Vasculogenic Mesenchymal Tumor: A Clinicopathologic and Molecular Study of 55 Cases of a Distinctive Neoplasm Originating From Mediastinal Yolk Sac Tumor and an Occasional Precursor to Angiosarcoma.

We report 55 postchemotherapy resections of primary nonseminomatous mediastinal germ cell tumors with prominent vasculogenic features showing the formation of rudimentary to well-developed neoplastic vessels within primitive mesenchyme. These cases represented 25% of a cohort of 221 such specimens. The patients were 19 to 49 years old (mean, 28 y) and 98% had serological evidence of yolk sac tumor. The vasculogenic lesions, felt to represent a neoplastic reiteration of embryonic vasculogenesis in the splanchnic mesoderm of the yolk sac, were further subdivided into teratoma with vasculogenic stroma (n=9), vasculogenic mesenchymal tumor (VMT) (n=42, further classified into low grade [n=24] and high grade [n=18]), and angiosarcoma (n=4). The distinction of teratoma with vasculogenic stroma from VMT was based solely on the greater extent of VMT (exceeding 1 low power [×4 objective] microscopic field), with both categories showing a spectrum of vessels lined by atypical endothelium in a nonendothelial neoplastic stroma that often also generated vascular walls comprised of atypical smooth muscle. The angiosarcomas showed stratification of highly atypical endothelial cells or anastomosing vessels lined by nonstratified but cytologically similar endothelium. Immunohistochemical studies supported the generation of neoplastic vessels from the tumor stroma, most commonly by the development of stromal clefts showing reactivity for podoplanin, CD34, and occasionally ERG, followed by the gradual development from the clefts of thin-walled vessels that later became encircled by stromal cells showing smooth muscle differentiation by immunohistochemistry. Occasionally, round collections of stromal erythrocytes became surrounded by stromal cells to generate blood vessels. Fluorescence in situ hybridization showed chromosome 12p copy number increase in both the endothelial component and stromal component in 8/9 VMT cases and in 1/1 angiosarcoma. On follow-up, no patient with teratoma with vasculogenic stroma had evidence of a subsequent vascular tumor or sarcoma, whereas 8 of the 35 (23%) patients with VMTs (2 low grade and 6 high grade) and meaningful follow-up developed sarcoma (1 angiosarcoma, 2 rhabdomyosarcomas, and 5 not further characterized). The difference between low-grade and high-grade tumors was of borderline significance (P=0.058). Two of the 4 patients with angiosarcoma died of metastatic angiosarcoma, with the other 2 disease-free at 6.8 and 7 years. Compared with the 165 patients with follow-up and no vasculogenic lesions, there was a highly significant (P=4.3×10-5) association of any vasculogenic lesion with sarcomatoid tumors during the clinical course of VMT patients. In addition, 5/46 patients with follow-up and vasculogenic lesions (11%) died of either leukemia or myelodysplastic syndrome compared with 2 of 166 (1%) lacking them (P=0.0012). Three of the 5 patients had identifiable immature hematopoietic cells within their vasculogenic lesions, but 4 other VMT patients with these did not develop leukemia or myelodysplasia. We conclude: (1) vasculogenic lesions are frequent in postchemotherapy resections of primary mediastinal germ cell tumors with yolk sac tumor components; (2) they mostly consist of neoplastic vessels in a stroma that also generates neoplastic vascular walls of smooth muscle; (3) VMTs are associated with an increased incidence of sarcomas, even though most vasculogenic lesions in this context do not meet criteria for angiosarcoma; (4) the presence of vasculogenic lesions in postchemotherapy resections of primary mediastinal germ cell tumors place patients at increased risk for leukemia or myelodysplasia.

Angiomatosis of the breast: a clinicopathological and immunophenotypical characterisation of seven cases.

