Congenital cutaneous multifocal kaposiform hemangioendothelioma

Multifocal Kaposiform Hemangioendothelioma in a Newborn With Confirmatory Histopathology

Kaposiform hemangioendothelioma is classified as a locally aggressive vascular tumor of childhood resulting from abnormal angiogenesis and lymphangiogenesis. Most commonly, KHE presents as a single tissue mass, ranging from an erythematous papule to a violaceous indurated tumor. Definitive diagnosis requires tissue sampling with the demonstration of ill-defined nodules and fascicles of spindle-shaped D2-40 positive endothelial cells, forming slit-like vascular channels. This newborn presented with multifocal cutaneous Kaposiform hemangioendothelioma associated with Kasabach-Merritt phenomenon confirmed on histopathology with immunostaining.

Cellular Variant of Kaposiform Lymphangiomatosis: A Report of Three Cases, Expanding the Morphologic and Molecular Genetic Spectrum of this Rare Entity

Kaposiform lymphangiomatosis (KLA) is a very rare form of generalized lymphatic anomaly, consisting of a diffuse proliferation of abnormal, dilated lymphatics and small fascicles of hemosiderin-laden spindled lymphatic endothelial cells. KLA occurs in children and young adults and may present with multicentric disease, pleural and pericardial effusions, and life-threatening coagulopathy. Genetically, KLA most often harbor somatic activating mutations in NRAS. We recently encountered 3 cases of KLA with cellular features, resembling kaposiform hemangioendothelioma (KHE) and studied their clinicopathologic, radiologic and molecular genetic features. The patients (1 male, 2 females; ages 2 years, 2 months, 4 years) presented with multicentric disease involving skin, soft tissue, bone and spleen, and thrombocytopenia/coagulopathy. Advanced imaging studies confirmed multicentric disease. Biopsies (skin, soft tissue, bone, spleen) demonstrated both conventional KLA and much more cellular foci, consisting of sheets, nodules, glomeruloid structures, and "sieve-like" arrays of lymphatic endothelial cells (positive for CD31 and D2-40). Cellular areas superficially resembled KHE but displayed more epithelioid cytology and lacked surrounding hyaline fibrosis and minute platelet aggregates. Molecular genetic studies demonstrated NRAS c.181C>A p.Q61K (Gln61Lys) in 2 specimens from one patient and HRAS p.A59_Q61delinsGGSIL in another. Two patients were treated with sirolimus; all are currently alive with stable disease. We conclude that cellular morphology in KLA, a previously undescribed feature, does not appear to be associated with clinical features, site of disease, mutation type, response to sirolimus, or outcome. Although cellular KLA may mimic KHE, there are sufficient clinical, morphologic, and genetic differences such that these are likely unrelated diseases.

What to Look Out for in a Newborn with Multiple Papulonodular Skin Lesions at Birth

Multiple papulonodular skin lesions at birth can indicate the presence of various benign and malignant disorders. Although the lesions’ clinical aspect (color and consistency, in particular) may steer the clinician towards one disorder or another (infantile myofibromatosis, xanthogranuloma, or metastatic neuroblastoma), the diagnosis can only be confirmed by the histopathologic assessment of a biopsy. In neonates, a rapid but accurate diagnosis is critical because skin lesions may be the first manifestation of a malignant disorder like leukemia cutis or metastatic neuroblastoma. Here, we review the various disorders that may manifest themselves as multiple skin lesions at birth.

Congenital Cutaneous Kaposiform Hemangioendothelioma in a Newborn Calf

A one-day-old female Holstein calf was presented with subcutaneous masses spread over the whole body. Macroscopically, the masses were firm in touch, greyish-white in colour, 0.5-2 cm in diameter range. Histopathological examination confirmed the cutaneous Kaposiform hemangioendothelioma (KHE). Microscopic examination of the tumor revealed sheets of spindled endothelial cells forming vascular slits. Immunohistochemically, the tumor cells and capillaries gave strongly positive reaction for CD31 while vimentin, alpha smooth muscle actin and cytokeratin AE1/AE3 were negative. In this case, macroscopical, detailed histhopathological and immunohistochemical findings of congenital KHE reported firstly in a newborn calf.

