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.

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.

Primary cardiac angiosarcoma: Imaging characterization.

This case report describes a 35-year-old female patient who presented with palpitations and shortness of breath. Imaging findings suggested a cardiac tumor, histopathology confirmed primary cardiac angiosarcoma. This tumor is highly aggressive, usually occurs in the right atrium, lacks specificity in clinical presentation, is prone to early metastasis, and has a poor prognosis. Echocardiography is the method of choice for early detection and is important in assessing tumor size, location, mode of attachment and whether cardiac function is impaired.

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.

Radiotherapy combined with anti-PD-1 and TKI for primary cardiac angiosarcoma considering the joint assessment of TLSs and PD-L1: a case report.

BACKGROUND: Primary cardiac angiosarcoma(PCA) has a low incidence rate and poor prognosis. Currently, no unified clinical treatment standards are available. CASE PRESENTATION: We report the case of a 48-year-old man presenting chest tightness, breathlessness, and dyspnea. Imaging and postoperative histopathologic studies confirmed PCA and that the tumor had invaded the entire right atrium. The patient developed progressive disease (PD) during postoperative radiotherapy. We used immunotherapy combined with targeted therapy based on the results of molecular profile and evaluation of tertiary lymphoid structures (TLSs) and programmed cell death-ligand 1 (PD-L1). After treatment, the metastatic lymph nodes of the patient were reduced to a certain extent, indicating that combination therapy was effective. CONCLUSION: To the best of our knowledge, this is the first report of radiotherapy combined with anti-PD-1 and tyrosine kinase inhibitors(TKI) for PCA. In addition, this is the first report on immunotherapy for PCA based on new evaluation methods, including TLSs, PD-L1, and genomic profile.

Primary splenic angiosarcoma: a case series of a rare oncological entity and diagnostic challenge.

BACKGROUND AND PURPOSE: Primary angiosarcoma of the spleen (PAS), an exceptionally rare and aggressive neoplasm with high metastatic risk (70%-85%), is frequently diagnosed in an advanced or metastatic stage. It presents diagnostic challenges due to its nonspecific symptomatology and resemblance to benign vascular lesions in various imaging modalities. PATIENTS AND METHODS: This case series aims to clarify the diagnostic difficulties by comparing imaging characteristics (CT-scan, MRI, and [18F]FDG-PET/CT) as well as pathological findings of three PAS cases diagnosed in different stages of the diseases (localized, metastatic, and metastatic with organ failure). Furthermore, a brief review on diagnostic and therapeutic features is included. RESULTS AND INTERPRETATION: We suggest [18F]FDG-PET/CT as a differentiating tool between benign and malignant splenic lesions and propose a flowchart of a diagnostic algorithm for PAS. For treatment, we advocate for early splenectomy and when systemic therapy is warranted, paclitaxel emerges as a viable first-line option. While it is crucial to acknowledge that further trial data is required to evaluate the efficacy of emerging treatment regimens, designing and conducting trials for PAS is challenging given its scarcity and aggressive behavior. Therefore case reporting remains important.

Obstructive cardiac myxosarcoma of the right ventricular outflow tract with pulmonary embolism and concurrent right atrial hemangiosarcoma in a dog.

A 13-year-old spayed female rottweiler crossbreed dog was presented with an 8-day history of abnormal gait and collapse associated with excitement or physical activity. A cardiac gallop was noticed on thoracic auscultation, and a 1st-degree atrioventricular block and sinus tachycardia were noted on an electrocardiogram. Echocardiography identified a hypoechoic, irregularly marginated luminal mass in the right ventricle at the level of the pulmonic valves. Postmortem gross examination confirmed the presence of a soft, polypoid, and botryoid mass (9 × 3 × 3 cm) with a smooth and glistening surface attached to the endocardium of the right ventricular outflow tract and extending to the pulmonary artery. The histological findings were consistent with the diagnosis of myxosarcoma with pulmonary embolism. In addition, the dog in this report had a right atrial hemangiosarcoma and a cutaneous hemangioma unrelated to her clinical findings. Key clinical message: Cardiac myxosarcomas are very rare neoplasms in dogs and concomitant primary heart tumors of different histogenesis are even rarer in dogs. To the authors' knowledge, this is the first report of coexistent myxosarcoma and hemangiosarcoma in the heart of a dog. Cardiac myxosarcomas should be considered in the differential diagnosis of intracavitary heart masses associated with signs of cardiac obstruction and failure.

