GLUT1: a newly discovered immunohistochemical marker for juvenile hemangiomas

Head and Neck Vascular Anomalies in Children

Craniomaxillofacial vascular anomalies encompass a diverse and complex set of pathologies that may have a profound impact on pediatric patients. They are subdivided into vascular tumors and vascular malformations depending on biological properties, clinical course, and distribution patterns. Given the complexity and potential for leading to significant functional morbidity and esthetic concerns, a multidisciplinary approach is generally necessary to optimize patient outcomes. This article reviews the etiology, clinical course, diagnosis, and current management practices related to vascular anomalies in the head and neck.

Congenital Vascular and Lymphatic Diseases

Over the past several centuries, the integration of contemporary medical techniques and innovative technologies, like genetic sequencing, have played a pivotal role in enhancing our comprehension of congenital vascular and lymphatic disorders. Nonetheless, the uncommon and complex characteristics of these disorders, especially considering their formation during the intrauterine stage, present significant obstacles in diagnosis and treatment. Here, we review the intricacies of these congenital abnormalities, offering an in-depth examination of key diagnostic approaches, genetic factors, and therapeutic methods.

Is endoscopic resection a useful technique for a cavernous sinus sellar cavernoma? A case report and literature review

BACKGROUND

Cavernous sinus cavernous malformations (CSCMs) is a vascular malformation of the cavernous sinus. Nowadays, there is an increasing preference to withhold using the terms cavernoma or cavernous hemangioma in order to stop considering these lesions as vascular neoplasms. These lesions are highly vascularized making surgical resection a challenge, mainly in endoscopic approaches. We present a case of this tumor treated in our institution with an endoscopic endonasal approach and incomplete resection. Because of the strenuous resection through this approach, we systematically reviewed the reported endoscopic cases of CSCMs to determine their intraoperative complications, results and tumor features.

METHODS

Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, one database (PubMed) and crossed references were queried for CSCMs from 1948 to 2020. Data regarding demographic features, clinical presentation, MRI features, surgical results and overall pathology features extracted.

RESULTS

Eighteen patients were selected (including our case). The mean age was 50.4 ± 14 years. Pituitary dysfunction and cavernous sinus nerve compression were the most reported symptoms. Only five cases (27%) reported a gross total resection (GTR) through endoscopic endonasal approach. Intraoperative bleeding was the most frequent intraoperative complication.

CONCLUSION

We present a comprehensive analysis of every reported CSCM treated through endoscopic approach. Partial or subtotal resection are the most used techniques because of the intraoperative bleeding and the adherence to surrounding structures. Radiotherapy is a very good option for patients with incomplete resections.

Itraconazole Oral Solution for Infantile Complicated Hemangioma with Double Lesions on the Skin and One Inside the Liver

An infantile hemangioma is a congenital benign tumor formed by the proliferation of vascular cells during the embryonic stage. It is more common in the skin but can also occur in the mucous membranes, liver, brain and muscle. Hepatic hemangioma appears to be a benign tumor; however, it may lead to poor outcomes because of severe complications, such as high-output cardiac failure. The main treatment of hepatic hemangioma in infants is oral drugs, such as propranolol and glucocorticoids, but the clinical response is not always satisfactory. We describe a rare case of a 2-month-old boy who presented with infantile cutaneous and hepatic hemangiomas. By using dermoscopy and observations of the abdominal color Doppler ultrasound, after 9 months of oral treatment with itraconazole solution, the infantile cutaneous hemangioma complicated with hepatic hemangioma was eventually cured. There was no liver or kidney function damage during the whole treatment period. Itraconazole oral solution for the treatment of infantile cutaneous hemangioma complicated with hepatic hemangioma showed good efficacy, compliance, and safety in this case.

