Popliteal Angiosarcoma after Bypass with Autologous Saphenous Vein

Angiosarcoma (AS) is a type of malignancy within sarcomas affecting soft tissue and bone. It presents a very heterogeneous distribution in the human body, and it can appear in multiple locations, from breast to liver or skin. The incidence of this type of tumor is low; however, it is aggressive and requires an early diagnosis to initiate the treatment as soon as possible. In the present article, we report the case of a male patient who was diagnosed with epithelioid AS of popliteal artery after an aneurysm popliteal surgery, as well as its treatment and evolution. This kind of tumors has controversial treatment and poor survival rates in the early years.

Successful management of steroid-resistant vascular tumors associated with the Kasabach-Merritt phenomenon using sirolimus

Vascular tumors associated with Kasabach-Merritt phenomenon (KMP) are life-threatening and the mortality is as high as 10-30%. Steroids are considered the primary choice for drug therapy. However, there are many steroid-resistant cases. In the present study, analyzed data are presented to support the use of sirolimus in clinical practise for the treatment of corticosteroid-resistant vascular tumors with KMP in eight infants between June 2015 and April 2017 in a single hospital. The time to initial response was 6.8 ± 2.7 days. The average stabilization time for the platelet count was 19.1 ± 8.5 days. At the time of publication, the average duration of sirolimus treatment was 14.1 ± 4.0 months, and the average time for sirolimus treatment as a single agent was 12.6 ± 4.2 months. The side-effects were tolerable and included oral ulcer, fever, pain, skin rash and transient ascension of serum transaminase and cholesterol. Our study indicated that sirolimus therapy is an effective and safe method for the treatment of corticosteroid resistant vascular tumors associated with KMP in infants.

Primary Intimal Sarcoma of the Aorta Associated With a Dacron Graft and Resulting in Arterial Rupture

Primary arterial neoplasms are rare lesions which have been most frequently associated with local or constitutional symptomatology, and with distal embolization. Perirenal aortic disruption with pseudoaneurysm formation due to an intimal sarcoma adjacent to a previously placed prosthetic graft is reported in a 66-year-old man. This case supports the premise that the presence of a vascular prosthesis might result in the induction of an arterial wall malignancy. This should be considered when an intraluminal mass is identified in the absence of other arterial pathology. Although the prognosis of these tumors is poor, their preoperative recognition may enhance treatment outcomes.

Ultrasound guided block of the saphenous neuroma following use of an AFO in a patient with paraplegia. A case report

The saphenous nerve is the terminal branch of the femoral nerve and a pure sensory nerve that provide sensation to medial leg. Injury to saphanous nerve following trauma or surgery of the knee can result in formation of a painful neuroma along its distribution. We present a case of saphenous neuroma following use of an ankle-foot orthosis (AFO) in a patient with paraplegia. A 36-year-old patient with paraplegia who was capable of walking independently with his AFO presented to our department with a 3-month history of pain in his left calf. Examination revealed tenderness, paresthesias and positive Tinel sign over the anteromedial aspect of the calf. Ultrasonographic examination of the painful area showed a mass with heterogenous echogenity which was consistent with a saphenous neuroma at the site where fastener band of AFO compressed to skin. We performed a nerve block with steroid and local anesthetic injection under ultrasound guidance to the neuroma. The patient reported pain relief following injection. The use of the AFO may cause a painful saphenous neuroma which is an unusual cause of extremity pain in patients with paraplegia. Ultrasound may be a beneficial diagnostic tool and a guidance for the therapeutic interventions in this condition.

Angiosarcoma arising in an arteriovenous fistula in a patient without kidney transplant

Angiosarcomas are relatively rare and account for only 1% of all sarcomas. They arise from endothelial cells of blood or lymph vessels. They are usually highly aggressive and long term outcome is poor with an overall 5-year survival rate of 10-20%. We report the case of a 80-year old man with an angiosarcoma arising in a non-functioning arteriovenous fistula. Angiosarcomas arising in an arteriovenous fistula are very rare and only eleven cases were found in the literature. In nine cases (82%) chronic immunosuppression, taken for renal transplant, was one of the causing factors. Our patient however did not receive a kidney transplant and was not on immunosuppressive therapy. Clinicians should be aware that an angiosarcoma can arise in an arteriovenous fistula even without chronic immunosuppression.

[Racemose hemangioma of the bronchial artery]

Racemose hemangioma of the bronchial arteries is a rare abnormality and is characterized by enlarged and convoluted bronchial arteries arranged segmentally along the longitudinal axis of bronchus. Primary racemose hemangioma may arise from inborn malformation, and secondary one may develop following primary inflammatory, stenosing or deforming diseases of the bronchus, the peribronchial tissues and the surrounding lung tissues. The symptom at onset is usually hemoptysis. Although the typical treatments have not been established, various treatments, like embolization or ligation of the bronchial arteries and surgical resection of the involved area of lung, were reported. However the term 'Racemose hemangioma' seems to be used only in Japan, so it is favorable to make a consensus of its definition among countries.