Myxosarcome cardiaque obstructif de la voie d'éjection du ventricule droit avec embolie pulmonaire et hémangiosarcome auriculaire droit concomitant chez un chien. Une chienne croisée rottweiler stérilisée âgée de 13 ans a été présentée avec une histoire de démarche anormale et d'effondrement associés à l'excitation ou à l'activité physique depuis 8 jours. Un galop cardiaque a été noté à l'auscultation thoracique, un bloc auriculo-ventriculaire du 1er degré et une tachycardie sinusale ont été notés à l'électrocardiogramme. L'échocardiographie a permis d'identifier une masse luminale hypoéchogène et irrégulièrement marginalisée dans le ventricule droit au niveau des valvules pulmonaires. L'examen macroscopique post-mortem a confirmé la présence d'une masse molle, polypoïde et botryoïde (9 × 3 × 3 cm) avec une surface lisse et brillante attachée à l'endocarde de la voie d'éjection du ventricule droit et s'étendant jusqu'à l'artère pulmonaire. Les résultats histologiques concordaient avec le diagnostic de myxosarcome avec embolie pulmonaire. De plus, la chienne dans ce rapport présentait un hémangiosarcome auriculaire droit et un hémangiome cutané sans rapport avec ses résultats cliniques.Message clinique clé :Les myxosarcomes cardiaques sont des néoplasmes très rares chez le chien et les tumeurs cardiaques primaires concomitantes d'histogenèse différente sont encore plus rares chez le chien. À la connaissance des auteurs, il s'agit du premier rapport de myxosarcome et d'hémangiosarcome coexistant dans le cœur d'un chien. Les myxosarcomes cardiaques doivent être pris en compte dans le diagnostic différentiel des masses cardiaques intracavitaires associées à des signes d'obstruction et d'insuffisance cardiaque.(Traduit par Dr Serge Messier).

Misdiagnosis of cutaneous epithelioid angiosarcoma as diabetic foot ulcer: a case study.

BACKGROUND: AS is a malignant tumor that originates from vascular endothelial cells and is known for a high rate of local recurrence and metastasis. CASE REPORT: A 48-year-old male presented with cutaneous epithelioid AS. Cutaneous AS of the foot is quite rare, especially in the absence of predisposing factors, and in this patient it was previously misdiagnosed as a DFU. CONCLUSION: Physicians should be aware of this rare presentation of cutaneous AS. The authors of the current report advise regular clinical reassessment of chronic ulcers and biopsies of nonhealing wounds, even when adequate wound treatment has been administered, with the goal of identifying ulcerated skin malignancies and preventing delay in providing appropriate treatment.

Unusual presentation and delayed diagnosis of cardiac angiosarcoma.

BACKGROUND: Primary cardiac angiosarcomas are very rare and present aggressively with high rates of metastasis. Given the poor prognosis, particularly once disease has spread, early diagnosis and multidisciplinary treatment is essential. CASE PRESENTATION: We present the case of a 46-year-old male who presented with chest pain, intermittent fevers, and dyspnea. Workup with computed tomography scan and transesophageal echocardiography demonstrated a right atrial pseudoaneurysm. Given the concern for rupture, the patient was taken to the operating room, where resection of the pseudoaneurysm and repair using a bovine pericardial patch was performed. Histopathology report initially demonstrated perivascular lymphocyte infiltrate. Six weeks later, the patient represented with chest pain and new word finding difficulty. Workup revealed multiple solid lung, pericardial, brain, and bone nodules. Eventual biopsy of a cardiophrenic nodule demonstrated angiosarcoma, and rereview of the original pathology slides confirmed the diagnosis of primary cardiac angiosarcoma. CONCLUSIONS: Primary cardiac angiosarcomas are often misdiagnosed given the rarity of these tumors, but early diagnosis and initiation of treatment is essential. The unique presentation of our case demonstrates that clinical suspicion for cardiac angiosarcoma should be maintained for spontaneous pseudoaneurysm originating from the right atrium.

Numerous multinucleated giant cells in cutaneous epithelioid angiosarcoma and pulmonary metastasis: A unique observation with potential diagnostic pitfalls.

The histopathologic diagnosis of poorly differentiated cutaneous angiosarcoma can be challenging. We report a case of cutaneous epithelioid angiosarcoma with numerous multinucleated giant cells (MGCs) developing pulmonary metastasis. A 79-year-old man presented with a red-purple plaque on the scalp. A skin biopsy revealed epithelioid cell proliferation, admixed with numerous MGCs, and background hemorrhage. Vascular spaces were focally present and lined by atypical endothelial cells, including MGCs. Immunohistochemically, tumor cells, including MGCs, were positive for CD31, D2-40, and ERG. The patient received radiation therapy and chemotherapy, after which a follow-up CT scan revealed symptomless pneumothorax and pulmonary metastases. The patient received palliative partial lung resection, and the specimen revealed histopathological and immunohistochemical features similar to the primary cutaneous lesion. Our report expands the morphologic spectrum of cutaneous epithelioid angiosarcoma. Cutaneous angiosarcoma is an aggressive neoplasm; thus, awareness of this rare manifestation is important.