Management of Neonatal Hepatic Hemangiomas: A Single-Center Experience Focused on Challenging Cases

Background: Management of hepatic hemangioma (HH) in infancy ranges from close monitoring to surgical resection. We analyzed the clinical characteristics and outcomes of HH according to its treatment options, with particular focus on challenging cases. Methods: Data of patients diagnosed with HHs in their first year of life and followed up for at least 1 year were retrospectively reviewed and divided into treatment and observation groups. Serial imaging results, serum alpha-fetoprotein (AFP) levels, medications, and clinical outcomes were compared. The detailed clinical progress in the treatment group was reviewed separately. Results: A total of 87 patients (75 in the observation group and 12 in the treatment group) were included. The median HH size at the initial diagnosis and the maximum size were significantly larger in the treatment group than the observation group (2.2 [0.5-10.3] cm vs. 1.0 [0.4-4.0] cm and 2.1 [0.7-13.2] vs. 1.1 [0.4-4.0], respectively; all p < 0.05]. The median initial and last serum AFP levels were significantly higher in the treatment group than in the observation group (76,818.7 vs. 627.2 and 98.4 vs. 8.7, respectively; all p < 0.05). Serum AFP levels in both groups rapidly declined during the first 3 months of life and were almost undetectable after 6 months. Among the challenging cases, a large (14 × 10 × 6.5 cm sized) focal HH was successfully treated using stepwise medical-to-surgical treatment. Conclusions: Patients with large HH and mild symptoms can be treated using stepwise pharmacotherapy. More aggressive surgical treatment of tumors unresponsive to initial pharmacotherapy may help shorten the treatment period and improve outcomes.

Interdisciplinary Management of Vascular Anomalies in the Head and Neck

Vascular anomalies in the head and neck area are usually rare diseases and pose a particular diagnostic and therapeutic challenge. They are divided into vascular tumours and vascular malformations. A distinction is made between benign tumours, such as infantile haemangioma, and rare malignant tumours, such as angiosarcoma. Vascular malformations are categorised as simple malformations, mixed malformations, large vessel anomalies and those associated with other anomalies. Treatment is interdisciplinary and various modalities are available. These include clinical observation, sclerotherapy, embolisation, ablative and coagulating procedures, surgical resection and systemic drug therapy. Treatment is challenging, as vascular anomalies in the head and neck region practically always affect function and aesthetics. A better understanding of the genetic and molecular biological basis of vascular anomalies has recently led to clinical research into targeted drug therapies. This article provides an up-to-date overview of the diagnosis, clinic and treatment of vascular anomalies in the head and neck region.

Infantile Hemangiomas Lose Vascular Endothelial Cadherin During Involution: Potential Role in Cell Death?

Background

Infantile hemangiomas (IHs) are benign endothelial cell (EC) tumors that undergo a predictable natural history, with rapid proliferation, stabilization, and involution. However, mechanisms regulating these transitions are not well understood. We have observed loss of vascular endothelial cadherin (VECAD) in involuting/involuted IHs. VECAD plays a critical role in angiogenesis, cell cycle progression, and EC survival. We hypothesize that loss of VECAD is associated with apoptosis occurring during IH involution.

Methods

Resected IH samples were clinically categorized as proliferating (n = 4), stable (n = 4), or involuting/involuted (n = 5). Neonatal dermal tissues were used as controls (n = 5). Immunohistochemistry was conducted on sectioned specimens using antibodies against EC markers VECAD and CD31. Apoptosis was assessed with terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay.

Results

CD31 signal intensity in proliferating, stable, and involuting/involuted IH ECs was unchanged relative to each other and to control ECs. VECAD signal significantly and progressively diminished as IHs progressed from proliferation to involution. Involuting/involuted IHs had significantly reduced VECAD expression compared with control ECs (P < 0.0001), proliferating IHs (P < 0.0001), and stable IHs (P < 0.001). As expected, the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling-positive ECs was significantly higher in involuting/involuted IHs (P < 0.05) relative to control ECs and proliferating IHs.

Conclusions

Loss of VECAD expression in IH endothelium corresponded to IH involution and increased apoptosis. It is unclear whether loss of VECAD is causative of IH involution; further studies are needed to elucidate the role of VECAD function in EC survival.

