Hemangioendothelioma with intravascular coagulation and ischemic colitis

Detection of fibrin generation alterations in dogs with haemangiosarcoma using resonance thrombography

OBJECTIVE

The objective of the study was to examine the alterations of fibrin generation in dogs with haemangiosarcoma using resonance thrombography. The second objective was to evaluate the sensitivity of this method for the detection of hypofibrinogenaemia and/or increased fibrin(ogen) degradation product (FDP) concentration.

ANIMALS, METHODS

Resonance thrombogram (RTG) measurements with two different instruments were performed in 30 unselected dogs with haemangiosarcoma, 14 of which had decreased fibrinogen and 28 of which had an increased FDP concentration (p<0.0001).

RESULTS

The RTG-reaction time was less sensitive than the fibrin formation time (RTG-f) and fibrin amplitude (RTG-F). The RTG-f and RTG-F indicated reliably a decrease in fibrinogen concentration (sensitivity: 0.93). The sensitivity of detection of increased FDP levels was considerably higher than that of thrombin time. However, false-negative results were found even at FDP concentrations > or =120 mg/l, especially in cases with high fibrinogen level. Both machines showed similar sensitivity.

CONCLUSIONS

The results of this study indicate that canine haemangiosarcoma is frequently associated with severe alterations of fibrin generation due to low fibrinogen and high FDP levels leading to distinct RTG abnormalities. The global test RTG reacts sensitively to a decreased fibrinogen level whereas its accuracy to detect FDP concentrations occurring under pathophysiological conditions is limited. A significant alteration of fibrin generation induced by FDPs may not occur until the serum FDP concentration exceeds 60 mg/l.

Kaposiform hemangioendothelioma: a locally aggressive vascular tumor

Kaposiform hemangioendothelioma is a locally aggressive, endothelial-derived spindle cell neoplasm that occurs exclusively in infants and adolescents. Lesions are characterized by rapid growth and extension, and are often associated with Kasabach-Merritt syndrome and lymphangiomatosis. Clinically nonspecific, they can appear as tender rapidly expanding red plaques, nodules, grouped papules, or telangiectasias. The histology is distinctive, however, as it combines features of tufted angioma, progressive lymphangioma, and Kaposi's sarcoma in a characteristic pattern. We describe a patient with kaposiform hemangioendothelioma currently controlled with systemic prednisone.

Thrombocytopenic coagulopathy (Kasabach-Merritt phenomenon) is associated with Kaposiform hemangioendothelioma and not with common infantile hemangioma

Children with a large vascular tumor and associated Kasabach-Merritt coagulopathy respond inconsistently to therapy and have a high mortality rate. For this reason, we undertook a retrospective study of 21 such patients, and focused on clinical, radiographic, and histopathologic features. The male to female ratio was 1:1.6. Tumor was noted at birth in 50 percent of patients; the remainder appeared throughout infancy. The location was cervicofacial (n = 2), shoulder/upper limb (n = 4), trunk including retroperitoneum (n = 11), and lower limb (n = 4). These tumors grew rapidly to large size and were characterized by cutaneous purpura, edema, and an advancing ecchymotic margin. In contrast to common hemangioma, magnetic resonance imaging showed diffuse enhancement with ill-defined margins, cutaneous thickening, stranding of subcutaneous fat, hemosiderin deposits, and small feeding and draining vessels. All tumors were Kaposiform hemangioendothelioma (KHE); none were infantile hemangioma. Light microscopy showed irregular lobules or sheets of poorly formed, small vascular channels infiltrating and entrapping normal tissues. Characteristic features included spindle-shaped endothelial cells, diminished pericytes and mast cells, microthrombi, and hemosiderin deposits. Wide endothelial intercellular gaps and incomplete basement membranes were seen by electron microscopy. Dilated, hyperplastic, lymphaticoid channels were prominent in one tumor. KHE in 14 infants was treated with interferon alpha-2a: 6 had accelerated regression; 2 had stabilization of growth; and 6 evidenced no response. The mortality rate was 24 percent (5 of 21); this included three infants with retroperitoneal KHE. Kasabach-Merritt phenomenon does not occur with common hemangioma. Rather it is associated with the more aggressive KHE and rarely with other vascular neoplasms. Variable response to current pharmacologic therapy underscores our inadequate knowledge of the pathogenesis of thrombocytopenia in KHE.

A case of adrenal cavernous hemangioma

Adrenal hemangiomas are rare tumor. Only 29 surgical cases have been reported. Although rare, adrenal hemangiomas should be included in the differential diagnosis of adrenal neoplasms. We report an additional case of adrenal hemangioma that was removed surgically, and the pertinent literature is reviewed.

Recently characterized vascular tumours of skin and soft tissues

This review summarizes the clinicopathological features of a number of vascular tumours that have been characterized only in recent years. These include: glomeruloid haemangioma, a multifocal vascular lesion associated with POEMS syndrome: Kaposi-like infantile haemangioendothelioma, a borderline malignant tumour occurring in the retroperitoneum of infants, mimicking Kaposi's sarcoma histologically; giant cell angioblastoma, characterized by proliferated vessels with a granuloma-like appearance; benign lymphangioendothelioma (progressive lymphangioma), slowly-growing macule or plaque over the trunk or limb, mimicking low-grade angiosarcoma histologically; targetoid haemosiderotic haemangioma, a benign lesion with a distinctive annular appearance and histologically overlapping with benign lymphangioendothelioma; spindle cell haemangioendothelioma, a lesion located mostly in the distal extremities, characterized by cavernous vascular spaces, spindle cells with interspersed narrow vascular channels and scattered plump vacuolated endothelial cells; acquired tufted angioma, characterized by 'cannon-ball' involvement of the dermis by lobules of pericyte-rich capillaries; sinusoidal haemangioma, a distinctive variant of cavernous haemangioma which may be confused with angiosarcoma; and epithelioid angiosarcoma, a highly aggressive tumour of deep soft tissue mimicking metastatic carcinoma and co-expressing endothelial and epithelial markers.

Infantile hemangioendothelioma of the pelvis associated with Kasabach-Merritt syndrome

A case of infantile hemangioendothelioma of the pelvis in a newborn male infant is described. Shortly after delivery, a large abdominal mass was found by external examination. CT scan revealed a hypervascular retroperitoneal pelvic mass invading the lumbar spinal column. Exploratory laparotomy was performed and biopsy revealed infantile hemangioendothelioma. The tumor was associated with profound thrombocytopenia, intratumoral hemorrhage, and right hydroureteronephrosis. After treatment with high dose steroids, Cytoxan, and external beam radiation for 2 months, the patient was discharged with persistent thrombocytopenia requiring platelet transfusions. The hydroureteronephrosis has also not improved. The literature on this subject is reviewed.

Hemangioma with Kaposi's sarcoma-like features: report of two cases

We describe two children with vascular neoplasms that resembled Kaposi's sarcoma in places. Both presented with intraabdominal masses and severe thrombocytopenia. At autopsy the tumors extensively infiltrated the peritoneum and retroperitoneum and surrounded or invaded numerous organs including the kidneys, pancreas, adrenal glands, gastrointestinal tract, mesentery, and lymph nodes in both cases, and spleen or bone marrow in one case each. The neoplasms were histologically identical and displayed two patterns: dilated vascular spaces (angiomatous areas) lined by flat endothelial-like cells and areas of spindle cells forming slitlike vascular spaces similar to those described in Kaposi's sarcoma. Tumor cells in both cases expressed markers for endothelial cells. The clinical and histologic character of these neoplasms differentiates them from Kaposi's sarcoma, hemangioendothelioma, and from conventional juvenile hemangioma.