Clinical observations in mesh suture treatment for infants of Kasabach-Merritt phenomenon

AIM

This study aims to evaluate the efficacy and adverse effects of the mesh suture treatment for infants of Kasabach-Merritt phenomenon and to report our treatment experience.

METHODS

Of the three patients, two of the cases occurred in the scalp and one occurred in the back of the chest, with platelet counts < 40 × 10⁹ /L before the treatment, reduced fibrinogen levels and increased D-dimer levels. All the three patients underwent the mesh suture treatment of the tumour area. Post-treatment observations were made regarding the surface colour and texture of the tumours, periodic routine blood examination results, fibrinogen and D-dimer levels.

RESULTS

After treatment, the degree of swelling on the tumour surface was reduced, surface tension was decreased, the tumour colour turned pale red from dark red and the skin gradually returned to normal. Two days after treatment, the platelet counts increased to 70 × 10⁹ /L or higher; the platelet count reached a normal level after 1 week in two cases. The fibrinogen level increased in varying degrees after treatment, whereas the D-dimer level was reduced. One case showed a small amount of exudate at the suture area, 1 month after the treatment; improvements were observed 3 days after changing the local dressing. All the patients were followed up for 6 months to 1 year, during which the patients showed complete regression of the lesion and relapse, normal platelet counts and normal fibrinogen and D-dimer levels.

CONCLUSIONS

We recommend the mesh suture treatment as the first treatment of choice for paediatric Kasabach-Merritt phenomenon.

Multifocal kaposiform hemangioendothelioma of soft tissue with bilateral pulmonary involvement in an adolescent

Kaposiform hemangioendothelioma (KHE) is a rare, locally aggressive vascular tumor of intermediate malignancy with resemblance to Kaposi sarcoma. It occurs predominantly in pediatric age groups as a cutaneous lesion with focal infiltration into the adjacent soft tissue and bone. Although visceral involvement is very uncommon, several cases with bone, retroperitoneal, or mediastinal involvement have been described. KHE has been reported to occasionally occur in unusual sites such as the thymus, tonsils, larynx, paranasal sinuses, deltoid muscle, spleen, uterine cervix, thoracic spine, and even the breast. Multifocal KHE is an extremely rare entity with few reports available in the literature, none of which describes pulmonary involvement. Herein, we report a unique case of multifocal KHE in a 13-year-old boy presenting with a huge soft tissue mass in the upper extremity complicated by bilateral pulmonary nodules that developed into large, necrotic tumor masses.