AIMS: Mammary angiomatosis is a rare, benign vascular lesion that morphologically mimics low-grade angiosarcoma (LGAS). To date, only occasional reports of this entity have been published, none of which included analysis by immunohistochemistry. The purpose of this study was to further characterise mammary angiomatosis by clinical, histological, and immunohistochemical means while emphasising distinguishing features from LGAS. METHODS: Seven cases of primary mammary angiomatosis were evaluated. For one patient, a subsequent recurrence was also evaluated. RESULTS: All patients were female with a median age at presentation of 51 years (range: 19-58 years). The most common clinical presentation was that of a palpable abnormality or mass (5/8) and the median primary tumour size was 3.1 cm (range: 2-9 cm). Of the six patients with follow-up, one developed a recurrence 6 years after initial presentation. Histologically, all cases were composed of variably sized ectatic, thin-walled vessels lined by flat normochromic endothelium diffusely infiltrating mammary stroma. Where present, lesional vessels infiltrated between and around terminal duct lobular units but not into individual intralobular stroma. Most cases (6/8) showed a combination of lymphatic-appearing and haemangiomatous-appearing vessels. Lymphatic-appearing vessels were D2-40 positive in all but one case. D2-40 was negative or weak in haemangiomatous-appearing vessels. All lesional vessels were CD31 positive. Ki-67 indices were <1% in all but one case (5%). CONCLUSIONS: Mammary angiomatosis is a rare vascular lesion that shares clinical, morphological and immunohistochemical features with LGAS; however, certain key traits make the distinction possible.

Primary cardiac epithelioid angiosarcoma with frond-like features: a rare and ominous radiological mimicker of benign cardiac tumors.

Most primary cardiac tumors are benign neoplasms, which generally can be differentiated from malignant neoplasms via certain radiological features. We present briefly a case of a 26-year-old man undergoing resection of a right atrial mass that based on preceding radiologic findings represent a myxoma. After pathologic examination, the lesion was determined to be an epithelioid angiosarcoma with unique frond-like architecture and multiple pedicular attachments to the atrial wall.

Primary angiosarcoma of the femoral artery in patient with kidney and liver polycystosis and multiple arterial aneurysms: report of the case and review of the literature.

The association between kidney and liver polycystosis and arterial aneurysms is well documented. However, it remains unclear whether these patients are at increased risk of malignant transformation. In this article, we describe a case of a primary angiosarcoma of the femoral artery with metastatic spread into the lungs and hilar lymph node arising in a 74-year-old man with kidney and liver polycystosis and multiple arterial aneurysms.

Primary angiosarcoma arising in an angiomyolipoma of the kidney: case report and literature review.

BACKGROUND: Primary angiosarcoma of the kidney is a rare and aggressive malignant tumor presenting with a recognizable vascular differentiation. Its prognosis is fatal and the pathogenesis remains unclear. Renal angiomyolipoma is a relatively infrequent renal cortical neoplasm and is composed of variable proportions of adipose tissue, spindle cells, epithelioid smooth muscle cells and abnormal thick-walled blood vessels. CASE PRESENTATION: Here, we reported a case in which a 64-year-old woman presenting with the chief complaint of a progressively enlarged mass in the left abdomen. Abdominal computed tomography confirmed presence of a tumor measuring 18 cm × 11 cm in the left posterior renal fascia. Microscopic examination and immunohistochemical staining confirmed co-existence of angiomyolipoma and angiosarcoma. Furthermore, the two components interspersed with each other and there were transitional zones between them. CONCLUSIONS: In this case, we described for the first time a primary renal angiosarcoma possibly arising in a pre-existing angiomyolipoma of the kidney.

Unusual Neuroendocrine Differentiation in a Small Round Cell Angiosarcoma: A Potential Histologic Mimicker of Superficial Ewing Sarcoma.

Neuroendocrine differentiation or aberrant expression of neuroendocrine markers is very uncommon in angiosarcomas (AS) and creates a challenging differential diagnosis with other superficial or soft tissue tumors. Herein, we report a new case of superficial AS presenting as a tumor lesion on the little finger of the right hand of a 52-year-old man. The tumor displayed CD56, chromogranin-A, and synaptophysin immunoreactivity. Tumor cells were positive for vascular markers (CD31, FLI1, ERG, D2-40, VE-cadherin, VEGR1,2, and 3), CD99, and EMA, but were negative for S100, CK (AE1/AE3), CK20, polyomavirus, and myogenic (desmin and myogenin) and melanocyte markers (melan-A and HMB45). Ki67 immunostains indicated high proliferative activity (>50%). The whole-body computed tomography did not reveal distant disease. The initial assessment considered several tumor subtypes as possible histological diagnoses, including Ewing sarcoma, Ewing-like sarcoma, Merkel cell carcinoma, and undifferentiated "small round cell sarcoma". Fluorescence in situ hybridization analysis was negative for EWSR1 translocation and molecular analysis failed to detect any EWSR1, CIC, SYT or BCOR rearrangement. As a follow-up investigation, we tested 17 cutaneous/superficial AS for neuroendocrine markers; however, only one of these showed focal CD56 and synaptophysin expression. In conclusion, the present findings indicate that neuroendocrine differentiation is a very infrequent feature in AS. We report an AS of the finger with an uncommon histological appearance and immunohistochemical profile: predominant round cell tumor proliferation and neuroendocrine differentiation. Pathologists should be aware of these potential histological and immunohistochemical pitfalls in AS.