Capillary malformations

Capillary malformation (CM), or port wine birthmark, is a cutaneous congenital vascular anomaly that occurs in 0.1%-2% of newborns. Patients with a CM localized on the forehead have an increased risk of developing a neurocutaneous disorder called encephalotrigeminal angiomatosis or Sturge-Weber syndrome (SWS), with complications including seizure, developmental delay, glaucoma, and vision loss. In 2013, a groundbreaking study revealed causative activating somatic mutations in the gene (GNAQ) encoding guanine nucleotide-binding protein Q subunit α (Gαq) in CM and SWS patient tissues. In this Review, we discuss the disease phenotype, the causative GNAQ mutations, and their cellular origin. We also present the endothelial Gαq-related signaling pathways, the current animal models to study CM and its complications, and future options for therapeutic treatment. Further work remains to fully elucidate the cellular and molecular mechanisms underlying the formation and maintenance of the abnormal vessels.

Infantile hemangioma: the common and enigmatic vascular tumor

Infantile hemangioma (IH) is a benign vascular tumor that occurs in 5% of newborns. The tumor follows a life cycle of rapid proliferation in infancy, followed by slow involution in childhood. This unique life cycle has attracted the interest of basic and clinical scientists alike as a paradigm for vasculogenesis, angiogenesis, and vascular regression. Unanswered questions persist about the genetic and molecular drivers of the proliferating and involuting phases. The beta blocker propranolol usually accelerates regression of problematic IHs, yet its mechanism of action on vascular proliferation and differentiation is unclear. Some IHs fail to respond to beta blockers and regrow after discontinuation. Side effects occur and long-term sequelae of propranolol treatment are unknown. This poses clinical challenges and raises novel questions about the mechanisms of vascular overgrowth in IH.

Recent advances in nanomaterial-driven strategies for diagnosis and therapy of vascular anomalies

Nanotechnology has demonstrated immense potential in various fields, especially in biomedical field. Among these domains, the development of nanotechnology for diagnosing and treating vascular anomalies has garnered significant attention. Vascular anomalies refer to structural and functional anomalies within the vascular system, which can result in conditions such as vascular malformations and tumors. These anomalies can significantly impact the quality of life of patients and pose significant health concerns. Nanoscale contrast agents have been developed for targeted imaging of blood vessels, enabling more precise identification and characterization of vascular anomalies. These contrast agents can be designed to bind specifically to abnormal blood vessels, providing healthcare professionals with a clearer view of the affected areas. More importantly, nanotechnology also offers promising solutions for targeted therapeutic interventions. Nanoparticles can be engineered to deliver drugs directly to the site of vascular anomalies, maximizing therapeutic effects while minimizing side effects on healthy tissues. Meanwhile, by incorporating functional components into nanoparticles, such as photosensitizers, nanotechnology enables innovative treatment modalities such as photothermal therapy and photodynamic therapy. This review focuses on the applications and potential of nanotechnology in the imaging and therapy of vascular anomalies, as well as discusses the present challenges and future directions.

KLF2 Orchestrates Pathological Progression of Infantile Hemangioma through Hemangioma Stem Cell Fate Decisions

Infantile hemangioma (IH) is the most prevalent vascular tumor during infancy, characterized by a rapid proliferation phase of disorganized blood vessels and spontaneous involution. IH possibly arises from a special type of multipotent stem cells called hemangioma stem cells (HemSCs), which could differentiate into endothelial cells, pericytes, and adipocytes. However, the underlying mechanisms that regulate the cell fate determination of HemSCs remain elusive. In this study, we unveil KLF2 as a candidate transcription factor involved in the control of HemSCs differentiation. KLF2 exhibits high expression in endothelial cells in proliferating IH but diminishes in adipocytes in involuting IH. Using a combination of in vitro culture of patient-derived HemSCs and HemSCs implantation mouse models, we show that KLF2 governs the proliferation, apoptosis, and cell cycle progression of HemSCs. Importantly, KLF2 acts as a crucial determinant of HemSC fate, directing their differentiation toward endothelial cells while inhibiting adipogenesis. Knockdown of KLF2 induces a proadipogenic transcriptome in HemSCs, leading to impaired blood vessel formation and accelerated adipocyte differentiation. Collectively, our findings highlight KLF2 as a critical regulator controlling the progression and involution of IH by modulating HemSC fate decisions.