Hemangioendothelioma

Hemangioendothelioma is the term used to name those vascular neoplasms that show a borderline biological behavior, intermediate between entirely benign hemangiomas and highly malignant angiosarcomas. Although originally spindle cell hemangioendothelioma was proposed as a specific clinicopathologic variant of hemangioendothelioma, currently, it is considered as an entirely benign lesion, and thus, the name spindle cell hemangioma seems to be the most accurate for this lesion. Authentic hemangioendotheliomas involving the skin and soft tissues include papillary intralymphatic angioendothelioma (also known as Dabska tumor), retiform hemangioendothelioma, kaposiform hemangioendothelioma, epithelioid hemangioendothelioma, pseudomyogenic hemangioendothelioma (also known as epithelioid sarcoma-like hemangioendothelioma), and composite hemangioendothelioma. Each of these neoplasms exhibit characteristic histopathologic features. The most characteristic finding of papillary intralymphatic hemangioendothelioma consists of papillary tufts, with a central hyaline core lined by hobnail-like endothelial cells protruding into the lumina. Retiform hemangioendothelioma is an infiltrative neoplasm composed of elongated arborizing vessels, arranged in an anastomosing pattern that resembles that of the rete testis, and lined by a single layer of hobnail-like endothelial cells that protrude within the narrow lumina. Kaposiform hemangioendothelioma is composed of several solid poorly circumscribed nodules, and each nodule is composed of a mixture of small capillaries and solid lobules of endothelial cells arranged in a glomeruloid pattern. A frequent finding consists of the presence of areas of lymphangiomatosis adjacent to the solid nodules. Epithelioid hemangioendothelioma is composed of cords, strands, and solid aggregates of round, oval, and polygonal cells, with abundant pale eosinophilic cytoplasm, vesicular nuclei, and inconspicuous nucleoli, embedded in a fibromyxoid or sclerotic stroma. Many neoplastic cells exhibit prominent cytoplasmic vacuolization as an expression of primitive vascular differentiation. Pseudomyogenic hemangioendothelioma is a poorly circumscribed, fascicular lesion with infiltrative borders composed of round or oval neoplastic cells, with vesicular nuclei and inconspicuous nucleoli, and ample homogeneous eosinophilic cytoplasm, giving them a rhabdomyoblastic appearance. Finally, composite hemangioendothelioma is the term used to name locally aggressive vascular neoplasms of low-grade malignancy showing varying combinations of benign, low-grade malignant, and high-grade malignant vascular components. From the immunohistochemical point of view, proliferating cells of all hemangioendotheliomas express a lymphatic endothelial cell immunophenotype. Most hemangioendotheliomas are low-grade vascular neoplasms, with a tendency to recur locally and a low metastatic potential, mostly to regional lymph nodes. Epithelioid hemangioendothelioma, especially large lesions and those located in deep soft tissues, seems to have a more aggressive biological behavior.

Kaposiform hemangioendothelioma in multiple spinal levels without skin changes

Kaposiform hemangioendothelioma is a rare vascular tumor of childhood that is locally aggressive but has little metastatic potential and by itself is not known to be lethal. It most commonly presents as a superficial or deep soft tissue mass with associated cutaneous lesions. Kasabach-Merritt phenomenon, a condition characterized by profound thrombocytopenia and life-threatening hemorrhage, often is associated with kaposiform hemangioendothelioma. Six cases of kaposiform hemangioendothelioma have been reported in bone, two of which were located in extracraniofacial bones. We report a diagnostically challenging case of a 6-year-old girl with kaposiform hemangioendothelioma of the thoracolumbar spine without Kasabach-Merritt phenomenon or cutaneous lesions.

Kaposiform hemangioendothelioma

Kaposiform hemangioendothelioma (KHE) is a rare, locally aggressive vascular neoplasm that mainly occurs during childhood. It generally originates on the skin, usually affecting deeper tissue by infiltrative growth. It appears as one or multiple masses, and in most cases is associated to consumptive coagulopathy (Kasabach-Merritt syndrome), and lymphangiomatosis. Although visceral involvement is very uncommon, several cases with bone, retroperitoneal, or mediastinal involvement have been described. These tumors tend to be locally invasive, but are not known to produce distant metastases. The development of KHE in adolescents or in adults is very rare, but cases have also been described. Several factors are associated with the outcome of patients with KHE: accessibility to surgical excision, location (cutaneous versus visceral), size of tumoral mass, clinical response to interferon and glucocorticoids, and the absence of lymphangiomatosis and Kasabach-Merritt syndrome, may result in partial remissions. On the other hand, bulk visceral masses lead to a 40-50% mortality rate, mainly due to progressive failure of the infiltrated organ(s), in spite of interferon, glucocorticoids, and combined chemotherapy. In conclusion, the onset of a consumptive coagulopathy following the presence of a vascular tumor, in children as well as in older patients, should spark suspicion of KHE, among other entities.

