Congenital capillary proliferation of the kidney: a distinctive renal vascular lesion of childhood.

Renal vascular lesions (RVL) are rare, and their morphological spectrum remains largely unknown, particularly in children. In this study, we characterize the clinicopathological features of RVL in a cohort of 12 children. Seven lesions were classified as previously recognized entities: vascular malformations (4), papillary endothelial hyperplasia (2), and pyogenic granuloma (lobular capillary hemangioma; 1). An eighth lesion showed nonspecific findings, which were interpreted as reactive during our review. The remaining 4 cases presented either prenatally, at birth, or shortly after birth and were morphologically similar. These were characterized by a peculiar pattern of capillary proliferation with entrapment of native renal structures, variable amounts of extramedullary hematopoiesis and reactive lymphocytes, foci of infarction and hemorrhage, and the presence of feeding and draining vessels at their periphery. To our knowledge, this represents a previously undescribed congenital vascular lesion involving the kidney, which we have descriptively and provisionally termed congenital capillary proliferation of the kidney (CCPK). While it is unclear whether CCPK represents a malformation or neoplastic proliferation, it shows overlapping features with congenital hemangioma of the liver (solitary congenital hepatic hemangioma) and congenital nonprogressive hemangioma (CNH) of the skin and soft tissue, suggesting a possible common pathogenesis among these 3 entities.

Lymphocyte-rich capillary-cavernous hemangioma of the mitral valve: a case report and review of the literature.

Valvular hemangioma incidence is extremely low. In this report, we describe a 62-year-old man who presented with mild edema of the lower limbs. An echocardiogram revealed an incidental 1.3-cm diameter mass on the anterior mitral valve leaflet for which he underwent surgical resection and mitral valve replacement. Histopathological examination showed a lymphocyte-rich capillary-cavernous hemangioma. The exuberant lymphoid stroma is unusual for hemangioma and represents an undescribed pattern of cardiac hemangioma. Including the present report, only 13 cases of mitral valve hemangioma have been reported to date. Most patients are adult. Mitral hemangioma originates in the atrial aspect of the valve and involves more commonly the anterior leaflet. The average maximum diameter of the lesion is 1.7 (S.D.=0.75) cm. Pure cavernous hemangioma is the predominant type of mitral hemangioma. Most of them are described as pedunculated or polypoid. Surgical excision appears to be curative. Recurrences have not been reported. Lymphocyte-rich cardiac hemangioma represents a peculiar type of hemangioma which should be included in the differential diagnosis of other vascular lesions.

Synchronous Hepatoblastoma, Neuroblastoma, and Cutaneous Capillary Hemangiomas: A Case Report.

Multiple synchronous tumors presenting in infancy raise concern for inherited or sporadic cancer predisposition syndromes, which include Beckwith-Wiedemann syndrome, familial adenomatous polyposis syndrome, and Li-Fraumeni syndrome. We report a case of a 7-month-old previously healthy male born following an in vitro fertilization-assisted twin pregnancy who presented with new-onset refractory shock, severe acidosis, and rapid decline over several hours. An autopsy revealed a ruptured liver involved by hepatoblastoma, an adrenal gland involved by neuroblastoma, and multiple cutaneous capillary hemangiomas. Standard genetic testing demonstrated that both twins were Gaucher disease (GD) carriers without evidence of other known cancer predisposition syndromes. This report describes a unique association of multiple synchronous tumors, which underscores the utility and importance of the pediatric autopsy. Moreover, given that the reported child was a GD carrier, the possibility the tumors were the result of a GD-mediated cancer-associated phenotype or an unrecognized sporadic clinical syndrome remains an unanswered, but intriguing, question worthy of further investigation.

Extensively Myxoid and Hyalinized Sinonasal Capillary Hemangiomas: A Clinicopathologic Study of 16 Cases of a Distinctive and Potentially Confusing Hemangioma Variant.