Management of Midfacial and Skull Vault Osseous Vascular Lesions

There continuous to be widespread misuse of nomenclature used to described vascular anomalies, This is even more pronounced in the case of intra-osseous lesions. Bone involvement is more common with vascular malformations and extremely rare in haemangiomas. An accurate diagnosis is mandatory for tailored management and often based on a thorough history, clinical examination, and cross-sectional imaging. Surgery remains the main stay for the management of symptomatic venous malformations. Embolisation with or without surgery is the main stay for arteriovenous malformations. Virtual surgical planning, with surgical guides and patient specific implants help achieve predictably excellent results.

Infantile hemangioma in a subadult Chinese pangolin: a case report

BACKGROUND

Hemangiomas are a relatively common type of tumor in humans and animals. Various subtypes of hemangiomas have been described in the literature. The classification methods for hemangiomas differ between human and veterinary medicine, and the basis for tumor classification can be found in the literature.

CASE PRESENTATION

This study describes a tumor in the subcutaneous tissue of the right dorsum of an artificially rescued juvenile Chinese pangolin. Computed tomography (CT) examination yielded the preliminary diagnosis of a vascular malformation, and surgery was performed to resect the tumor. Histopathological examination showed that the tumor mainly was consisted of adipose tissue, capillaries, and spindle cells in the fibrous stroma. Immunohistochemistry showed the positive expression of CD31, CD34, α-SMA, GLUT1 and WT-1 in the tumor tissue, and the tumor was eventually diagnosed as an infantile haemangioma.

CONCLUSION

The final diagnosis of infantile hemangioma was depended on the histopathological immunohistochemical and CT examination of the neoplastic tissue. This is the first report of infantile hemangioma in a critically endangered species Chinese pangolin.

[Intraosseous cavernous hemangioma of the middle turbinate. Clinical cases]

Intraosseous vascular pathology of the turbinates is extremely rare in the practice of an otorhinolaryngologist and can be presented in various histopathological variants. The article presents two clinical cases in which an intraosseous cavernous hemangioma was hidden under the mask of a hypertrophied middle turbinate. The final diagnosis was established by the results of histological examination. The analysis of these clinical cases indicates that, despite the low prevalence, atypical clinical and CT picture, intraosseous formations of the nasal cavity can be of a vascular nature and certainly require a comprehensive examination, including CT, CT with contrast and/or MRI of the nose and paranasal sinuses. These clinical observations indicate that preliminary embolization of feeding vessels before surgical treatment is not required.

Global research trends of infantile hemangioma: A bibliometric and visualization analysis from 2000 to 2022

Background

Infantile hemangioma (IH) has received global attention, resulting in a significant volume of literature. However, there is a lack of bibliometric analyses specifically focusing on IH publications. This study aims to fill this gap by conducting a comprehensive analysis of IH publications, investigating their characteristics, contribution distribution, and developmental trends. By enhancing our understanding of IH and identifying potential research topics and collaborators, this study will contribute to the advancement of the field.

Methods

A total of 4333 articles and reviews on IH were collected from the Web of Science (WoS) database, spanning the years 2000-2022. The study encompassed a comprehensive analysis of IH publications, evaluating their quantity and quality. Additionally, we profiled publishing groups based on country, institution, author publication records, and collaboration networks. Lastly, we identified and summarized the prominent research topics.

Results

Annual publications on IH have increased over the past 20 years. The United States has the highest number of publications and the highest total number of citations. Pediatric Dermatology was the most influential journal in the IH field. The citation analysis indicated that the articles published by Léauté-Labrèze in 2008 had the highest number of citations. The articles published by North PE in 2000 and Boye E in 2001 laid a certain research foundation for this field. Concerning institutions, most of the cooperative relationships were established in the same country/region. The United States has the largest number of scientific research institutions and IH researchers, leading most of the cross-country collaboration. The University of California, San Francisco, Medical College of Wisconsin, Harvard University, and Shanghai Jiaotong University were the research centers that published the most IH-related research. Frieden IJ, Mulliken JB, and Drolet BA were the top three most influential authors. Frieden IJ, Garzon MC, and Mulliken JB were the top three authors with the most cited frequency. In addition, keywords and keyword co-occurrence networks prompted that the pathological mechanism of IH, clinical analysis, and other vascular anomalies are research hotspots. Analysis of trending topics suggests that research on IH has evolved from treatment-focused studies towards investigations of other vascular diseases and a series of clinical case studies. Currently, clinical case studies receive the most attention in the field.