Kaposiform hemangioendothelioma: a rare cause of spontaneous hemothorax in infancy. Review of the literature

Kaposiform hemangioendothelioma is a rare vascular tumor found almost exclusively in early childhood often associated with a life-threatening thrombocytopenia and consumptive coagulopathy known as Kasabach-Merritt phenomenon. The natural history of these lesions and treatment remains controversial. We portray a case of a spontaneous hemothorax in a 2-month-old female infant and review of 153 reported cases in attempts to better delineate the available treatment options.

Vascular neoplasm in a newborn male

Kaposiform hemangioendothelioma was initially described in 1979 and is a rare pediatric vascular tumor that may be associated with Kasabach-Merrit phenomenon. We present a newborn boy who had a large vascular lesion over his left iliac crest without evidence of retroperitoneal involvement or inguinal lymphadenopathy. We briefly review the neoplasm's unique characteristics, histopathology, prognosis, and treatments.

Multifocal kaposiform haemangioendothelioma

Kaposiform haemangioendothelioma (KHE) is a rare, locally aggressive vascular spindle cell proliferation, with resemblance to Kaposi's sarcoma. This tumour usually occurs in skin and retroperitoneum of infants and young children and is often complicated by the Kasabach-Merritt phenomenon (KMP). A 3-year-old boy presented with a right submandibular swelling due to lymphadenopathies, a violaceous skin lesion at the left commissure of the lips and an ill-defined lesion in the right thyroid lobe. There were some signs of KMP. Histological examination revealed a typical infiltrative multilobular spindle cell proliferation with slit-like vascular spaces in these three localisations. Immunohistochemical stains showed positivity for CD34 and CD31 and many alpha-smooth muscle actin-positive spindle cells around the vascular spaces. There was no Herpes virus type 8 expression. The presented case is unique in two ways. First, thyroid involvement of KHE has never been described in the literature until now. Secondly, and most remarkably, the multifocal presentation in three anatomically distinct and separated localisations is extremely unusual.

Hemangioendotelioma kaposiforme torácico. Cuatro casos con evolución variable

INTRODUCTION

Kaposiform hemangioendothelioma (KHE) is a rare, frequently congenital, neoplasm associated with the Kasabach-Merritt phenomenon (KMP) and predilection for the trunk. Its clinical course is unpredictable. A child with KHE can die as a result of hemorrhage or show early spontaneous regression. In addition various and concurrent therapies can be used to treat this tumor and it is difficult to predict which treatment will be successful.

MATERIAL, METHODS AND RESULTS

We present four consecutive cases of KHE (larger than 20 cm) of the thorax. All patients developed KMP, without skin involvement in one patient. Patient 1, a neonate with KHE occupying both hemithoraces (nearly 50% of the body surface area), died shortly after birth due to coagulopathy and generalized bleeding. Patient 2, a neonate, was treated with interferon alpha-2a and showed accelerated correction of coagulopathy and complete tumoral regression at 9 months. Patient 3 showed no response to steroids, interferon or vincristine therapy. Thrombocytopenia (platelet count 40,000) persisted for 8 years and was resolved by administration of aspirin plus ticlopidine, without tumoral disappearance. Patient 4 underwent incomplete removal of the tumor on her right chest wall after showing no response to antiangiogenic therapy. The coagulopathy persisted and a second radical surgical procedure resolved KMP.

CONCLUSION

Given the variable response to pharmacological treatment and the scant possibilities of surgical resection, the management of KHE with KMP must include a multidisciplinary approach. As little is known about the pathogenesis of these highly aggressive vascular tumors, further molecular research is needed to understand their long-term behavior.

Life-threatening cutaneous conditions in neonates

One of the major medical concerns in neonates is their vulnerability to life-threatening complications. Early diagnosis of potentially serious medical conditions is essential in prevention of such complication by prompt administration of appropriate treatments. Recognition of cutaneous manifestations of potentially fatal diseases may assist a clinician in management of newborns. To overview the full spectrum of this category of conditions, Medline search was performed for cases of cutaneous manifestations associated with mortality during the first month of live that were published in the English language literature since 1977. This is a concise review of the clinical aspects of most of the potentially life-threatening disorders in neonates divided by basic morphology of their cutaneous manifestations.

