Adult cutaneous hemangiomas are composed of nonreplicating endothelial cells

Angiokeratoma corporis diffusum with severe acroparesthesia, an endothelial abnormality, and inconspicuous genetic findings

Angiokeratoma corporis diffusum (ACD) was long thought to be a specific dermal sign of Fabry disease (FD, X-linked alpha-galactosidase A [GLA] deficiency). However, other lysosomal storage diseases (LSDs) have also been identified as triggers of ACD. Generalized vasculopathy is an important pathogenetic factor in FD and may also lead to the acroparesthesia (AP) often predominant in FD. We report on an 85-year-old woman with ACD present since her youth and associated with severe AP. Ultrastructure of the dermal lesion showed no lysosomal involvement, but the absence of the basement membrane of the endothelial cells of the capillary vessels was noteworthy. Repeated analyses of the GLA gene revealed no evidence of FD. Whole-exome sequencing was negative for FD and other LSDs, and allowed us to also study FD-related intronic regions of the GLA gene. This is the first report of a patient with FD-like ACD with an endothelial abnormality, otherwise unexplained vasculopathy and severe AP, which are not due to FD or another LSD. Based on family history, another genetic, yet unidentified, defect may cause the disease in this patient. In unexplained ACD, extended genetic analysis is required to exclude particular pathogenic variants of the GLA gene and other genes.

Aberrant cytoplasmic connexin43 expression as a helpful marker in vascular neoplasms

BACKGROUND

Gap junctions consisting of connexins (Cx) are fundamental in controlling cell proliferation, differentiation, and cell death. Cx43 is the most broadly expressed Cx in humans and is attributed an important role in skin tumor development. Its role in cutaneous vascular neoplasms is yet unknown.

METHODS

Fifteen cases each of cutaneous angiosarcoma (cAS), Kaposi sarcoma (KS), and cherry hemangioma (CH) were assessed by immunohistochemistry for expression of Cx43. Expression pattern, intensity, and percentage of positively stained cells were analyzed. Solid basal cell carcinomas served as positive and healthy skin as negative controls.

RESULTS

Most cases of cAS presented with a strong Cx43 staining of almost all tumor cells, whereas endothelia of KS showed medium expression and CH showed mostly weak expression. In comparison with KS or cAS, the staining intensity of CH was significantly lower (P ≤ 0.001). All tissue sections of both cAS and KS were characterized by a mostly diffuse, cytoplasmic staining pattern of the vascular endothelia. None of those showed nuclear staining.

CONCLUSION

The high-to-intermediate expression of Cx43 observed in all cases of cAS and KS suggests that this Cx may play a role in the development of malignant vascular neoplasms and serve as a helpful diagnostic marker.

High frequency of GNA14, GNAQ, and GNA11 mutations in cherry hemangioma: a histopathological and molecular study of 85 cases indicating GNA14 as the most commonly mutated gene in vascular neoplasms

Cherry hemangioma is the most common hemangioma in adult life. Neoplastic and non-neoplastic theories had both been proposed for its pathogenesis, but its nature is still poorly understood. We noted a significant subset of anastomosing hemangiomas and congenital hemangiomas harbored a population of small capillaries surrounded by a perivascular hyaline layer, reminiscent of the vessels seen in cherry hemangioma. Both anastomosing hemangioma and congenital hemangioma harbor recurrent mutations in exon 5 of GNAQ and its paralogues. In this study, we analyzed 68 cherry hemangiomas and 17 cherry hemangioma-like hemangiomas exhibiting additional non-classical features including markedly dilated, cavernous vessels, and/or a deep component extending to the deep dermis. By Sanger sequencing, GNAQ, GNA11, and GNA14 exon 5 mutations were identified in 12, 4, and 32 cherry hemangiomas, respectively, and 5, 3, and 3 cherry hemangioma-like hemangiomas, respectively. MassARRAY analysis detected mutations (including exon 2 GNAQ^G48V mutations) in additional 8 cherry hemangiomas and 3 cherry hemangioma-like hemangiomas. Overall, the cherry hemangiomas and cherry hemangioma-like hemangiomas had equal GNA mutation rates (82%), and GNA14 and GNAQ mutations were present in approximately half of cherry hemangiomas and cherry hemangioma-like hemangiomas, respectively. All mutations were mutually exclusive. KRAS^G12V mutation was also detected in one cherry hemangioma-like hemangioma without GNA mutations. In summary, our study demonstrated recurrent GNA14/GNAQ/GNA11 mutations were present in the majority of this very common hemangioma and established its neoplastic nature. Our results also expanded the morphological spectrum of GNA-mutated hemangiomas to include tumors composed of cavernous-like vessels and indicated GNA14 was the most commonly mutated gene in vascular tumors.