Conclusions

This comprehensive bibliometric study provides a thorough analysis of post-2000 publications in the field of IH, offering insights into current research trends for the first time. The findings suggest that future investigations will continue to prioritize understanding IH mechanisms, treatment approaches, and treatment evaluation. Furthermore, the exploration of other vascular diseases and the inclusion of clinical case studies are expected to contribute to advancements in IH clinical practice. By identifying potential collaborators, partner institutions, and new research avenues, this study offers valuable guidance for future in-depth research on IH.

Cutaneous vascular tumors: an updated review

Cutaneous vascular tumors constitute a heterogeneous group of entities that share overlapping morphologic and immunohistochemical features, which can be diagnostically challenging for pathologists and dermatopathologists. Our understanding and knowledge of vascular neoplasms have improved over time, resulting in both a refinement of their classification by the International Society for the Study of Vascular Anomalies (ISSVA) and an improvement in the accurate diagnosis and clinical management of vascular neoplasms. This review article aims to summarize the updated clinical, histopathological, and immunohistochemical characteristics of cutaneous vascular tumors, as well as to highlight their associated genetic mutations. Such entities include infantile hemangioma, congenital hemangioma, tufted angioma, spindle cell hemangioma, epithelioid hemangioma, pyogenic granuloma, Kaposiform hemangioendothelioma, retiform hemangioendothelioma, pseudomyogenic hemangioendothelioma, Kaposi sarcoma, angiosarcoma, and epithelioid hemangioendothelioma.

Infantile Hemangioma: A Cross-Sectional Observational Study

(1) Background: With an incidence of 4-10%, infantile hemangiomas (IH) are the most encountered benign tumors in infancy. Low birth weight (LBW), prematurity, female sex, multiple gestations, and family history of IH are some of the statistically proven risk factors for developing IH. The aim of our study was to evaluate the prevalence of IH in our clinic and its connection to maternal and perinatal factors. (2) Methods: We conducted a cross-sectional study, over three years (2020-2022), at the Clinical Hospital of Obstetrics and Gynecology, "Prof. Dr. P. Sârbu", in Bucharest, Romania. (3) Results: During this period, 12,206 newborns were born and we identified 14 infants with infantile hemangioma. In our study, the prevalence of infantile hemangioma was 0.11%. The prevalence of IH in pregnancies obtained through in vitro fertilization was 1%, in twin pregnancies it was 2.27%, and in those with placenta previa, it was 4.16%. (4) Conclusions: Our findings provide a solid image of the prevalence of IH in our country and underline that the development of IH is strongly connected to maternal and perinatal variables, such as: preterm newborns, in vitro fertilization, high blood pressure, anemia, hypothyroidism, placenta previa, and twin pregnancy.

Pathological angiogenesis: mechanisms and therapeutic strategies

In multicellular organisms, angiogenesis, the formation of new blood vessels from pre-existing ones, is an essential process for growth and development. Different mechanisms such as vasculogenesis, sprouting, intussusceptive, and coalescent angiogenesis, as well as vessel co-option, vasculogenic mimicry and lymphangiogenesis, underlie the formation of new vasculature. In many pathological conditions, such as cancer, atherosclerosis, arthritis, psoriasis, endometriosis, obesity and SARS-CoV-2(COVID-19), developmental angiogenic processes are recapitulated, but are often done so without the normal feedback mechanisms that regulate the ordinary spatial and temporal patterns of blood vessel formation. Thus, pathological angiogenesis presents new challenges yet new opportunities for the design of vascular-directed therapies. Here, we provide an overview of recent insights into blood vessel development and highlight novel therapeutic strategies that promote or inhibit the process of angiogenesis to stabilize, reverse, or even halt disease progression. In our review, we will also explore several additional aspects (the angiogenic switch, hypoxia, angiocrine signals, endothelial plasticity, vessel normalization, and endothelial cell anergy) that operate in parallel to canonical angiogenesis mechanisms and speculate how these processes may also be targeted with anti-angiogenic or vascular-directed therapies.

