into their potential roles in creating a permissive stromal-immune environment for tumor progression.

Proposed diagnostic and prognostic markers of primary malignant hepatic vascular neoplasms.

INTRODUCTION: Primary malignant hepatic vascular tumors with various malignant potentials include epithelioid hemangioendothelioma (EHE) and angiosarcoma (AS), which may overlap pathologically. This study aimed to compare the pathological findings of hepatic EHE with those of AS, in association with patient outcomes. METHODS: Fifty-nine histologically confirmed patients with 34 EHE and 25 AS were admitted to a tertiary hospital from 2003 to 2020. Their EHE and AS pathological features were compared. Immunohistochemistry for CD31, ERG, CAMTA-1, TFE3, P53, and Ki-67 labeling was performed on paraffin-embedded blocks. Markers, along with histological findings, were analyzed for the purposes of diagnostic and prognostic significance by multivariate analysis. RESULTS: CAMTA-1 was 91.2% positive in EHE, but negative in AS (p = < 0.001). AS was significantly correlated to an aberrant p53 expression, high Ki-67 labeling, and high mitotic activity, compared to EHE (all, p = < 0.001). EHE can be classified as low grade (LG) and high grade (HG) using the prognostic values of mitotic activity and ki-67 labeling (sensitivity = 1, specificity = 1). Low grade-EHE showed significantly better overall survival than high grade-EHE (p = 0.020). CONCLUSIONS: Immunohistochemistry for CAMTA-1, P53, and Ki-67 labeling may help distinguish EHE and AS in histologically ambiguous cases, especially small biopsied tissue. Moreover, the combination of mitotic activity and Ki-67 labeling can be a prognostic factor for EHE with various clinical features.

Recurrent fever leading to the diagnosis of an angiosarcoma of the adrenal gland: a case report.

BACKGROUND: Angiosarcoma of the adrenal gland is a very rare malignant vascular neoplasm. The clinical symptoms are atypical or completely absent. Angiosarcomas of the adrenal gland are therefore often discovered incidentally, and the diagnosis is made histologically after resection. CASE PRESENTATION: A 46-year-old white Spanish male who was a previous smoker and nondrinker and was slightly overweight (92 kg, 176 cm, body mass index 29.7 kg/m2) with no relevant medical history presented to the internal medicine emergency department of our hospital with an unclear 12 cm tumor of the right adrenal gland. Prior to the computed tomography scan, he had had persistent evening fevers for 4 months and unintentional weight loss of 5 kg. The laboratory results showed anemia and an elevated C-reactive protein, but no hormone production. We performed an open adrenalectomy of the right adrenal gland. Finally, the histologic findings revealed an angiosarcoma of the adrenal gland. CONCLUSION: Even though angiosarcomas of the adrenal gland are rare, the differential diagnosis of an angiosarcoma should be considered if a malignant tumor of the adrenal gland is suspected. Treatment decisions should be made on an interdisciplinary basis and preferably in a specialized center. Owing to the rarity of angiosarcomas of the adrenal gland, it is necessary to continue to share clinical experience to gain a better understanding of this particular tumor entity.

A rare case of epithelioid angiosarcoma.

Epithelioid angiosarcoma is a rare high-grade vascular neoplasm with a poor prognosis. We present an anticoagulated 77-year-old man, with a history of popliteal/soleal vein thrombosis in the previous month, complaining of ipsilateral persistent lower limb pain and claudication. Absent popliteal/distal pulses prompted an arterial doppler ultrasound (DUS), revealing thrombosis of the distal superficial femoral artery and a popliteal mass. As the arterial wall's integrity could not be appropriately evaluated by DUS, adventitial cystic disease of the popliteal artery was suspected. Computed tomography angiography and magnetic resonance imaging findings were also suggestive. Due to refractory pain, he was submitted to a popliteal mass excision along with a femoral-posterior tibial bypass. Pathology revealed an epithelioid angiosarcoma. He was referred to a Sarcoma Center, requiring hospitalization for agitation and fever. A positron emission tomography (PET) scan revealed extensive lower limb disease persistence and distant metastases. He died on the 56th day after surgery. To our knowledge, there are only 15 cases of angiosarcoma of the popliteal artery described in the literature. Ours stands out as the first one unrelated to a popliteal aneurysm. Being a highly-aggressive tumor, an early diagnosis is challenging but essential to a successful treatment, warranting the need for suspicion of this neoplasm. An early core biopsy or surgical sample may expedite the diagnosis.