Use of Targeted Next-Generation Sequencing to Identify Activating Hot Spot Mutations in Cherry Angiomas

Importance

Shared gene variants in benign-malignant process pairs, such as BRAF mutations common to benign nevi and melanoma, are associated with differing phenotypic manifestations. Study of gene mechanisms underlying cherry angioma may uncover previously unknown disease relationships.

Objective

To identify somatic mutations present in cherry angioma specimens by using targeted next-generation sequencing.

Design, Setting, and Participants

In a single-center case series, 10 formalin-fixed, paraffin-embedded cherry angioma specimens from biopsies performed at Massachusetts General Hospital in Boston from July 10, 2016, to January 23, 2018, were obtained and underwent sequencing across a panel of 323 genes most relevant to cancer. Somatic mutations were curated by excluding variants that were presumed to be germline or of low mapping quality.

Main Outcomes and Measures

Identification of somatic mutations associated with cherry angiomas.

Results

In 10 cherry angioma tissue samples originating from 6 female and 4 male patients with a median (range) age of 54 (26-79) years, 5 samples (50%) revealed somatic missense mutations in GNAQ (Q209H, Q209R, and R183G) and GNA11 (Q209H). Individually, these mutational hot spots are known to be involved in entities that include congenital and anastomosing hemangiomas, hepatic small-vessel neoplasms (Q209), port-wine stains, and Sturge-Weber syndrome (R183). Both hot spots are associated with blue nevi, melanoma associated with blue nevus, and uveal melanoma.

Conclusions and Relevance

In this case series study, the high prevalence of 5 known genetic drivers within the benign cherry angioma entity appears to support the context-dependent role of gene alterations in both benign and malignant proliferations from various cellular origins.

Segmental cherry angiomas associated with extragenital lichen sclerosus: a report of two cases

Cherry angiomas (Campbell de Morgan spots) are common acquired red skin papules composed of dilated capillary loops, usually of unknown aetiology. Extragenital lichen sclerosus (LS) presents as porcelain-white scaly atrophic lesions with or without genital involvement. We report two cases of segmental multiple cherry angiomas in association with extragenital LS. Two unrelated women, aged 46 and 66 years, presented with extragenital LS affecting their axillae and lower abdomen. During the examination, both patients were noted to have several hundred red skin papules in a segmental distribution, affecting the left thigh and flank of one woman, and the right abdomen and back of the other. Clinically and histologically, the papules were consistent with cherry angiomas. The striking segmental distribution of multiple cherry angiomas may be due to genetic mosaicism; however, segmental Fabry disease was excluded by sequence analysis of the α-galactosidase A gene. Any causal link between cherry angiomas and LS remains uncertain.

Down-regulation of mir-424 contributes to the abnormal angiogenesis via MEK1 and cyclin E1 in senile hemangioma: its implications to therapy

Background

Senile hemangioma, so-called cherry angioma, is known as the most common vascular anomalies specifically seen in the aged skin. The pathogenesis of its abnormal angiogenesis is still unclear.

Methodology/Principal Findings

In this study, we found that senile hemangioma consisted of clusters of proliferated small vascular channels in upper dermis, indicating that this tumor is categorized as a vascular tumor. We then investigated the mechanism of endothelial proliferation in senile hemangioma, focusing on microRNA (miRNA). miRNA PCR array analysis revealed the mir-424 level in senile hemangioma was lower than in other vascular anomalies. Protein expression of MEK1 and cyclin E1, the predicted target genes of mir-424, was increased in senile hemangioma compared to normal skin or other anomalies, but their mRNA levels were not. The inhibition of mir-424 in normal human dermal microvascular ECs (HDMECs) using specific inhibitor in vitro resulted in the increase of protein expression of MEK1 or cyclin E1, while mRNA levels were not affected by the inhibitor. Specific inhibitor of mir-424 also induced the cell proliferation of HDMECs significantly, while the cell number was decreased by the transfection of siRNA for MEK1 or cyclin E1.

Conclusions/Significance

Taken together, decreased mir-424 expression and increased levels of MEK1 or cyclin E1 in senile hemangioma may cause abnormal cell proliferation in the tumor. Senile hemangioma may be the good model for cutaneous angiogenesis. Investigation of senile hemangioma and the regulatory mechanisms of angiogenesis by miRNA in the aged skin may lead to new treatments using miRNA by the transfection into senile hemangioma.