Current concepts of vascular anomalies

Vascular anomalies encompass a variety of malformations and tumors that can result in severe morbidity and mortality in both adults and children. Advances have been made in the classification and diagnosis of these anomalies, with the International Society for the Study of Vascular Anomalies establishing a widely recognized classification system. In recent years, notable progress has been made in genetic testing and imaging techniques, enhancing our ability to diagnose these conditions. The increasing sophistication of genetic testing has facilitated the identification of specific genetic mutations that help treatment decisions. Furthermore, imaging techniques such as magnetic resonance imaging and computed tomography have greatly improved our capacity to visualize and detect vascular abnormalities, enabling more accurate diagnoses. When considering reconstructive surgery for facial vascular anomalies, it is important to consider both functional and cosmetic results of the procedure. Therefore, a comprehensive multidisciplinary approach involving specialists from dermatology, radiology, and genetics is often required to ensure effective management of these conditions. Overall, the treatment approach for facial vascular anomalies depends on the type, size, location, and severity of the anomaly. A thorough evaluation by a team of specialists can determine the most appropriate and effective treatment plan.

Apelin Receptor Can Act as a Specific Marker and Promising Therapeutic Target for Infantile Hemangioma

Infantile hemangioma (IH), the most common benign tumor in infancy, is generally sensitive to propranolol treatment. However, the challenge remains because resistance or recurrence could occur in some patients, and the mechanism or target of propranolol remains unknown. Therefore, advancement in the drug development is needed. In this study, we explored whether apelin receptor (APJ) can become a candidate target. We found that APJ is expressed only in endothelial cells of IH (HemECs) but not in other vascular anomalies, and its antagonist, ML221, can negatively regulate cellular viability and functions of HemECs. This inhibitory effect could be replicated in a murine hemangioma model. Importantly, in vitro experiments also indicated that ML221 failed to affect the proliferation or angiogenesis of normal endothelial cells or APJ-knockout HemECs. Through analysis of the phosphoantibody microarray data, ML221 was revealed to have an inhibitory effect on HemECs by suppressing the activation of mitogen-activated protein kinase/extracellular signal-regulated kinase pathway. These results verified the distinctive expression of APJ in IH and specific inhibition of HemEC activity caused by ML221. In addition, APJ was also detected in propranolol-resistant IH. Collectively, we propose that APJ can act as a specific marker and a promising therapeutic target for IH, which will facilitate further drug development.

Our experience with propranolol for infantile hemangioma

BACKGROUND/OBJECTIVES

The most frequent benign vascular tumor in children is infantile hemangioma (IH). For severe IHs, propranolol has become the first-line Treatment. Despite the fact that several studies have comprehensive therapy regimens, including the best time to start Treatment, dosage, visit frequency, and treatment duration, there is still controversy about the best time to start and stop propranolol medication.

METHODS

Between January 2016 and February 2019, dermatologists experienced hemangioma treatment and recommended propranolol treatment for 232 IHs. A total of 90 patients completed the treatment process after undergoing a color Doppler ultrasound test.

RESULTS

Propranolol uniquely affects each IH. Ninety patients were divided into two groups in this study: entire regression (n = 40) and partial regression (n = 50). The entire regression group's initial treatment period (4.3 ± 2.97 months) was substantially shorter than the partial regression group's (5.2 ± 4.57 months) (p < 0.05). Between the entire regression group (23.4 ± 12.8 months) and the partial regression group (24.5 ± 16.6 months), there was no significant difference in time to reduce propranolol. The partial regression group (32.9 ± 25.3month) had a lengthier treatment course than the entire regression group (23.4 ± 13.7 months) (p < 0.05). The partial regression group (22%), like the entire regression group, had a higher recurrence rate (5%). The overall proportion of hemangiomas on the face (particularly periocular hemangioma) in the regression group was greater than in the control group.