Etiology, pathogenesis, and management of angiosarcoma associated with implants and foreign body: Clinical cases and research updates.

Angiosarcomas are rare and highly malignant soft tissue sarcomas originating from endothelial cells lining the lymphatic or vascular system. While they predominantly emerge from (sub)cutaneous regions, occurrences have been reported throughout the body. The etiology of angiosarcoma remains elusive in most clinical cases. Nevertheless, several prognosis risk factors play a pivotal role, including chronic lymphedema, therapeutic irradiation, environmental carcinogens, familial syndromes, and the presence of foreign materials like metallic objects and biomedical implants. Despite evidence implicating retained foreign material in angiosarcoma development, understanding its prognosis and pathogenesis remains limited. The pathogenesis of angiosarcoma appears to involve a complex interplay of chronic inflammation, tissue remodeling, and genetic factors that create a conducive microenvironment for malignant transformation. Management of these sarcomas remains challenging due to their infiltrative nature owing to the high chance of metastasis and local recurrence. The primary treatment modalities currently include surgery, radiotherapy, and chemotherapy, but recent advances in targeted immunotherapy and gene therapy hold promise for more effective approaches. This comprehensive review delves into the potential etiological and pathogenic roles of foreign materials, such as metallic objects, biomedical implants, and biomaterials, in the development of angiosarcoma. Further research into the underlying molecular mechanisms could provide valuable insights for tailored management and developing novel targeted therapeutic strategies.

Generation of sarconoids from angiosarcoma patients as a systematic-based rational approach to treatment.

Angiosarcoma is a rare subtype of malignant neoplasm originating from vascular or lymphatic endothelial cells; its low incidence has posed significant challenges for comprehensive investigations into its pathogenic mechanisms and the development of innovative treatment modalities through in vitro and in vivo models. Recent endeavors spearheaded by patient-partnered research initiatives have aimed to elucidate the intricacies of angiosarcomas by leveraging biological omics approaches, with the overarching objective of enhancing prognostic indicators and therapeutic options for this uncommon pathology. To bridge the gap between preclinical research and translational applications, we engineered angiosarcoma-derived organoids from surgically resected primary tumors, hereafter referred to as "sarconoids," as a proof-of-concept model. A novel protocol for the establishment of these sarconoids has been developed and validated. To ensure that the sarconoids faithfully recapitulate the heterogeneity and complexities of the patients' original tumors, including transcriptomic signatures, cell-type specificity, and morphological traits, exhaustive histological and transcriptomic analyses were conducted. Subsequently, we expanded the scope of our study to include an evaluation of a sarconoid-based drug screening platform; for this purpose, a drug library (AOD IX), supplied by the National Cancer Institute's Developmental Therapeutics Program, was screened using 96-well plates. Our findings suggest that sarconoids can be reliably generated from angiosarcoma patient-derived tissues and can serve as accurate models for evaluating therapeutic responses, thereby holding far-reaching implications for translational research and clinical applications aimed at advancing our understanding and treatment of angiosarcoma.

Clinicopathologic and molecular correlates to neoadjuvant chemotherapy-induced pathologic response in breast angiosarcoma.