Vascular smooth muscle tumors: Review of the literature

Vascular smooth muscle tumors are very rare. They can be benign or malign. Intravascular leiomyomatosis is a benign neoplasm that extends through the veins and caries significant morbidity. Angioleiomyoma is a benign neoplasm of the extremities that caries minimal morbidity. Vascular leiomyosarcomas are malign neoplasms derived from vascular smooth cells. They are usually localized to the inferior vena cava, but can also arise from the pulmonary arteries or veins or other peripheral vessels. This study reviews literature for epidemiology, clinical presentation, diagnosis and management of patients with vascular smooth muscle tumors.

[Case of jugular foramen schwannoma associated with tuberous sclerosis]

We report a case of jugular foramen schwannoma associated with tuberous sclerosis. A 28-year-old female with tuberous sclerosis presented to Hikone Municipal Hospital with subacute onset of somnolence, ataxic gait and frequent vomiting. Her tuberous sclerosis was diagnosed at the age of 9, when she developed hydrocephalus caused by subependymal giant cell astrocytoma near the foramen of Monro, which was treated by surgical resection and VP shunt placement followed by radiation and chemotherapy. Brain MR images revealed a 3 cm enhancing mass extending from the left jugular foramen to the cerebellopontine cistern, accompanied by perifocal edema of the brain stem and cerebellar hemisphere. The tumor was partially removed via suboccipital craniotomy and histologically diagnosed as a schwannoma. After surgery her symptoms promptly improved and 4 months later she underwent additional stereotactic radiosurgery. No tumor regrowth has been observed at 94 months. Intracranial schwannoma complicating tuberous sclerosis is very rare. Only one other case has been reported in the literature.

A case of portal cavernoma--associated essential thrombocythemia

Portal cavernoma is a rare complication of portal vein thrombosis and may be a component of the myeloproliferative hematologic disorders. In the present case report, although the symptoms induced by portal hypertension and portal biliopathy had a concordant evolution with the portal cavernoma, the peripheral thrombocytosis and the medullar expression of essential thrombocythemia became relevant at 18 months.

Hepatocellular carcinoma with sarcomatous change arising after eradication of HCV via interferon therapy

A patient was diagnosed with chronic hepatitis C at the age of 63 years. He achieved eradication of HCV via interferon (IFN). Eight years after, a hepatocellular carcinoma (HCC) was detected and treated through transarterial embolization and percutaneous ethanol injection therapy. After about 1 year, a large hypovascular tumor was detected. This tumor was surgically resected and diagnosed as an HCC with sarcomatous change. This is the first case of an HCC with sarcomatous change arising after a sustained response to IFN therapy.

[A case of primary fibrosarcoma of the pulmonary artery]

A 38-year-old-man was admitted to our hospital complaining of exertional dyspnea. Chest radiography and CT showed a huge mass that completely occluded the left main pulmonary artery and spread into the right main pulmonary artery. The tumor was diagnosed as sarcoma by transbronchial biopsy. Radiation therapy obtained temporary partial response. He died of respiratory insufficiency after 14 months. The autopsy revealed primary pulmonary artery sarcoma: fibrosarcoma arising from the left pulmonary artery. To our knowledge, this is the first case report of fibrosarcoma of the pulmonary artery in Japan.

Intravascular lymphoma associated with haemophagocytic syndrome: a very rare entity in western countries

Intravascular lymphoma (IVL) is a rare and aggressive disorder, characterised by frequent cutaneous and neurological involvement and medullary infiltration. In rare cases particularly in Asia, IVL can be associated with haemophagocytic syndrome (IVL-HS). Here, we report the case of a 61-year-old Caucasian female who presented with IVL-HS. Bone marrow biopsy showed haemophagocytic features and medullary localisation of a diffuse large B-cell lymphoma. Liver biopsy showed exclusive sinusoidal infiltration by large B cells. Treatment by polychemotherapy associated with rituximab induced a rapid complete remission. Unfortunately, death occurred as a consequence of septic shock. Early recognition of IVL-HS by performing bone marrow biopsy is critical to start rapidly appropriate treatment. The role of rituximab in the management of IVL-HS remains to be established.

Angiosarcoma arising in an arteriovenous fistula site in a renal transplant patient: a case report and literature review

Angiosarcoma in the setting of immunosuppressed renal transplant recipients is exceedingly rare. In this report, we describe the occurrence of angiosarcoma arising at an arteriovenous fistula site of a 39-year-old renal transplant recipient that clinically mimicked a thrombosed aneurysm. These tumors are histologically high-grade and clinically aggressive malignancies. They have a predilection for arteriovenous fistula sites. The literature on this uncommon entity is reviewed and possible histogenesis is discussed.