Capillary hemangiomas, the most common vascular tumors of the sinonasal region, are benign endothelial neoplasms, typically growing in an easily recognized lobular pattern. Some sinonasal capillary hemangiomas may show atypical features, such as high cellularity or mitotic activity, and represent more challenging diagnoses. Over the past several years we have seen in consultation a number of examples of sinonasal capillary hemangiomas displaying very striking stromal myxoid change and hyalinization, features that have received scant attention in the past. Available slides from 16 sinonasal capillary hemangiomas previously coded as showing such changes were retrieved from our archives. Submitting diagnoses included "query angiofibroma, rule out malignancy" (N=4), "vascular polyp, rule out malignancy" (N=3), "query malignant vascular tumor" (N=4), "sinonasal hemangiopericytoma" (N=1), and "benign vascular tumor" (N=1). Available radiographic studies often showed worrisome features. Grossly, the tumors ranged from 1.1 to 6.0 cm and appeared as ulcerated, vascular-appearing polyps. Microscopically, the tumors showed striking stromal myxoid change and/or hyalinization, which largely obscured the underlying lobular capillary arrangement. Within this myxohyaline matrix, a florid capillary proliferation was present, frequently with nonatypical mitotic activity. In some instances a branching, "hemangiopericytoma-like" vascular pattern was present in areas. The overall cellularity was low to moderate, and endothelial atypia or hyperchromatism was absent. Ulceration and thrombosis were frequently present. Immunostains to CD31, CD34, and SMA highlighted areas of lobular growth pattern inapparent on the routinely stained slides. Four tested cases were negative for androgen receptors and ß-catenin. Follow-up from 12 patients revealed no local recurrences or metastases. Awareness of that sinonasal capillary hemangioma may show these unusual stromal changes, and the use of ancillary immunohistochemistry to highlight its lobular growth pattern should allow its confident distinction from more aggressive endothelial tumors (eg, angiosarcoma) and from nonendothelial tumors, including nasopharyngeal angiofibroma, solitary fibrous tumor, and sinonasal hemangiopericytoma-like tumor.

Multifocal capillary hemangioma (hemangiomatosis) of the spleen.

BACKGROUND: The spleen is mainly affected by benign tumors that originate from the vascular endothelium. The most common is hemangioma, which presents as a small, localized lesion. Isolated diffuse hemangiomatosis of the spleen is a rare entity in which the entire splenic parenchyma is replaced by a proliferation of neoplastic blood vessels. Here we illustrate the case of a 26-year-old man presenting with splenomegaly due to diffuse hemangiomatosis of the white pulp who underwent a splenectomy. METHODS: Representative samples of the spleen were stained with hematoxylin and eosin, and immunohistochemical analysis was performed for Mib-1, CD20, CD30, CD15, CD34, CD31, CD8, factor VIII, D2-40, CD68PGM1, and LMP1. RESULTS: Macroscopically, the splenic parenchyma contained multiple, red-brown nodules ranging from 0.4 to 1.5 cm. Microscopically, the nodules were roundish and confluent with an angiomatoid appearance and high positivity for CD34 and factor VIII, while they were negative for D2-40. CONCLUSIONS: The differential diagnosis of splenic tumors includes lymphangioma, lymphangiomatosis, peliosis, littoral cell angioma, hemangioendothelioma, hamartoma, angiomatoid transformation of the spleen, and angiosarcoma. It is debated whether diffuse hemangiomatosis is a malformation of the postsinusoidal venous system or a slowly growing neoplasm arising from the splenic sinuses. The positivity of the cavernous vessels for CD8 seems to be in favor of the malformative nature of the tumor.

A placental chorionic villous mesenchymal core cellular origin for infantile haemangioma.

AIMS: To investigate the expression of the placental cell-specific associated proteins in infantile haemangioma (IH). METHODS: Immunohistochemical staining was used to investigate the expression of human chorionic gonadotrophin (hCG), human placental lactogen (hPL), human leucocyte antigen-G (HLA-G), cytokeratin 7 (CK7) and smooth muscle actin in paraffin-embedded sections of proliferating and involuted IHs. RESULTS: The proteins hCG and hPL were expressed by the endothelium but not the pericyte layer of proliferating IH, but these proteins were not detected in involuted lesions. There was no expression of CK7 and HLA-G in IH. CONCLUSIONS: The expression of hCG and hPL, but not CK7 or HLA-G, by the endothelium of proliferating IH supports a placental chorionic villous mesenchymal core cellular origin for IH rather than a trophoblast origin.