Cutaneous angiosarcoma: a current update.

Cutaneous angiosarcoma (cAS) is a rare malignant neoplasm with variable clinical presentation. Although a distinct vascular tumour, cAS shares many overlapping histopathological features with other vasoformative and epithelioid tumours or 'mimickers'. cAS shows aggressive behaviour and carries a grave prognosis, thus early diagnosis is of paramount importance to achieve the best possible outcomes. Recently, several genetic studies were conducted leading to the identification of novel molecular targets in the treatment of cAS. Herein, we present a comprehensive review of cAS with discussion of its clinical, histopathological and molecular aspects, the differential diagnosis, as well as current therapies including ongoing clinical trials.

Cutaneous Malignant Vascular Neoplasms.

Accurate diagnosis of cutaneous malignant vascular tumors, including angiosarcoma and epithelioid hemangioendothelioma, is critical for determination of appropriate clinical management and prognosis. Although there have been significant advances in understanding genetic aspects of cutaneous vascular biology, differential diagnosis of malignant vascular tumor involving skin and superficial soft tissue is a frequent source of difficulty. This brief overview highlights the clinicopathologic features of primary and secondary cutaneous angiosarcoma and epithelioid hemangioendothelioma and also provides a short summary of newer molecular data.

Cardiac angiosarcoma: histopathologic, immunohistochemical, and cytogenetic analysis of 10 cases.

Angiosarcoma (AS) is the most common cardiac sarcoma with differentiation, and is poorly characterized from a molecular genetic standpoint. Prognosis remains poor, owing to several factors including aggressive tumor biology, poor response to adjuvant therapy, and lack of targeted therapy. The clinical, pathologic and molecular cytogenetic features were studied in ten cardiac AS surgically resected at Mayo Clinic (1994-2015) using a whole-genome, single-nucleotide polymorphism-based platform (OncoScan). Mean patient age was 47.8 years, male/female ratio was 1:1.5, and overall median survival was 5.2 months. The most common location was the right atrium (n=7), with one case each occurring in the epicardium, pericardium, and right ventricle. No patients had received thoracic irradiation. The most common morphology was spindle cell (n=8), with one case each of epithelioid and biphasic. ERG was the most sensitive vascular marker, with diffuse immunoreactivity in all cases. Several recurrent (present in at least 3 cases) aberrations were identified, including trisomies in chromosomes 4, 8, 11, 17, 20, as well as 1q+, and homozygous deletion of CDKN2. Patients who received adjuvant therapy had longer overall survival than those who did not (median 13.4 vs 3.2 months; P=.0283). There were no significant associations between tumor location, histology, immunohistochemical findings, cytogenetic profile, and clinical outcome; however, there was a trend towards improved overall survival in patients with tumors harboring 1q+(median 31.8 vs 3.7 months, P=.06). This study confirms recurrent cytogenetic aberrations in cardiac AS, some of which may have prognostic or predictive implications.

Primary splenic angiosarcoma with liver metastasis: A case report and literature review.

Primary splenic angiosarcoma (PSA) is an unusual and highly malignant vascular tumour with a high rate of metastatic. Moreover, the research on prognosis of the disease is poor. The epidemiology, etiology, clinical diagnosis and treatment of the disease remain challenging, because case reports of the disease are few in number. In accordance with other malignant tumors, PSA is very aggressive, and the majority of patients in which this disease is found are at an advanced stage. Almost all patients die within 12 mo of diagnosis irrespective of treatment. We report here a woman who had complained of upper bellyache and anorexia for 10 d. Magnetic resonance imaging showed enlargement of the spleen with multiple heterogeneous masses in the lower pole of the spleen. A hand-assisted laparoscopic splenectomy was performed which allowed histopathologic diagnosis. The patient was diagnosed with PSA and liver metastasis, and succumbed to the disease 35 d after surgery. The literature was finished combined with the clinical features, diagnosis and management of PSA.

Recurrent CIC Gene Abnormalities in Angiosarcomas: A Molecular Study of 120 Cases With Concurrent Investigation of PLCG1, KDR, MYC, and FLT4 Gene Alterations.