Estrogen and progesterone expression of vessel walls with intravascular leiomyomatosis; discussion of histogenesis

We report seven cases of intravenous leiomyomatosis. Growth beyond the uterus occurred in two of the seven cases in the broad ligament. One 21-year-old patient is one of the youngest reported cases in the literature. Five patients had total abdominal hysterectomy with removal of the adnexa and two patients underwent myomectomy. One of the myomectomy cases had abdominal hysterectomy and bilateral salpingo-oophorectomy one year later due to recurrence. The other one was disease free six months after the operation. Vessel walls harboring intravascular tumor were investigated immunohistochemically for Factor VIII, CD 34, estrogen and progesterone receptors with the hope of making the histogenesis of intravenous leiomyomatosis clear. Immunohistochemical analyses of estrogen receptors, progesterone receptors, vimentin, desmin, smooth muscle actin, CD 10 and h-caldesmon were performed on intravascular tumor cells. Endothelial and subendothelial cells expressed none to scant, very weak progesterone and estrogen receptor positivity. Intravascular tumor cells showed weak (10%) to strong (70%) progesterone receptor positivity and weak (10%) to strong (60%) estrogen receptor positivity. These results do not support the hypothesis of a vessel wall origin for intravenous leiomyomatosis.

Susceptibility to vascular neoplasms but no increased susceptibility to renal carcinogenesis in Vhl knockout mice

The von Hippel-Lindau (VHL) tumor suppressor gene plays a prominent role in the development of renal cell carcinoma (RCC) in humans. VHL functions as a ubiquitin E3 ligase, controlling the stability of hypoxia inducible factor (HIF) and tumor angiogenesis. Alterations in this tumor suppressor gene are rarely observed in spontaneous or chemically induced RCC that arise in conventional strains of rodents and Vhl knockout mice (Vhl+/-) do not develop spontaneous RCC. We tested whether Vhl knockout mice exhibited increased susceptibility to renal carcinogenesis using the well-characterized renal carcinogen streptozotocin. No differences were observed between wild-type and Vhl+/- animals in the frequency or type of renal lesions induced by 50-200 mg/kg streptozotocin. Carcinogen-induced RCC that developed in Vhl heterozygotes and wild-type mice did not contain mutations in the wild-type Vhl, as determined by direct sequencing of the primary tumors. While Vhl+/- mice exhibited no increase in renal lesions in response to streptozotocin, heterozygous animals did develop vascular proliferative lesions of the liver, uterus, ovary, spleen and heart. These lesions, ranging from angiectasis to hemangiosarcoma, were most prominent in the livers of Vhl+/- mice, where they were found in high incidence and high multiplicity. Wild-type mice developed a low-frequency of liver angiectasis (7-15%) only at the highest doses of carcinogen used (150 and 200 mg/kg, respectively) while Vhl+/- mice exhibited angiectasis, hemangioma and hemangiosarcomas with a frequency ranging from 19 to 46% at 50-200 mg/kg streptozotocin. Untreated Vhl+/- mice had a spontaneous incidence of hepatic vascular lesions of 21%. Furthermore, vascular lesions of the uterus, ovary, spleen and heart were observed only in Vhl+/- mice, with an incidence of (5-28%). Taken together, the data indicate that heterozygosity at the Vhl locus predisposes mice to a vascular phenotype ranging from angiectasis to hemangiosarcoma, consistent with the ability of this tumor suppressor gene to control the stability of HIF and regulate key proteins that participate in angiogenesis.

Tumorigenic potential of carbaryl in the heterozygous p53 knockout mouse model

The heterozygous p53 knockout mouse model was used to assess whether vascular tumors noted in a 2-year carcinogenicity study in CD-1 mice with carbaryl were induced through a genotoxic mechanism. This knockout mouse model was selected for carbaryl because of the high sensitivity of this model to genotoxic events and its low spontaneous incidence of tumors until 9-12 months of age. Carbaryl was administered continuously via the diet to groups of 20 male heterozygous p53 knockout mice at concentrations of 0, 10, 30, 100, 300, 1000 and 4000 ppm for 180 days. Histopathological examinations revealed no evidence of carbaryl-induced neoplasms of any type. In particular, no neoplastic or preneoplastic changes were noted in the vascular tissue of any of the organs examined. Only neoplasms, recognized as those that occur spontaneously in untreated mice of this strain, were sporadically observed in a few animals from the intermediate dose groups with no evidence of a dose- or treatment-related effect. Therefore, under the conditions of this study, the no-observed-effect level (NOEL) of carbaryl for neoplastic changes in male mice was 4000 ppm (around 716 mg/kg body weight/day). We conclude: (1) carbaryl does not appear to be a genotoxic carcinogen at least in male mice; (2) if the vascular tumors observed in the CD-1 mice are treatment-related, they could have been induced by a non-genotoxic mechanism; (3) the response in transgenic animals may provide useful complementary results to better assess carbaryl's potential genotoxic hazard to humans.