Biomarkers: important clues to the pathogenesis of infantile haemangioma and their clinical significance.

Infantile haemangioma is the most common tumour of infancy, yet the pathogensis of this lesion remains unknown and the predictable life cycle is poorly understood. Though much new information on infantile haemangioma has emerged over the past decade, researchers continue to debate the fundamental features; including cells of origin, nonrandom distribution, and mechanisms regulating the sometimes explosive growth and slow involution. The development of biomarkers has shed light on the pathogenesis and management of infantile haemangioma. Several useful biomarkers and their suggestions as to the aetiology of infantile haemangioma are reviewed. In addition, the application in clinical diagnosis and choice of treatment methods of infantile haemangioma is summarised.

Capillary hemangioma of the endometrium: a case report and review of the literature.

A 39-year-old woman with menorrhagia of 7 years' duration was found to have a capillary hemangioma of the endometrium. Initial diagnosis by curettage was considered questionable but was later confirmed at hysterectomy. A thorough search and review of the literature was performed.

Pulmonary hemangiomas of infancy and childhood: report of two cases and review of the literature.

Pulmonary hemangiomas are exceptionally rare in childhood and more so in infancy. They may involve the airways or the parenchyma, and may be localized or multifocal. We present two cases of pulmonary capillary hemangiomas. The first case is a localized form of capillary hemangioma that was resected from an 8-week-old infant with signs of respiratory distress. A computed tomography scan showed a cystic mass initially thought to be an intrapulmonary bronchogenic cyst. A segmental resection was performed and examination revealed a localized capillary hemangioma without cystic or cavernous features. The second case is an example of a multifocal capillary hemangioma from a 9-year-old child who presented clinically with clubbing of fingers and toes and radiologically had multiple discrete nodules localized to the right lung. The clinical and pathological features of the cases are discussed together with a review of the literature. The distinction from other vascular neoplasms of childhood is briefly described. Although rare, pulmonary hemangiomas should be entertained in the diagnosis of both solid and cystic intrapulmonary lesions of childhood and infancy.

Multifocal distribution of pulmonary capillary haemangiomatosis.

AIMS: We investigated a case of pulmonary capillary haemangiomatosis, a rare condition, to determine the extent of the pathological changes within the lungs. Systematic histological sampling has not previously been performed in this condition. METHODS AND RESULTS: A 52-year-old woman with a history of ischaemic cardiomyopathy suffered from repeated respiratory infections, which were attributed to chronic pulmonary congestion. She died suddenly of fulminant pulmonary thromboembolism. An autopsy was performed and lung tissue was sampled at multiple sites. Beside passive congestion, the lungs showed well-circumscribed areas containing proliferations of small capillaries infiltrating the pulmonary septa and the walls of otherwise normal blood vessels and bronchi. The most severely affected areas were found to be in the periphery of both lower lobes. A diagnosis of pulmonary capillary haemangiomatosis was made. CONCLUSIONS: This is the first case of pulmonary capillary haemangiomatosis in which systematic histological sampling has been performed. Mapping of lesions disclosed the multifocal distribution of pulmonary capillary haemangiomatosis in this patient.

Hemangioma of the testis: report of unusual occurrences of cavernous hemangioma in a fetus and capillary hemangioma in an older man.

We report two cases of hemangiomata of the testes which occurred in a 17-week-old fetus and a 73-year-old man. To our knowledge, these are the first reported cases of cavernous hemangioma of the testis in a fetus and capillary hemangioma of the testis in an older man. Although a hemangioma of the testis is rare, it should be considered in the differential diagnosis of a testicular tumor. Ann Diagn Pathol 5:80-83, 2001.

Histopathology of vascular lesions found in Kasabach-Merritt syndrome: review based on 13 cases.