Angiosarcoma (AS) is a rare sarcoma subtype showing considerable clinicopathologic and genetic heterogeneity. Most radiation-induced AS show MYC gene amplifications, with a subset of cases harboring KDR, PTPRB, and PLCG1 mutations. Despite recent advances, the genetic abnormalities of most primary AS remain undefined. Whole-transcriptome sequencing was initiated in 2 index cases of primary soft tissue AS with epithelioid morphology occurring in young adults for novel gene discovery. The candidate abnormalities were validated and then screened by targeted sequencing and fluorescence in situ hybridization in a large cohort of 120 well-characterized AS cases. Findings were subsequently correlated with the status of KDR, PLCG1, MYC, and FLT4 gene abnormalities. The clinicopathologic relevance and prognostic significance of these genetic changes were analyzed by statistical methods. Concurrent CIC mutations and CIC rearrangements were identified in both index cases, with a CIC-LEUTX fusion detected in 1 case. Upon screening, an additional visceral AS in a young adult had a complex CIC rearrangement, whereas 6 others harbored only CIC mutations. All 3 CIC-rearranged AS cases lacked vasoformation and had a solid growth of round, epithelioid to rhabdoid cells, showing immunoreactivity for CD31 and Ets-related gene and sharing a transcriptional signature with other round cell sarcomas, including CIC-rearranged tumors. Overall, CIC abnormalities occurred in 9% (9/98) of cases, affecting younger patients with primary AS, with an inferior disease-free survival. In contrast, PLCG1 and KDR mutations occurred in both primary and secondary AS cases, accounting for 9.5% and 7%, respectively, with a predilection for breast and bone/viscera location, regardless of MYC status. MYC amplification was present in most secondary AS related to breast cancer (91%) compared with other causes (25%) or primary AS (7%). FLT4-amplified AS lacked PLCG1/KDR mutations, occurring predominantly in MYC-amplified population, and showed poor prognosis.

Angiosarcoma (Stewart-Treves syndrome) in postmastectomy patients: report of 10 cases and review of literature.

AIMS: To study the clinicopathologic features of Stewart-Treves syndrome (STS) in postmastectomy patients including the epidemiology, presentation, morphology, differentiation, pathogenesis and therapeutic options. METHODS AND RESULTS: Ten cases of STS in postmastectomy patients were retrospectively identified in our archives, and immunohistochemistry for CD34, CD31, D2-40, HHV-8, CK, EMA and Ki-67 was performed. All ten patients presented with lymphedema after mastectomy as the first sign. Physical examination revealed multiple raised, pinkish-red papulo-vesicular lesions or ulceration as the early evidence of tumor in the field where radiation therapy was introduced. Microscopic examination revealed infiltrative proliferation of vessels and the heteromorphic tumor cells expressed CD34, CD31 and D2-40. Despite the various treatment modalities, 5 patients died in an average of 19 months, 4 patients survived to the last follow-up (9-31 months), and 1 patient got lost. CONCLUSIONS: STS is a fatal complication of postmastectomy lymphedema. Patients with STS have very poor prognosis. The key to improve patient's survival is the early diagnosis through a high alert of this disease by primary care physicians and comprehensive physical examination of patients with pertinent history and suspicious clinical presentations followed by prompt biopsy for definitive diagnosis.

Case report of primary splenic angiosarcoma with hepatic metastases.

Primary splenic angiosarcoma (PSA) is the most unusual type of malignancy with early multifocal metastasis through hematogenous spread. PSA is generally believed to originate from splenic sinusoidal vascular endothelium with a high rate of metastasis and to have a poor prognosis. Its etiology and pathogenetic mechanisms have not yet been clearly described. Thus far, only approximately 200 cases have been reported. PSA has variable symptomatology with the potential to present with life-threatening complications. The diagnosis of PSA is challenging; and often late. PSA should be considered in the differential diagnosis of patients with splenomegaly and anemia of unknown etiology. Surgical treatment with splenectomy is considered the only curative intervention for potential long-term disease-free survival. Early diagnosis and treatment are very important. It is important that clinical doctors improve the understanding of PSA. Herein, we report one rare case of PSA with hepatic metastases, along with a review of the current literature.

Angiosarcoma Arising in Chronic Expanding Hematoma: Five Cases of an Underrecognized Association.