[A case of racemose hemangioma of a bronchial artery complicated with atrial septal defect and localized peripheral ground-glass opacity]

We report a case of racemose hemangioma of the right bronchial artery complicated with an atrial septal defect (ASD) and ground-glass opacity localized in the right upper lung lobe. A 42-year-old woman was admitted for the pre-operative assessment of ASD. Aortography and selective angiography revealed that the right bronchial artery was markedly dilated and convoluted, draining into the right intercostal arteries and the right upper pulmonary vein. The patient was suffering from exertional dyspnea, but produced no bloody sputum. Since videobronchoscopy showed normal mucosal findings without bronchiectasis, primary racemose hemangioma of the right bronchial artery was diagnosed, and was treated by ligation of the bronchial artery and patch-closure of the ASD. The ground-glass opacity observed preoperatively in the periphery of the right upper lung lobe vanished after surgery. This opacity was considered to have been localized pulmonary congestion due to augmented hydrostatic pressure in the right upper pulmonary vein, induced by increased pulmonary blood flow through the ASD and the drainage route of the racemose bronchial artery into right upper pulmonary vein.

Isolated cavernous sinus extramedullary relapse of chronic myelogenous leukemia following allogeneic stem cell transplant

Isolated extramedullary relapse of chronic myelogenous leukemia (CML) after allogeneic stem cell transplant is rare. A case is reported of a patient who developed a granulocytic sarcoma of the cavernous sinus 7 months after allogeneic transplant for CML. He presented with neurologic deficits, and a mass lesion was found on imaging. No evidence of hematologic relapse was identified by bone marrow histology or cytogenetics. A premortem diagnosis was not possible, and the patient died 2 months later of an intracerebral hemorrhage after receiving various therapies directed against a presumed infectious etiology. Granulocytic sarcoma should be considered in the differential diagnosis of mass lesions presenting after allogeneic transplant for CML, even if there is no evidence of medullary disease.

MR diagnosis of myxomatous aneurysms: report of two cases

We report two cases in which MR imaging was used to diagnose multiple cerebral aneurysms caused by cardiac myxoma. In one case, the diagnosis was confirmed with cerebral angiography. Myxomatous aneurysms characteristically appeared on T1-weighted images as contrast-enhancing focal fusiform dilatations of distal segments of the cerebral arteries. On T2-weighted images, these myxomatous aneurysms appeared as low signal intensity flow voids, sometimes associated with cerebral infarctions.

The spectrum of vascular lesions in the mammary skin, including angiosarcoma, after breast conservation treatment for breast cancer

BACKGROUND

With the general acceptance of lumpectomy, axillary staging, and radiotherapy as local treatment for infiltrating breast cancer, an appreciation is evolving for the spectrum of vascular lesions that occur in the mammary skin after this treatment. Most of these lesions develop within the prior radiation field after breast conservation treatment.

STUDY DESIGN

A retrospective chart and slide review was conducted, consisting of five patients with cutaneous vascular lesions after breast conservation treatment for infiltrating breast cancer.

RESULTS

The latent time interval from definitive treatment of breast cancer to the clinical recognition of vascular lesions ranged from 5 to 11 years. Two patients did not have either arm or breast edema, two patients had breast edema, and the fifth patient had arm edema. Lesions arising in the irradiated mammary skin included extensive lymphangiectasia (one), atypical vascular lesions (two), and cutaneous angiosarcoma (four).

CONCLUSIONS

Atypical vascular lesions at the skin margins of mastectomy may be predictive of recurrence after resection of angiosarcoma. Excision of skin from the entire radiation field may be necessary to secure local control of the chest wall in patients with cutaneous angiosarcoma after therapeutic breast radiotherapy.

Recurrent intravascular papillary endothelial hyperplasia developing from a pyogenic granuloma

Intravascular papillary endothelial hyperplasia (IPEH) is a rare benign vascular tumour. Many histological features are similar to those of low-grade angiosarcoma, a common, but more serious condition. Clinical and histological differentiation is important to avoid overtreatment of this benign condition. We report on a 34-year-old woman who developed recurrent IPEH at the site of a previously excised pyogenic granuloma.

Vascular tumors in livers with targeted inactivation of the von Hippel-Lindau tumor suppressor

von Hippel-Lindau (VHL) disease is a pleomorphic familial tumor syndrome that is characterized by the development of highly vascularized tumors. Homozygous disruption of the VHL gene in mice results in embryonic lethality. To investigate VHL function in the adult we have generated a conditional VHL null allele (2-lox allele) and null allele (1-lox allele) by Cre-mediated recombination in embryonic stem cells. We show here that mice heterozygous for the 1-lox allele develop cavernous hemangiomas of the liver, a rare manifestation of the human disease. Histologically these tumors were associated with hepatocellular steatosis and focal proliferations of small vessels. To study the cellular origin of these lesions we inactivated VHL tissue-specifically in hepatocytes. Deletion of VHL in the liver resulted in severe steatosis, many blood-filled vascular cavities, and foci of increased vascularization within the hepatic parenchyma. These histopathological changes were similar to those seen in livers from mice heterozygous for the 1-lox allele. Hypoxia-inducible mRNAs encoding vascular endothelial growth factor, glucose transporter 1, and erythropoietin were up-regulated. We thus provide evidence that targeted inactivation of mouse VHL can model clinical features of the human disease and underline the importance of the VHL gene product in the regulation of hypoxia-responsive genes in vivo.