CONCLUSION

The entire regression group's initial treatment time was significantly shorter than the partial regression group's. As a result, as soon as a hemangioma is discovered, it should be treated. To determine the appropriate time to reduce propranolol, we must evaluate the patient's age and the percentage of tumor regression. Periocular hemangioma may have a better prognosis than other types. Given the small number of patients in our study, we will need to do more research in the future to confirm our findings.

Vascular Malformations: A Histopathologic and Conceptual Appraisal

In the field of vascular anomalies, distinguishing between vascular malformations and tumors has become crucial for a correct therapeutic approach. However, the differential diagnosis between these two groups is not always well explained in classical texts, mainly because many vascular malformations are still known with old names that suggest a tumoral nature. Also, genetic and pathogenic knowledge of these entities has greatly increased in recent decades, so researchers and clinicians now have a better understanding of vascular malformations. In this paper, we present the main histopathological tips to recognize and identify a vascular malformation as such. We also contextualize such information in the clinical and pathogenic knowledge for a better understanding of these entities.

Vascular Malformations: A Histopathologic and Conceptual Appraisal

In the field of vascular anomalies, distinguishing between vascular malformations and tumors has become crucial for a correct therapeutic approach. However, the differential diagnosis between these two groups is not always well explained in classical texts, mainly because many vascular malformations are still known with old names that suggest a tumoral nature. Also, genetic and pathogenic knowledge of these entities has greatly increased in recent decades, so researchers and clinicians now have a better understanding of vascular malformations. In this paper, we present the main histopathological tips to recognize and identify a vascular malformation as such. We also contextualize such information in the clinical and pathogenic knowledge for a better understanding of these entities.

Differential cell composition and split epidermal differentiation in human palm, sole, and hip skin

Palmoplantar skin is structurally and functionally unique, but the transcriptional programs driving this specialization are unclear. Here, we use bulk and single-cell RNA sequencing of human palm, sole, and hip skin to describe the distinguishing characteristics of palmoplantar and non-palmoplantar skin while also uncovering differences between palmar and plantar sites. Our approach reveals an altered immune environment in palmoplantar skin, with downregulation of diverse immunological processes and decreased immune cell populations. Further, we identify specific fibroblast populations that appear to orchestrate key differences in cell-cell communication in palm, sole, and hip. Dedicated keratinocyte analysis highlights major differences in basal cell fraction among the three sites and demonstrates the existence of two spinous keratinocyte populations constituting parallel, site-selective epidermal differentiation trajectories. In summary, this deep characterization of highly adapted palmoplantar skin contributes key insights into the fundamental biology of human skin and provides a valuable data resource for further investigation.

Case report: Transcatheter arterial embolization in a newborn with cervical rapidly involuting congenital hemangioma and Kasabach-Merritt phenomenon

Congenital hemangiomas (CHs) are rare vascular tumors and do not exhibit progressive postnatal growth. The incidence is less than 3% of all hemangiomas. Most CHs have a favorable prognosis; however, the Kasabach-Merritt phenomenon (KMP) is a rare but life-threatening complication in CHs that requires aggressive treatment. Medical treatments with corticosteroids and interferon have been suggested. Surgical resection can be considered for the treatment of complicated CHs in medically resistant lesions. Vascular embolization could be an alternative method if surgery is not considered feasible. Herein, we report a case of a 9-day-old newborn who underwent arterial embolization for a CH with KMP, combined with sirolimus treatment, and the outcome was favorable. The hemangioma completely regressed by 3 months and rapidly involuting congenital hemangioma (RICH) was diagnosed. Our successful experience with treating RICH associated with KMP revealed that RICH can have potentially serious complications although they usually resolve rapidly after birth without treatment. Surgical resection is considered to be the standard method for the treatment of medically resistant vascular tumors, but it is difficult to perform during the active phase of KMP due to acute bleeding and severe coagulopathy. Arterial embolization is feasible and can be used as an alternative to surgical resection, even in small babies.