Little is known about the etiology or pathogenesis of angiosarcoma (AS). We describe a series of 5 cases of AS arising in chronic expanding hematomas. Inclusion criteria were the presence of a hematoma of at least 1-year duration and a thick fibrous wall surrounding the hematoma. Patients were 4 men and 1 woman; ages ranged from 43 to 71 years. Locations were the thigh (3), chest wall (1), and pelvic soft tissue involving the ischial bone (1). Hematoma duration ranged from 2 to 25 years. All cases had large cystic hematomas >10 cm; 2 had prior radiation. Thick fibrous walls surrounded the hematomas, with foci of hemosiderin and foamy histiocytes. Wall thickness ranged from 0.2 to 1.0 cm and varied within lesions. All AS were epithelioid, and in 3 cases the tumor invaded through the cyst wall. Immunoreactive nuclear c-myc was noted in 3/3 cases available for testing. Follow-up disclosed 4 patients developed metastatic disease, 3 of whom died of disease, 4, 8, and 15 months after diagnosis; the fourth patient is alive without disease after chemotherapy at 59 months. One patient without metastases is alive without disease 18 months after diagnosis; this tumor was confined to the cyst without penetration through the wall. We identified 4 similar cases in the literature, 3 as individual case reports (all epithelioid AS), and 1 as part of a series of AS. To our knowledge, this is the first series of AS arising in chronic expanding hematomas. Recognition of this unusual complication should alert clinicians to provide periodic clinical follow-up to these patients and to biopsy any case with sudden or uncontrolled enlargement. We recommend that excised chronic hematomas be well sampled histologically to search for AS and, if identified, to determine its extent and invasiveness.

Primary eyelid angiosarcoma in a Chinese patient.

PURPOSE: To describe a case of primary eyelid angiosarcoma and review the literature to emphasize aware of this rare disease. CASE REPORT: We report a further case which is the first Chinese primary eyelid angiosarcoma in the literature. A 76-year-old woman presented with a 6-month history of a painless lesion on her left eyelid. The patient finally proved to be angiosarcoma on histopathologic and be treated with complete surgical excision with a frozen section margin control. With a 6 months follow-up, we haven't found any symptoms of recurrence or metastasis. CONCLUSIONS: Cutaneous angiosarcoma with eyelid is a rare, soft-tissue sarcoma of endothelial cell origin that is aggressive malignancy and has a poor prognosis. In our case report, the patient was treated with complete surgical excision with a frozen section margin control, and a 6 months follow-up, we haven't found any symptoms of recurrence or metastasis.

Intimal sarcoma of the abdominal aorta and common iliac arteries presenting as epithelioid angiosarcoma of the skin: a case report.

Intimal sarcoma (IS) is the most common type of sarcoma of the aorta. IS tumor emboli can involve various organs, including the skin. However, a limited number of IS cases with an initial presentation of skin metastasis has been reported. Cutaneous metastasis as a form of epithelioid angiosarcoma (EAS) has not been well described. Herein, we present a 61-year-old Japanese man with an initial presentation of EAS of the skin, followed by multiple metastases to the skin as a form of EAS prior to detection of IS of the infrarenal aorta and common iliac arteries. In our case, the IS was CD31 and cytokeratin positive but did not express CD34 and factor VIII-related antigen. The EASs in our case exhibited diffuse CD31 expression, and focal factor VIII-related antigen and cytokeratin expression were observed throughout the tumor, including the neoplastic vascular structure; CD34 expression was not identifiable. IS metastasis to the skin has been documented as a form of angiosarcoma. However, IS metastasis has not been well described as a form of EAS. Our case could prove a morphological change from IS to EAS. Given the rarity of primary cutaneous EAS, it is recommended that primary sites other than the skin should be thoroughly investigated when EAS of the skin is encountered.

Primary hepatic angiosarcoma: A report of two cases and literature review.

Primary hepatic angiosarcoma (PHA) is a rare malignancy that carries a poor prognosis. Of 1500 patients who underwent hepatectomy for primary hepatic tumors between 1994 and 2013 at our center, two patients were pathologically diagnosed with PHA. Clinical characteristics, treatment modalities, and outcomes of the two patients were collected and analyzed. Both patients underwent hepatectomy and had a postoperative survival time of 8 and 16 mo, respectively. A search of PubMed yielded eight references reporting 35 cases of PHA published between 2004 and 2013. On the basis of the presented cases and review of the literature, we endorse complete surgical resection as the mainstay definitive treatment of PHA, with adjuvant postoperative chemotherapy potentially improving survival. Palliative chemotherapy is an option in advanced hepatic angiosarcoma.