Successful autologous peripheral blood stem cell transplantation for relapsed intravascular lymphomatosis

We describe a case of relapsed intravascular lymphomatosis (IVL) successfully treated with autologous PBSCT. A 59-year-old Japanese female patient with IVL who had achieved CR after six courses of biweekly CHOP therapy developed lymphoma. She achieved a second CR after six courses of modified biweekly CHOP therapy, followed by autologous PBSCH and high-dose chemotherapy (CBDCA, VP-16, MCNU, CY) with PBSCT. There has not been any evidence of recurrence 48 months after PBSCT. Our case suggests that PBSC is acceptable as a source for stem cell rescue in IVL.

Malignant vascular tumours of the pleura in "asbestos" workers and endothelial differentiation in malignant mesothelioma

BACKGROUND

Three cases of diffuse malignant vascular tumours of the pleura are described which mimicked malignant mesothelioma clinically and pathologically (so called "pseudomesothelioma"). All had occupational histories of exposure to asbestos. The relationship of these tumours to mesothelioma and asbestos exposure is discussed.

METHODS

To examine the histogenetic relationship between mesothelioma and these three tumours an immunohistochemical analysis of vascular marker (CD31, CD34, and Von Willebrand factor) expression was undertaken in 92 cases of pleural mesothelioma, in addition to these three tumours. Electron microscopic fibre analysis of lung tissue was performed on each of the three cases to assess asbestos fibre content.

RESULTS

Diffuse pleural epithelioid haemangioendotheliomas may closely resemble malignant mesothelioma clinically and pathologically but, of the 92 pleural mesotheliomas tested, none showed expression of CD31, CD34, and Von Willebrand factor. Although all three cases had claimed exposure to asbestos, ferruginous bodies typical of asbestos were only seen by light microscopy in case 2, and only in this subject was the asbestos fibre content raised in comparison with the range seen in a non-exposed background population. The latent period in the pleural epithelioid haemangioendotheliomas ranged from 18 to 60 years.

CONCLUSIONS

Endothelial differentiation does not appear to occur in mesothelioma and therefore should be clearly separated from it. No definite association between pleural epithelioid haemangioendothelioma and exposure to asbestos can be made from this small series but further investigation is warranted.

[Intravascular malignant lymphoma (angiotrophic large-cell lymphoma)]

Intravascular lymphoma (IVL) is characterized by proliferation of large malignant lymphoid cells within the lumen of small vessels. Sites usually affected include the central nervous system and skin although involvement of multiple organ symptoms have been described. IVL is very rare and aggressive type of lymphoma. Based on review of the literature we present clinicopathological, immunohistochemical and molecular features of the IVL. The etiological possibilities are discussed.

Human endothelial cells expressing polyoma middle T induce tumors

The middle T oncogene of murine polyomavirus (PymT) rapidly transforms and immortalizes murine embryonic endothelial cells (EC), leading to the formation of vascular tumors in newborn mice, by recruitment of host, non-transformed EC. These tumors are reminiscent of human vascular tumors like cavernous hemangioma, Kaposi's sarcoma or those characterizing Kasabach-Merrit syndrome. Here we investigate the in vitro and in vivo behavior of human primary umbilical cord vein EC expressing PymT. While PymT has been unable to transform human fibroblasts in earlier experiments or controls done here, mT expressing EC (PymT-EC) derived by infection with pLX-PymT retrovirus induce hemangiomas in nu/nu mice. These tumors contain not only human cells but also recruited mouse EC as shown by the presence of human and murine CD31 positive EC. In vitro analysis shows that PymT-EC retain endothelial specific markers like CD31, Von Willebrand factor, and VE-cadherin, and reach the confluence without signs of overgrowth. They are also responsive to vascular endothelial growth factor-A. However, their proliferation rate is increased. The balance between urokinase-type plasminogen activator and plasminogen activator inhibitor-1 is modified; RNA and catalytic activity for the former are elevated while PAI-1 RNA is reduced. In contrast with murine model, where the PymT EC cells become immortal, the effects induced by PymT in human EC are transient. After 12-15 passages, human PymT EC stop proliferating, assume a senescent phenotype, and lose the ability to induce hemangiomas. At the same time both the amount of middle T protein and the level of activation of pp60c-src lower.