We reviewed the histopathology of 13 cases of Kasabach-Merrit Syndrome (KMS). In 4 (31%) cases the predominant morphology was that of a tufted angioma (TA). Six (46%) cases were Kaposiform hemangioendotheliomas (KHE), and 3 (23%) cases showed an infantile (juvenile) hemangioma only. Immunostaining for CD34 and actin (HHF-35) was helpful in defining these types of hemangiomas. The TA was characterized by a proliferation of endothelial cells positive for CD34 with a minimal component of actin-positive cells. KHE showed a paucity of immunoreactive cells; only the luminal endothelial cells were positive for CD34. In three cases with the morphology of infantile hemangiomas, actin-positive cells outnumbered the CD34-positive cells. Our findings confirm the observation that the underlying vascular lesion in KMS is usually not an infantile hemangioma as was originally thought, but variants of hemangiomas such as TA and KHE (77% of 13 KMS cases). Infantile hemangioma was the phenotypic substrate of KMS in only 3 of 13 cases.

Sex hormone receptors of hemangiomas in children.

OBJECTIVE: To investigate whether or not estrogen receptor and other sex hormone receptors are present in hemangioma tissues of children. METHODS: Fifty-two specimens of hemangiomas were taken from 52 children. The specimens were doubly stained with hematoxylin-eosin and enzyme-linking affinity immunohistochemistry. The prepared tissue slides were observed under the microscope to search for estrogen receptors (ER), progestogen receptors (PR) and androgen receptors (AR) in all the cells. RESULTS: ER, PR and AR were detected in various kinds of hemangiomas. The mean positive cell rate of each sex hormone receptor in different hemangioma tissues revealed no significant distinction in statistics (P > 0.05). CONCLUSIONS: The results suggest that hemangiomas are one of the target tissues of estrogen. Estrogen, ER, PR, and AR may play an important role in the growth and development of hemangiomas.

High frequency of apoptosis in infantile capillary haemangioma.

Infantile capillary haemangioma (ICH) is a well-established clinicopathological entity which often regresses spontaneously. To elucidate the cause of spontaneous involution of ICH, the apoptotic and proliferative activities in seven cases of ICH were compared with those in five cases of lobular capillary haemangioma (LCH), using formalin-fixed paraffin-embedded tissue sections. The number of apoptotic cells detected by the modified in situ end-labelling method was significantly higher in ICH than in LCH, while the proliferative activities evaluated with mitosis and Ki-67 antigen expression did not differ significantly. Lewisy (Ley) antigen, an apoptosis-associated marker, was expressed in all cases of ICH but in none of LCH, while labelling for p53 protein and bcl-2 protein was almost completely negative in both tumours. These findings clearly demonstrate a much higher apoptotic activity in ICH than in LCH and suggest that apoptosis might be a cause of the spontaneous involution of ICH.

Expression of VE (vascular endothelial)-cadherin and other endothelial-specific markers in haemangiomas.

Haemangiomas are vascular tumours characterized by rapid growth and increased endothelial turnover. VE-cadherin is a recently discovered endothelial cell-specific cadherin located at intercellular junctions. In different types of epithelial tumours, cadherin expression is inversely correlated with invasiveness and metastatic dissemination. In this immunohistochemical study, VE-cadherin expression has been analysed in different types of haemangioma. VE-cadherin is highly expressed in endothelial cells of haemangiomas and is decreased, but still detectable, in some cases of haemangionendothelioma and angiosarcoma. The antigenic profile of most haemangioma cells was similar to that of normal endothelium. CD31, CD34, ICAM-1, von Willebrand factor, and VLA integrins were expressed in haemangioma endothelium; in addition, the major components of vascular basement membrane, namely fibronectin, collagen type IV, and laminin, were correctly expressed and organized. Surprisingly, a marked reactivity for the M form of laminin (merosin) was detected in the basement membranes of two juvenile capillary haemangiomas. Overall, this study shows that, with the exception of angiosarcoma and haemangionendothelioma, vascular tumours maintain most of the differentiation characteristics of normal endothelium. This encourages speculation that in these pathologies, abnormal endothelial proliferation is more related to the release of local factors than to an altered endothelial phenotype.