Chalazion-mimicked eyelid angiosarcoma in a young Asian with good prognosis: a case report.

BACKGROUND: Angiosarcoma is an extremely rare malignant tumor. So far, only about 42 cases of angiosarcoma involving the eyelids have been reported. Eyelid angiosarcoma occurs more frequently in elderly Caucasian males and is prone to misdiagnosis. We present a case report in a young Asian male patient with eyelid angiosarcoma that was misdiagnosed as a chalazion. CASE PRESENTATION: A 46-year-old South Korean male with no underlying disease had a right lower lid mass. The lesion was initially misdiagnosed as a chalazion at a local clinic, but a diagnosis of eyelid angiosarcoma was made after the first biopsy trial. PET-CT was performed to ensure that there was no metastasis in the whole body. Surgical excision with enough surgical margin was used alone for treatment and reconstruction was performed with a tarsoconjunctival advancement flap (modified Hughes procedure), which helped ensure good cosmesis. No recurrence was observed 4 years and 5 months after the surgery. CONCLUSIONS: The current study presents the first case of chalazion-mimicked eyelid angiosarcoma in a young Asian male aged under 50 years. This case shows that even if a benign eyelid disease is suspected in a young patient, an incisional biopsy must be performed to confirm whether the lesion is malignant. Since the prognosis is good for the case of eyelid angiosarcoma, if there is no clear evidence of distal metastasis, surgical resection should be performed with an enough safety margin.

Primary angiosarcoma of the Pancreas - A case Report and review of the literature.

BACKGROUND: Angiosarcomas are malignant neoplasms that originate from endothelial cells. The symptoms exhibit a non-specific nature, and achieving a preoperative diagnosis is frequently challenging. They are seldom encountered in the abdomen, and their occurrence in the pancreas is even rarer. METHODS: Here we document a 67-year-old man with pancreatic angiosarcoma and analyse the literature to outline the clinicopathologic characteristics of this rare phenomenon. RESULTS: This patient with family history of pancreas cancer presented with abdominal pain, and the CT-scan revealed a 4 cm mass at the neck of the pancreas but CA19-9 was normal. Radiologic findings were unusual for ordinary pancreas cancer. Fine-needle aspiration biopsy through endoscopic ultrasound revealed "undifferentiated malignant cells for which the diagnosis of "carcinoma" was favoured. Total pancreatectomy, splenectomy and portal vein reconstruction were performed and epithelioid angiosarcoma were diagnosed. Despite an uneventful postoperative period, discharge on postoperative day 8 without any complications, as well as diligent post-discharge clinical care, the patient died 65 days postoperatively, attributed to the presence of extensive metastasis. A comprehensive literature search has identified a limited number of documented cases of primary pancreatic angiosarcoma, with only ten cases reported to date. CONCLUSIONS: Pancreatic angiosarcomas are very rare and prone to misdiagnosis. The formation of a more demarcated but high-grade tumour with necrosis is a feature that distinguishes angiosarcomas from ordinary carcinomas of this organ. Pathologic diagnosis is also highly challenging closely resembling undifferentiated carcinomas. Angiosarcomas are highly aggressive when they occur in the pancreas. Prompt diagnosis at an early stage is crucial as surgery with curative intent serves as the primary treatment approach.

Surgery with curative intent is the mainstay treatment for pancreatic angiosarcoma when diagnosed at an early stage.Oncological treatment options should be taken into consideration according to the follow-up data.Why does this paper matter?This article is important in that it is the most comprehensive review of the literature on pancreatic angiosarcoma, which is a very rare pathology, from the perspective of radiology, pathology and surgery.

Feline ventral abdominal wall angiosarcoma: haemangiosarcoma or lymphangiosarcoma? Clinical and pathological characteristics in nine cases.

OBJECTIVES: Angiosarcomas are rare malignant mesenchymal neoplasms of endothelial cell origin with a predilection to the ventral abdominal wall in cats. Larger case series describing this entity are lacking. METHODS: Two referral centre laboratory databases were searched for angiosarcoma of the ventral abdominal wall. Nine cases with a histological diagnosis were included. Immunohistochemistry (factor VIII and PROX-1 antibodies) was used to phenotype them as haemangiosarcoma or lymphangiosarcoma. RESULTS: All cats presented with a ventral abdominal mass, five of which were producing a serosanguinous discharge. Eight underwent tumour staging and pulmonary metastases were suspected in one cat (but not histologically confirmed). With histopathology alone, a diagnosis of angiosarcoma and lymphangiosarcoma was made in four and five cases, respectively. After immunohistochemistry, five cases had a haemangiosarcoma phenotype and four had a lymphangiosarcoma phenotype, including two cases of lymphangiosarcoma that were reclassified as hemangiosarcoma. Eight cats received treatment (either surgery with or without adjuvant therapies or medical management alone). Six cats were euthanased due to local disease progression. The median survival time for haemangiosarcoma was 166 days (range 137-381), and for lymphangiosarcoma it was 197 days (range 67-208). Two cats with haemangiosarcoma remained alive for a follow-up period of 329 and 580 days, respectively. CONCLUSIONS AND RELEVANCE: Feline ventral abdominal angiosarcomas are rare locally aggressive neoplasms. While histology often provides a diagnosis of angiosarcoma, immunohistochemistry is ultimately required to differentiate between haemangiosarcoma and lymphangiosarcoma phenotypes. Further studies are required to evaluate whether the different phenotypes have an impact on treatment response and outcome.