Multinucleate cell angiohistiocytoma: report of two cases with no evidence of human herpesvirus-8 infection

Multinucleate cell angiohistiocytoma (MCA) is a vascular tumor of unknown pathogenesis. Possible misinterpretation of this disorder with Kaposi's sarcoma (KS), a human herpesvirus-8 (HHV-8)-associated tumor, prompted us to look for this virus in two women with MCA. None of the multiple skin specimens obtained from both our patients produced amplified HHV-8 DNA. Using a cell culture methodology similar to that used for KS, we established cell cultures from MCA lesions. While KS spindle cells are known to exhibit in vitro invasive properties and can be grown up to more than 20 passages, the MCA-derived cells were short-lived and were not able to traverse basement membranes. Taken together, our data support the hypothesis that MCA is not a neoplasm but a benign vascular proliferation which is clearly distinguishable from KS.

Benign lymphangioendothelioma of the thigh simulating a low-grade angiosarcoma

Benign lymphangioendothelioma (BL) is a rare vascular neoplasm that can histopathologically mimic a low-grade angiosarcoma or the patch stage of Kaposi sarcoma. We report on the case of a 49-year-old man with a benign lymphangioendothelioma on the right thigh that evolved on a vascular birthmark after a trauma. Because of constant pain and the slow but progressive growth of the lesion, we decided to excise the tumor. Three stages of surgery were needed to obtain negative margins. We review the reports of BL to date, with special attention to those that developed after trauma and those that had a preexistent vascular lesion, and expound on the histopathologic differential diagnosis with low-grade angiosarcoma.

The p53 heterozygous knockout mouse as a model for chemical carcinogenesis in vascular tissue

Heterozygous p53 knockout mice were investigated as a potential model for vascular tumor carcinogenesis. Groups of 20 male mice were exposed by gavage for 6 months to the vascular carcinogen urethane at 1, 10, or 100 mg/kg body weight/day. Wild-type and heterozygous p53 knockout control groups were exposed by gavage to the vehicle alone. Another group of 20 male mice received d-limonene by gavage (d-limonene is noncarcinogenic in mice). The high dose of urethane caused early mortality in the majority of mice associated with histopathologic evidence of toxicity and tumors, including a high incidence of benign and malignant vascular tumors, in all animals. At the intermediate dose, toxicity was less marked and 3 of 20 mice had tumors; mice that received the low dose did not have signs of toxicity or neoplasia. The two control groups had no tumors and the d-limonene group had one tumor of the prostate, which was considered spontaneous. We conclude that the p53 knockout mouse is a useful tool for investigating vascular tumorogenesis.

Hemobilia, intrahepatic hematoma and acute thrombosis with cavernomatous transformation of the portal vein after percutaneous thermoablation of a liver metastasis

A 53-year-old-man underwent US-guided percutaneous thermal ablation with a cooled-tip needle of three liver metastases from gastric cancer. Six days later, the patient was re-admitted for melena, scleral jaundice, and anemia. Abdominal US disclosed echogenic material in the gallbladder lumen (hemobilia) and a focal lesion with mixed echotexture in segment III (hepatic hematoma). On day 5 portal cavernomatosis was diagnosed at US and confirmed by color Doppler and a helical CT exam. The case described emphasizes that radio-frequency interstitial hyperthermia may cause not only traumatic injury of the liver parenchyma but also thermally mediated damage of vascular structures.

Stewart-Treves syndrome: lymphangiosarcoma following mastectomy

Lymphangiosarcoma (LAS) is an aggressive, malignant vascular tumor following long-lasting chronic lymphedema. Patients with LAS demonstrate a history of breast cancer treated by radical mastectomy in the majority of patients. In the 1960s the incidence of LAS in patients with a 5-year survival after radical mastectomy varied from 0.07 to 0.45%. Today, due to changes in the operative techniques of breast cancer, less chronic lymphedema is seen with only a scant number of LAS patients. The etiology of this enigmatic tumor is not yet completely understood. Histologically, LAS arises from vascular endotheliocytes, and all vascular sarcomas originating in the setting of a chronic lymphedema are categorized as LAS. There is no standard treatment of LAS. The treatment options include radical ablative surgery, radiation therapy, and chemotherapy. The prognosis of LAS is poor; long-term survival is the exception. Only early recognition and radical surgery offer a chance of cure.

The infant with a vascular tumor

Vascular birthmarks look alike in various tints of blue, pink, or red. These anomalies are either vascular tumors or vascular malformations. Hemangioma is the most common vascular tumor of infancy, typically appearing in the neonatal period. Hemangiomas grow rapidly during the first year of life and regress slowly during childhood. Treatment is indicated for problematic or endangering hemangiomas, usually the administration of corticosteroids or interferon-alfa, and in some instances, embolization or surgical resection. The more aggressive and rare vascular tumors, kaposiform hemangioendothelioma and tufted angioma, are often associated with thrombocytopenia and coagulopathy (Kasabach-Merritt phenomenon) and less responsive to pharmacological therapy. Vascular tumors, particularly hemangioma, are often confused with vascular malformations; although etiology, histology, and clinical behavior are quite different. Vascular lesions should be biopsied if there is any suspicion of malignancy.