Both primary and secondary breast angiosarcoma (AS) are characterized by multifocal presentation and aggressive behavior. Despite multimodality therapy, local and distant relapse rates remain high. Therefore, neoadjuvant chemotherapy (NACT) is employed to improve the R0 resection rates and survival, but its benefits remain controversial. Herein, we investigate pathologic and molecular correlates to NACT-induced histologic response in a group of 29 breast AS, 4 primary and 25 radiation-associated (RA). The two NACT regimens applied were anthracycline- and non-anthracycline-based. The pathologic response grade was defined as: I: ≤ 50%, II: 51%-90%, III: 91%-99%, and IV: 100%. An additional 45 primary AS and 102 RA-AS treated by surgery alone were included for survival comparison. The genomic landscape was analyzed in a subset of cases and compared to a cohort of AS without NACT on a paired tumor-normal targeted DNA NGS platform. All patients were females, with a median age of 31 years in primary AS and 68 years in RA-AS. All surgical margins were negative in NACT group. The NACT response was evenly divided between poor (Grades I-II; n = 15) and good responders (Grades III-IV; n = 14). Mitotic count >10/mm2 was the only factor inversely associated with pathologic response. By targeted NGS, all 10 post-NACT RA-AS demonstrated MYC amplification, while both primary AS harbored KDR mutations. TMB or other genomic alterations did not correlate with pathologic response. All four patients with Grade IV response remained free of disease. The good responders had a significantly better disease-specific survival (p = 0.04). There was no survival difference with NACT status or the NACT regimens applied. However, NACT patients with MYC-amplified tumors showed better disease-free survival (p = 0.04) compared to MYC-amplified patients without NACT. The overall survival of NACT group correlated with size >10 cm (p = 0.02), pathologic response (p = 0.04), and multifocality (p = 0.01) by univariate, while only size >10 cm (p = 0.03) remained significant by multivariate analysis.

Metastasizing aneurysmal dermatofibroma initially diagnosed as angiosarcoma confirmed by CD63::PRKCD fusion gene detection with nanopore sequencing.

Dermatofibroma (DF) is a benign tumor that forms pedunculated lesions ranging in size from a few millimeters to 2 cm, usually affecting the extremities and trunks of young adults. Histopathologically, DF is characterized by the storiform proliferation of monomorphic fibroblast-like spindle cells. In addition to neoplastic cells, secondary elements such as foamy histiocytes, Touton-type giant cells, lymphoplasmacytes, and epidermal hyperplasia are characteristic histological features. Several histological variants, including atypical, cellular, aneurysmal, and lipidized variants, have been reported; cases with variant histologies are sometimes misdiagnosed as sarcomas. We present a case of metastasizing aneurysmal DF that was initially diagnosed as an angiosarcoma on biopsy. A 26-year-old woman was referred to our hospital with a gradually enlarging subcutaneous mass in her lower left leg. Positron emission tomography-computed tomography revealed high fluorodeoxyglucose uptake not only in the tumor but also in the left inguinal region. On biopsy, ERG and CD31-positive atypical spindle cells proliferated in slit-like spaces with extravasation, leading to the diagnosis of angiosarcoma. Histology of the wide-resection specimen was consistent with DF, and lymph node metastasis was also observed. Nanopore DNA sequencing detected CD63::PRKCD fusion and copy number gain, although CD63 was not included in the target region of adaptive sampling. This report highlights the importance of recognizing the unusual clinical, radiological, and pathological features of DF to avoid misdiagnosis, and the potential diagnostic utility of nanopore sequencer.

Synchronous Double Primary Angiosarcoma Originating from the Stomach and Rectum: A Case Report and a Literature Review.

Angiosarcomas originating from the gastrointestinal tract are rare but highly aggressive tumors with poor prognosis. These tumors can be misdiagnosed as benign and malignant gastrointestinal tract lesions. The definitive histological diagnosis of angiosarcomasis made by pathologists based on immunohistochemical analysis demonstrating cluster of differentiation 31 (CD31), factor VIII-related antigen (FVIIIRAg), erythroblast transformation specific related gene (ERG), and cluster of differentiation 34 (CD34). Angiosarcomas are treated with a single or multimodality approach that may include resection, radiotherapy, chemotherapy, and palliative care, depending on the stage of disease and the condition of the patient. No matter the treatment option, metastasis and death rates are substantially highin patients with angiosarcoma. In this context, a 59-year-old male with synchronous double primary angiosarcoma arising from the gastric and rectum who presented with the complaint of abdominal pain and distention to the outpatient clinic is presented in this case report, along with a brief literature review.

Pathological findings of mammary gland carcinoma and hemangiosarcoma cases in two African wild dogs (Lycaon pictus).