Hemangioma rubi no couro cabeludo

O hemangioma rubi (HR) é dermatose de origem vascular extremamente freqüente, acometendo mais de 75% da população acima de 70 anos de idade. Em geral compõe-se de lesões múltiplas,localizadas predominantemente no alto do tronco e braços. Clinicamente é caracterizado por lesões que variam desde máculas puntiformes até lesões papulosas com cinco milímetros de diâmetro. As mais novas são vermelhas, em tons vivos, e as mais antigas podem ser azuladas. O HR é de etiologia desconhecida. Histologicamente chama atenção uma neoformação de vasos capilares, que se tornam dilatados e com fenestrações em suas paredes. A membrana basal está muito espessada e existe abundante estroma de colágeno entre os vasos. O presente trabalho demonstra a alta incidência do HR no couro cabeludo Em amostra de 171 pacientes, sendo 85 homens e 86 mulheres, o autor observou que 123 deles (72%) tinham HR no couro cabeludo, localização em que o HR nunca foi descrito na literatura.

Epithelioid hemangioendothelioma of the liver: a clinicopathologic study of 137 cases

BACKGROUND

Epithelioid hemangioendothelioma (EHE) is a rare neoplasm of vascular origin that occurs in the liver and other organs; its etiology is unknown.

METHODS

The authors analyzed the clinicopathologic and immunohistochemical features of 137 patients with EHE of the liver in an attempt to identify features that might predict tumor behavior. To their knowledge, this article represents the largest series reported from one institution.

RESULTS

Patients were ages 12-86 years; 84 (61%) were females and 53 (39%) were males. They presented with nonspecific symptoms such as right upper quadrant pain or weight loss. Macroscopically, the tumors usually were multiple. They typically were white, firm to hard, and ranged in size from 0.2-14 cm. Histologically, the tumors were comprised of dendritic and epithelioid cells that often contained vacuoles representing intracellular lumina. The stroma was fibrous, with myxohyaline areas. Immunohistochemically, all tumors were positive for at least one endothelial marker (factor VIII-related antigen [FVIII-RAg], CD34, and/or CD31). Treatment modalities included hepatic resection or transplantation. Although the metastatic rate in this series was 27%, the prognosis is considered much more favorable than that of other hepatic malignancies. Twenty-six patients (43%) survived > or = 5 years; 2 patients were alive and well at last follow-up after 23 and 27 years, respectively. Twenty-six of 60 patients (43%) died of their disease, 1 of whom died 28 years after discovery of her tumor. In an attempt to predict behavior of the tumor, several histologic parameters were evaluated using univariate analysis. No significant correlation was found with mitoses, Glisson's capsule infiltration, or nuclear atypia. High cellularity was significantly correlated with a poor clinical outcome (P = 0.00012), whereas the association with tumor necrosis approached significance (P = 0.057).

CONCLUSIONS

EHE is a very rare clinical entity. The key to diagnosis is the demonstration of cells containing FVIII-RAg. The histology of the tumor, including nuclear pleomorphism and the mitotic count, are of no value in predicting clinical outcome. High cellularity most likely is the most significant parameter predicting an unfavorable prognosis in EHE because mitotic counts often are quite low in both low grade and aggressive tumors. Further studies are needed to identify the factors responsible for the apparent dissociation between the clinical behavior and biologic characteristics of this tumor.