Angiosarcoma of gallbladder, a literature review.

BACKGROUND: Angiosarcoma of the gallbladder is a rare diagnostic entity rarely encountered by pathologists and has rarely been reported in literature. This review aimed to examine the clinicopathological features, immunohistochemistry, treatment, and outcomes of gallbladder angiosarcoma. METHODS: A search of the PubMed, Science Direct and Google Scholar was done with the search terms ("angiosarcoma" OR "angiosarcomas") AND ("gallbladder" OR "gallbladders"). Based on inclusion and exclusion criteria, only case reports could be used for this review. RESULT: 8 case reports were chosen in the end for analysis. The mean age of the patients at presentation was 65 years. It was most frequently observed in males. Abdominal pain and palpable mass were the most commonly reported symptoms. Cholelithiasis and anemia were also reported. On histopathology morphologically epithelioid appearance of angiosarcoma was evident. Cytokeratin (CK) AE1/AE3, Von willebrand factor, Factor VIII antigen, Vimentin, CD31 were positive. Meanwhile, UEA, CD34, CD117, S-100, Keratin, EMA, and CEA showed negative outcome. Surgery was the preferred method of treatment and a mean 10-months follow-up was done. CONCLUSION: Despite the unavailability of convincing data, histological and immunohistochemical analyses play a major role in the diagnosis of gallbladder angiosarcoma. Nevertheless, more comprehensive clinical studies are required to provide universal guidelines for the treatment and diagnosis of angiosarcoma of the gallbladder.

Acantholytic squamous cell carcinoma mimicking epithelioid angiosarcoma: A diagnostic challenge by cytology.

Squamous cell carcinoma (SCC) is the most common malignancy of the head and neck region. Most cases present little diagnostic difficulty on fine needle aspiration (FNA), but unusual variants can be problematic. The authors report a case of the acantholytic SCC of the oral cavity in a 36-year-old male. The FNA showed hypercellularity, with malignant cells arranged in isolation, loosely cohesive groups and a linear configuration. Such cells were round to elongated, with vesicular nuclei and prominent nucleoli. Cells possessed occasional intracytoplasmic vacuoles, misinterpreted on FNA to be vasoformative features as seen in malignant endothelial cells. The cytologic diagnosis was "positive for malignancy, suggestive of angiosarcoma". A total excision was performed and by histology, the tumor was diagnosed as acantholytic SCC. The malignant cells were positive by immunostaining for AE1/AE3, p40, p63 and vimentin, but negative for CD31, CD34 and ERG. The intracytoplasmic vacuoles were PAS- and mucin-negative and negative for the above antibodies. Testing for HPV (molecular and p16 immunostaining) was negative. This case highlights the diagnostic challenges on cytology when malignant acantholytic squamous cells show intracytoplasmic vacuoles, and stresses how immunohistochemistry is important for distinguishing acantholytic SCC from other mimics.

A case of a motor vehicle collision suspected as associated with development of angiosarcoma.

Trauma has been suspected as a factor leading to development of angiosarcoma, a malignant soft-tissue tumor. We conducted a forensic autopsy to investigate a putative relation between a motor vehicle collision and the driver's later death from angiosarcoma. A vehicle operated by a man in his 60 s collided with an oncoming vehicle at a curve. The victim noticed no injury at the scene. However, 45 days later, he was transferred to an emergency room with dyspnea and bloody sputum. After diagnosis of angiosarcoma, he died of respiratory failure 132 days later. The bereaved family speculated about a relation between the collision and angiosarcoma onset. At autopsy, tumor cells of the scalp had metastasized to the lung, pleura, liver, and spleen. Histopathological examinations revealed characteristic features of angiosarcoma with positive immune-staining for CD31, CD34, and factor VIII. When a person dies some time after a collision, it is designated as a delayed death. In such cases, the relevance of trauma to the person's death is often an issue of concern. Because the interval between trauma and angiosarcoma development was short, only 45 days, the angiosarcoma might be coincidental. Therefore, we rejected the relation. Forensic experts sometimes need to investigate such inquiries.