There are few studies on diseases affecting endangered African wild dogs. We report our findings on malignant tumors in two African wild dogs. Case 1 was a 6-year-old intact female diagnosed with inflammatory mammary carcinoma with pulmonary metastasis. Case 2 was an 11-year-old male diagnosed with primary hemangiosarcoma of the left atrial coronary sulcus with metastasis to multiple organs. Additionally, the tumor had grown through the cardiac wall, causing cardiac tamponade. The identification of disease incidence trends provides important information which will allow for the early detection and treatment of malignant tumors, and aid in the conservation of this species.

Brain radiotherapy and anlotinib control primary cardiac angiosarcoma with metastases: A case report.

RATIONALE: Primary cardiac angiosarcoma (PCA) is a rare and fatal disease with a poor prognosis. Whether the survival of PCA patients can be prolonged with additional treatment following complete surgical excision is controversial. PATIENT CONCERNS: In this case study, a 52-year-old male complained of chest tightness and pain for 7 days before admission into the hospital. Subsequently, he revisited the hospital because of dizziness and headache. DIAGNOSES: Initially, the patient was diagnosed with PCA in the right atrium by thoracic computed tomography (CT). Palliative resection identified brain, lung, and liver metastases. INTERVENTION: The patient accepted multimodal combination therapy, including first-line chemotherapy and then second-line anlotinib concurrent with brain radiotherapy and immunotherapy. OUTCOME: Although anlotinib combined with brain radiotherapy controlled the growth of intracranial lesions, progression-free survival (PFS) was only 5 months, and the overall survival (OS) was only 12 months. LESSON: The treatment for metastatic PCA needs an in-depth exploration.

The complete Kaposi sarcoma-associated herpesvirus genome induces early-onset, metastatic angiosarcoma in transgenic mice.

Kaposi sarcoma (KS) is the most common cancer in persons living with HIV. It is caused by KS-associated herpesvirus (KSHV). There exists no animal model for KS. Pronuclear injection of the 170,000-bp viral genome induces early-onset, aggressive angiosarcoma in transgenic mice. The tumors are histopathologically indistinguishable from human KS. As in human KS, all tumor cells express the viral latency-associated nuclear antigen (LANA). The tumors transcribe most viral genes, whereas endothelial cells in other organs only transcribe the viral latent genes. The tumor cells are of endothelial lineage and exhibit the same molecular pattern of pathway activation as KS, namely phosphatidylinositol 3-kinase (PI3K)/Akt/mTOR, interleukin-10 (IL-10), and vascular endothelial growth factor (VEGF). The KSHV-induced tumors are more aggressive than Ha-ras-induced angiosarcomas. Overall survival is increased by prophylactic ganciclovir. Thus, whole-virus KSHV-transgenic mice represent an accurate model for KS and open the door for the genetic dissection of KS pathogenesis and evaluation of therapies, including vaccines.

Clinical recommendations for treatment of localized angiosarcoma: A consensus paper by the Italian Sarcoma Group.

Angiosarcoma (AS) represents a rare and aggressive vascular sarcoma, posing distinct challenges in clinical management compared to other sarcomas. While the current European Society of Medical Oncology (ESMO) clinical practice guidelines for sarcoma treatment are applicable to AS, its unique aggressiveness and diverse tumor presentations necessitate dedicated and detailed clinical recommendations, which are currently lacking. Notably, considerations regarding surgical extent, radiation therapy (RT), and neoadjuvant/adjuvant chemotherapy vary significantly in localized disease, depending on each different site of onset. Indeed, AS are one of the sarcoma types most sensitive to cytotoxic chemotherapy. Despite this, uncertainties persist regarding optimal management across different clinical presentations, highlighting the need for further investigation through clinical trials. The Italian Sarcoma Group (ISG) organized a consensus meeting on April 1st, 2023, in Castel San Pietro, Italy, bringing together Italian sarcoma experts from several disciplines and patient representatives from "Sofia nel Cuore Onlus" and the ISG patient advocacy working group. The objective was to develop specific clinical recommendations for managing localized AS within the existing framework of sarcoma clinical practice guidelines, accounting for potential practice variations among ISG institutions. The aim was to try to standardize and harmonize clinical practices, or at least highlight the open questions in the local management of the disease, to define the best evidence-based practice for the optimal approach of localized AS and generate the recommendations presented herein.