Cutaneous vascular proliferation. Part II. Hyperplasias and benign neoplasms

This second part of our review about vascular proliferations summarizes the clinicopathologic features of the cutaneous vascular hyperplasias and benign neoplasms. Hyperplasias comprise a heterogeneous group of vascular proliferations that eventually show a tendency to regression. Angiolymphoid hyperplasia with eosinophilia is included within the group of hyperplasias because of its historical denomination and its reactive nature, probably as a consequence of an arteriovenous shunt, although usually the lesions do not regress. Pyogenic granuloma, bacillary angiomatosis, intravascular papillary endothelial hyperplasia, and pseudo-Kaposi's sarcoma qualify as vascular hyperplasias because they regress when the stimulus that initiated them is removed. Benign neoplasms form a large group of hemangiomas with distinctive clinicopathologic characteristics, although some of them are of recent description and may produce diagnostic difficulties. We classified cutaneous benign vascular neoplasms according to their cell lineage of differentiation, for example, endothelial, glomus cell, and pericytic differentiation. Subsequent categories are established according to the size of the involved vessels (capillaries, venules and arterioles, or veins and arteries) or the nature of the proliferating vessels (blood or lymphatic vessels). Capillary and cavernous hemangiomas have been the terms classically used to name the most common variants of benign vascular neoplasms (i.e., infantile hemangiomas), but they are not the most appropriate denominations for these lesions. First, these names are not contrasting terms. Furthermore, most of the socalled "cavernous" hemangiomas are not hemangiomas (neoplasms) at all, but venous malformations. The most important conceptual issue is that, at any point in time, a particular hemangioma has its own histopathologic pattern throughout the depth of the lesion. For these reasons, we classified hemangiomas into superficial and deep categories. Some of the lesions reviewed have been recently described in the literature, and they may histopathologically mimic lesions of Kaposi's sarcoma; these include targetoid hemosiderotic hemangioma, microvenular hemangioma, tufted hemangioma, glomeruloid hemangioma, kaposiform hemangioendothelioma, spindle-cell hemangioendothelioma, and benign lymphangioendothelioma. In each of these lesions, we update and emphasize those clinical and histopathologic features that are helpful for differential diagnosis with lesions of authentic Kaposi's sarcoma in any of its three stages of development (patch, plaque, or nodule).

Primary epithelioid hemangioendothelioma of the brain

Epithelioid hemangioendothelioma is an uncommon form of endothelial neoplasm, one of intermediate-grade malignancy and relatively favorable prognosis. Herein we report the third and fourth cases described in the central nervous system and compare their clinical and pathologic properties with those arising at systemic sites. Both patients presented with signs and symptoms of a mass lesion with seizures present in both cases. Imaging studies revealed well-demarcated mass lesions with surrounding edema. Gross total removal was accomplished surgically in both cases One case was partially cystic and nodular; the other was firm, focally gritty, and cartilaginous in appearance. Histologically they were identical to hemangioendotheliomas of other locales: multinodular neoplasms with regional variation in cellularity, cords and clusters of epithelioid cells with variable attempts at lumen formation, and spindled cells associated with a fibromyxoid matrix. Immunohistochemical stains confirmed the endothelial natures of the cells. These cases and those previously reported were treated with surgical excision. The few patients described have ranged in age from infants to older adults. Some patients have had residual neurologic defects, but no deaths due to tumor have been reported.

Monoclonal antibody Ki-67: its use in histopathology

Monoclonal antibody Ki-67 is a reliable and easy means of accurately assessing the growth fraction of human neoplasms. Although the number of long-term follow-up studies is limited, it does appear to provide valuable prognostic information particularly in lymphoproliferative disease. Since the estimation of growth fraction is only one factor influencing tumour behaviour it would be naive to believe that measurement of this parameter alone, no matter how accurately, would provide the clinician with definitive prognostic information for all tumours. The antibody is also of use in research, providing a means of measuring proliferative activity in a variety of conditions besides malignancy, and may prove of value in monitoring tumour response to established and trial therapies.

Cyclic adenosine monophosphate levels and the function of skin microvascular endothelial cells

The maintenance of the normal epithelioid morphology of human dermal microvascular endothelial cells (MEC) grown in vitro depends strongly on the presence of factors that increase intracellular levels of cyclic AMP. Complete removal of dibutyryl cAMP and isobutylmethylxanthine (IMX) from the growth medium results in a progressive transition from an epithelioid to a spindle-shaped cell line. This transition cannot be reversed by the readdition of dibutyryl cAMP and IMX to the growth medium or by addition of agonists that increase cAMP levels. Spindle-shaped MEC lose the ability to express Factor VIII rAG and DR antigens and to bind peripheral blood mononuclear leukocyte (PBML). Ultrastructural analyses of transitional cells and spindle-shaped cells show decreased numbers of Weibel-Palade bodies in transitional cells and their complete absence in spindle-shaped cells. Interferon-gamma alters several functional properties of both epithelioid and spindle-shaped cells. In the absence of dibutyryl cAMP it accelerates the transition from epithelial to spindle-shaped cells, whereas in the presence of cyclic AMP interferon-gamma increases the binding of PBMLs to both epithelioid and spindle-shaped MEC and the endocytic activity of the endothelial cells. These results suggest that cyclic AMP is an important second messenger in the maintenance of several key functions of microvascular endothelial cells. Factors that influence the levels of this messenger in vivo can be expected to influence the angiogenic and immunologic functions of the microvasculature.