Vascular tumors of the skin: A selective review

Cutaneous vascular proliferations are a vast and complex spectrum. Many appear as hamartomas in infancy; others are acquired neoplasms. Some vascular proliferations are hyperplastic in nature, although they mimic hemangiomas, i.e., neoplasms. The vast majority of the vascular lesions are hemangiomas. Between the hemangiomas and frankly angiosarcomas, there is a group of neoplasms that are angiosarcomas, albeit ones of low grade histologically and, probably, biologically. The term "hemangioendothelioma" has been created to encompass these neoplasms. Vascular proliferations are, fundamentally, composed of endothelial cells. Some hemangiomas, however, contain also abundant pericytic, smooth muscle, or interstitial components, or a combination of them. These heterogeneous cellular components are present usually in hemangiomas. Some of the newly described vascular proliferations, however, are difficult to differentiate from some of the angiosarcomas. Others are markers, occasionally, of serious conditions such as Fabry's Disease (angiokeratoma) and POEM's syndrome (glomeruloid hemangioma). Kaposi's sarcoma continues to be an enigma. The demonstration of Herpes virus 8 in this condition raises doubt about its neoplastic nature. The demonstration of endothelial differentiation of its nodular lesions is tenuous and its true nature remains unresolved. While physicians have known about post-mastectomy angiosarcomas from the origin of the radical mastectomy, a new group of unusual vascular proliferations of the mammary skin are being defined. These lesions arise in the setting of breast-conserving surgical treatment with adjuvant radiation therapy. The incubation period is usually 3 to 5 years, in contrast with the 10, or more, in classical cases of post-mastectomy angiosarcoma. These lesions usually are subtle, both clinically and histologically, in contrast with the "classical," dramatic presentation of mammary angiosarcoma. The spectrum of findings ranges from "simple" lymphangiectasia-like vascular proliferations to unequivocal angiosarcomas. The pathogenesis of these lesions remains a mystery. There are very few clues that allow one to separate hemangiomas from angiosarcomas. The presence of heterologous cellular elements and, particularly, well-developed smooth muscle components tends to favor a hemangioma. Similarly, the presence of thrombosis usually supports hemangioma. Nevertheless, there are no unequivocal or reliable individual diagnostic criteria. A thorough knowledge of the different conditions and their differential diagnoses eventually leads to the proper diagnosis in most cases.