Profile of extrahepatic portal venous obstruction in Mumbai

AIM OF THE STUDY

To study the clinical profile of extrahepatic portal venous obstruction (EHPVO) in a tertiary referral centre in Mumbai.

METHODOLOGY

Retrospective analysis of records of 113 patients with EHPVO, treated between January 1984 and May 1996.

RESULTS

Thirty eight of 54 (70.4%) patients in whom information was available were delivered at home. Eleven of the 50 (22%) had umbilical sepsis after birth. Median disease duration was 5 years (range 4 months-31 years), with age at initial presentation 13 (range 0.5-45) years; 24 (20%) patients presented after age 20 years. Eleven presenting initially with splenomegaly bled after 3 (1-14) years. Number of bleeding episodes per patient was 2.5 (1-12). 13 of 44 (29.6%) patients bled (first bleed or recurrence) after age 20 years. Twenty five (22.3%) had ascites at some time, 17/102 (16.7%) had hypersplenism, and hypoalbuminaemia was present in 20/103 (19.2%). Endoscopic sclerotherapy obliterated varices in 47/52 (90.4%) in 10.5 (3-40) sessions over 7 (1-100) months. Twenty three patients underwent surgery: devascularisation in 20 (with splenectomy in seven), distal lieno-renal shunt in two, and meso-caval shunt in one patient. Follow-up was available in 68 (60.2%) patients. Rebleeding after sclerotherapy occurred in 27/64 (42.2%), with median one (1-5) per patient; recurrence of varices was noted in 15/35 (42.9%) patients over 12 (3-39) months. Varices were present in 12 patients 163 (33-305) months after surgery.

CONCLUSIONS

Home delivery and umbilical sepsis may be risk factors in the development of EHPVO. A significant number of patients present or continue to bleed from varices after age 20. Variceal sclerotherapy is effective for eradication of oesophageal varices.

[Hydatid cyst in the hepatic hilum causing a cavernous transformation in the portal vein]

Portal cavernomatosis consists in the substitution of the portal vein by many fine, twisting venules leading to the liver. This phenomenon is produced as a consequence of anterior thrombosis of the portal vein and is associated with chronic pancreatitis, cancer of the pancreas, intraabdominal sepsis and cholelithiasis. The symptomatology may be nul or present as obstructive jaundice or portal hypertension. Diagnosis is made by Doppler echography. The treatment is portal shunt when symptomatology is produced. In patients with cholelithiasis requiring surgery, the shunt is advised prior to biliary surgery since perioperative hemorrhage, if present, may be incoercible as in the case herein described. We present a 84-year-old woman with portal cavernomatosis the etiology of which was a hydatidic cyst located in the hepatic bifurcation and treated with mebendazol 10 years previously. This etiology has not been previously reported.

Cancer incidence, morbidity and geothermal air pollution in Rotorua, New Zealand

BACKGROUND

The New Zealand city of Rotorua sits on a geothermal field. However, little is known about the possible health impacts of the geothermal emissions. This was an ecological study that examined cancer incidence and morbidity data for Rotorua.

METHODS

Cancer registry and hospital discharge (morbidity) data were obtained for the decade 1981-1990. Standardized incidence ratios (SIR) were calculated comparing Rotorua residents with those living in the rest of New Zealand. Diagnostic categories examined were based on known target organ systems of hydrogen sulphide toxicity.

RESULTS

Of the cancer sites, there was an elevated rate for nasal cancers. However, this was based on only four cases. The SIR for cancers of the trachea, bronchus and lung in Maori women was 1.48 (95% CI: 1.03-2.06). This was not explained by higher smoking rates. In the hospital discharge data, a number of diseases showed elevated SIR, notably diseases of the nervous system and the eye. To some extent, these effects were characteristic of effects induced by hydrogen sulphide and also mercury compounds. However, there were few data with which to assess whether significant mercury exposures had occurred, and other explanations were possible.

CONCLUSIONS

There are inadequate exposure data for Rotorua to permit conclusions on likely causal associations. However, some of the elevated disease rates were at least consistent with what one might expect to find if sufficient exposures to hydrogen sulphide and/or mercury were occurring.