Kaposiform Hemangioendothelioma

Kaposiform hemangioendothelioma (KH) is a rare tumor of childhood often associated with Kasabach-Merritt phenomenon (KMP) and occasionally lymphangiomatosis. Although generally considered distinct from other vascular neoplasms, its rarity has precluded a thorough study of its immunophenotypic profile and long-term behavior. Thirty-three cases of KH were reviewed and immunostained for alpha-smooth muscle actin, various endothelial markers (CD31, CD34, vWf, FLI1), a platelet marker (CD61), and the juvenile hemangioma-associated markers GLUT-1 and Lewis Y antigen (LeY). In addition, the presence of HHV-8 was evaluated by RT-PCR. The patients (20 males and 13 females) ranged in age from 2 weeks to 20 years (mean 3 years 9 months). Tumors developed on the extremities (17 cases), head/neck (8 cases), and other sites (8 cases) and affected both superficial and deep soft tissue. Those in the skin presented as slightly raised blue-red lesions. More than half of the patients presented with KMP (14 of 25). Tumors consisted of irregular, infiltrating nodules of compressed vessels, which modulated between areas resembling a capillary hemangioma and Kaposi sarcoma (KS). Endothelial cells in nodules were CD31, CD34, and FLI1 positive but negative for GLUT1 and LeY. Scattered "epithelioid" or glomeruloid islands featuring endothelium associated with clusters of plump alpha-smooth muscle actin-positive pericytes, stippled hemosiderin, and CD61-positive fibrin thrombi likely represent the morphologic sites of platelet consumption. Small and large lymphatic channels occurred in 22 of 33 cases and were typically seen peripheral or deep to the main tumor mass. HHV-8 transcripts were not identified (0 of 3 cases). Follow-up information was available in 22 patients (range 8 months to 15 years; mean 2 years) and indicated that 3 died of disease, 8 were alive with disease, and 10 were alive without residual disease. Two patients developed regional perinodal soft tissue involvement, but none developed distant metastases. KH is a lesion having both a vascular and lymphatic component. Its common association with KMP probably relates in part to unique architectural features that favor turbulent blood flow and platelet activation. KH can also be reliably separated from JH by GLUT-1 and LeY immunostaining, indicating differences in the morphologic and functional attributes of the endothelium between the two lesions. The absence of HHV-8 in KH underscores a different pathogenesis from Kaposi sarcoma. Our study, the largest to date, emphasizes that mortality is due to KMP and not metastatic disease, which appears limited to regional perinodal soft tissue. Given this behavior, its continued classification as a vascular tumor of intermediate malignancy is warranted.

Retroperitoneal kaposiform hemangioendothelioma with tufted angioma-like features in an infant with Kasabach-Merritt syndrome

Kasabach-Merritt syndrome denotes profound thrombocytopenia and coagulopathy in an infant with a vascular tumor. A retroperitoneal vascular tumor with an unusual combination of histopathological features is reported, and compared with vascular lesions described in the reported cases of Kasabach-Merritt syndrome in the literature. A large retroperitoneal tumor that had expanded through the sigmoid mesocolon into the sigmoid colon wall was resected from an 8-month-old infant with fully developed Kasabach-Merritt syndrome. Histological examination revealed a combination of venous (cavernous) malformation, kaposiform hemangioendothelioma and tufted angioma-like areas. Cellular tumor components (especially tufted angioma-like parts) infiltrated the wall of the sigmoid colon to the submucosal level. Immunohistochemical staining with antibodies to the Ki-67 antigen and proliferating cell nuclear antigen showed a low proliferative activity, whereas the antiapoptotic bcl-2 protein was expressed diffusely in tumor cells. This is the first reported case of a vascular tumor with tufted angioma-like elements found in the retroperitoneum, and the first reported in combination with kaposiform hemangioendothelioma and venous malformation in the same lesion. Considering the immunohistochemical results and overlapping histological features, it may be considered that tufted angioma and kaposiform hemangioendothelioma represent different growth patterns or stages in the development of a single type of hemangioma.

Kaposiform hemangioendothelioma: five patients with cutaneous lesion and long follow-up

Kaposiform hemangioendothelioma is a rare locally aggressive vascular tumor of the skin, deep soft tissue, and bone in children, characterized by infiltrating nodules and sheets of spindle cells, and unmistakable resemblance to Kaposi's sarcoma. More than 60 patients with such tumor have been reported so far, and while many have died as a result of extensive disease and severe coagulopathy, the long-term biologic behavior of this tumor remains undetermined. We describe five patients with kaposiform hemangioendothelioma and a mean follow-up of 19 years, ranging from 8 to 35 years. This report emphasizes on the importance of cutaneous lesions being the most commonly affected site, but also for its clinical diversity. Early diagnosis is possible even for a small skin lesion, which may be critical for the treatment of a potentially fatal deep-seated extensive tumor. All five patients are well, and three of them with persistent vascular tumor, which has carried two patients from childhood to adult. Although the behavior of this tumor might have been modified by radiation or interferon in three patients, this series indicates that kaposiform hemangioendothelioma is incapable of metastasis, despite a protracted course of many decades with no tendency for spontaneous regression.