Polyoma middle T-induced vascular tumor formation: the role of the plasminogen activator/plasmin system

The middle T antigen of murine Polyomavirus (PymT) rapidly transforms endothelial cells, leading to the formation of vascular tumors in newborn mice. Transformed endothelial (End.) cell lines established from such tumors exhibit altered proteolytic activity as a result of increased expression of urokinase-type plasminogen activator (uPA) and are capable of inducing vascular tumors efficiently when injected into adult mice. In this study we have used mice lacking components of the PA/plasmin system to analyze the role of this system in the transformation process and in tumor growth. We found that the proteolytic status of the host is not a critical determinant for PymT-induced vascular tumor formation. In addition, the lack of either uPA or tissue-type PA (tPA) activity is not limiting for the establishment and proliferation of End. cells in vitro, although the combined loss of both PA activities leads to a marked reduction in proliferation rates. Furthermore, the in vitro morphogenetic properties of mutant End. cells in fibrin gels could only be correlated with an altered proteolytic status in cells lacking both uPA and tPA. However, in contrast with tumors induced by PymT itself, the tumorigenic potential of mutant and wild-type End. cell lines was found to be highly dependent on the proteolytic status of both the tumor cells and the host. Thus, genetic alterations in the PA/plasmin system affect vascular tumor development, indicating that this system is a causal component in PymTmediated oncogenesis.

A patient with classical Kaposi's sarcoma and angiosarcoma: bad luck or a common aetiology?

Classical Kaposi's sarcoma and angiosarcoma are rare malignant tumours arising from vascular tissue. However, they have distinct histological features and appear also to differ in their epidemiology and pathogenesis. We present the case history of a patient in whom both these tumours occurred simultaneously. The relationship between these events is discussed in the light of the new virus, human herpes virus 8.

Spindle cell hemangioendothelioma. An analysis of 78 cases with reassessment of its pathogenesis and biologic behavior

Seventy-eight cases of spindle cell hemangioendothelioma (SCH) were studied to reevaluate its pathogenesis and determine its long-term behavior. Most of the original findings were confirmed by this study. The tumor occurred at all ages (8-78 years; median, 32 years; mean, 34 years). Males and females were equally affected. The tumor developed as a superficially located mass of the distal extremities (upper, 32 cases; lower, 30 cases). Four patients (5%) also had Maffucci's syndrome. The lesions were circumscribed red-brown masses occasionally containing phleboliths that consisted of cavernous blood spaces alternating with cellular areas consisting of collapsed vascular spaces separated by spindled fibroblastic cells. Often the endothelium lining the collapsed blood spaces appeared epithelioid with cytoplasmic vacuolization. The spindled fibroblastic cells lacked significant atypia and had at most a low level of mitotic activity. As a significant departure from what was originally reported, more than half of these cases (58%) were partially or completely intravascular. The vein containing the tumor often had an irregularly attenuated wall with small intimal herniations and intimal papillae traversing the lumen. Similar intimal changes in adjacent vessels suggest that SCH grows as a multifocal or contiguous process within vessels. Follow-up information was obtained in 40 cases, ranging from 1 month to 40 years (mean, 5.4 years). Despite conservative excisions in most patients (simple excision, 83%; wide local excision, 13%; amputation, 2%), prognosis was excellent. Fifty-eight percent experienced recurrences, but no patient developed metastasis and no patient died of the direct effects of the tumor, although one patient with Maffucci's syndrome developed a concurrent angiosarcoma. We conclude that SCH is a primary benign vascular neoplasm or malformation similar to angiomatosis in which alterations in blood flow might explain some of the secondary features. Areas of diminished blood flow result in vascular collapse with formation of the "cellular" zones, and areas of vascular engorgement with stasis promote thrombosis and organization. Local "recurrences" probably represent contiguous spread along or multifocal involvement of a vessel. Because there is no evidence that this lesion has metastatic potential, we suggest that the lesion be designated spindle cell hemangioma for solitary lesions and spindle cell hemangiomatosis for multifocal lesions.

[Restenosis: physiopathology, treatments and prevention]

Despite fifteen years of extensive research, we still do not know how to predict or prevent restenosis. Angioplasty induces lesions in the intima, media and sometimes adventitia, resulting in a cicatricial process comprising proliferation and migration of smooth muscle cells towards the intima and secretion of extracellular matrix, leading to the formation of a neointima. Since angioplasty is associated with the simultaneous development of neointimal hyperplasia and restenosis, a cause and a effect relationship has therefore been proposed between neointimal hyperplasia and restenosis. All the restenosis prevention strategies based on inhibition of smooth muscle cell proliferation, which successfully limited restenosis in animal models have failed in man, due to the hazardous extrapolations from experimental models which are very different from the atheromatous lesions observed in man, rather than to the use of animal models in general. It is reasonable to wonder whether we have not selected the wrong target: is smooth muscle cell proliferation really responsible for restenosis? Experimental results supported by histological and ultrasonographic data in man, show that the cicatricial process which induces restenosis consists of constrictive remodelling, which decreases the perimeter of the external elastic lamina and the lumen. The use of stents appears to be the primary strategy designed to limit restenosis and prevent constrictive remodelling in man, even if it stimulates neointimal hyperplasia. Progress in the understanding of the mechanisms of postangioplasty remodelling open new perspectives in the prevention of restenosis.