Multifocal infantile hemangioma of the eyelid causing amblyopia requiring surgical resection

Cutaneous vascular lesions in the pediatric population are rare and may represent a variety of localized and systemic diagnoses with diverse treatment protocols. We present a unique case of an infant with multiple cutaneous vascular lesions, initially diagnosed as congenital disseminated pyogenic granuloma based on histopathologic findings and later diagnosed as multifocal infantile hemangioma with extracutaneous hepatic involvement. The largest vascular lesion in our patient was on the left upper eyelid, which failed medical treatment and ultimately required surgical excision to prevent amblyopia progression.

KIAA1429 promotes infantile hemangioma regression by facilitating the stemness of hemangioma endothelial cells

Infantile hemangiomas are common vascular tumors with a specific natural history. The proliferation and regression mechanism of infantile hemangiomas may be related to the multilineage differentiation ability of hemangioma stem cells, but the specific mechanism is not well elucidated. KIAA1429 is an N⁶ -methyladenosine methylation-related protein that can also exert its role in a methylation-independent manner. This study aims to explore the function of KIAA1429 in infantile hemangiomas. qRT-PCR, western blotting, and immunostaining were performed to verify the expression of KIAA1429. The endothelial and fibroblast-like phenotypes of hemangioma endothelial cells were detected after KIAA1429 knockdown and overexpression. The stemness properties of hemangioma endothelial cells and the underlying mechanism of KIAA1429 in hemangiomas were also investigated. Nude mouse models of infantile hemangiomas were conducted to ascertain the effects of KIAA1429 in vivo. The results showed that KIAA1429 was highly expressed in infantile hemangiomas, particularly in involuting hemangiomas. In vitro experiments confirmed that KIAA1429 inhibited the endothelial phenotype, enhanced the differentiation ability, and promoted the fibroblast-like phenotype of hemangioma endothelial cells by inducing endothelial cell transition to facultative stem cells. However, the effect of KIAA1429 on the potential target was shown to be independent of N⁶ -methyladenosine methylation modification. Mouse models further revealed that KIAA1429 could inhibit the proliferation and promote the regression of hemangiomas. In conclusion, this study found that KIAA1429 played an important role in the regression of infantile hemangiomas by enhancing the stemness of hemangioma endothelial cells and could be a potential treatment target for infantile hemangiomas.

Immunoexpression of proliferation and apoptosis markers in oral vascular anomalies

The biological behavior of lesions is highly dependent on the imbalance between their proliferative and apoptotic capacity. This study evaluated a correlation between the proliferative and apoptotic rates of different oral vascular anomalies (VAs) by analyzing the immunoexpression of proliferation (Ki-67) and apoptosis (Bcl-2 and Bax) markers in endothelial cells of 20 cases of GLUT-1 positive infantile hemangiomas (IHs), 20 cases of pyogenic granulomas (PGs) and 20 cases of vascular malformations (VMs). Immunoexpression analysis of Ki-67, Bcl-2 and Bax revealed a lower median percentage of positive cells in VMs cases compared to IHs and PGs cases (P <0.001). The Wilcoxon signed-rank test showed significantly higher percentages of immunostaining for Bax than for Bcl-2 in IHs (P = 0.048). In the group of PGs, a positive correlation was observed between the immunoexpressions of Ki-67 and Bax (r = 0.476; P = 0.034). Although oral IHs, PGs and VMs present similar clinical and histopathological features, each of these lesions has its etiopathogenic particularities. The results of this study suggest that different biological behaviors of VAs may be related to differences in the proliferative and apoptotic profiles of their endothelial cells.

Numerous Angiomatous Lesions in an Infant

A 3-month-old infant presented with bright red macules, papules, and plaques that appeared at birth and grew in size and number. What is your diagnosis?

Identification of a functional circRNA-miRNA-mRNA regulatory network in infantile hemangioma by bioinformatics analysis

Several circRNA have been reported to serve critical roles in various biological processes of human body. The present study aimed to build a circRNA-based competing endogenous RNA (ceRNA) network and explore the regulatory mechanisms of circRNA in infantile hemangiomas (IH). Differentially expressed circRNA, miRNA, and mRNA were downloaded from the gene expression synthesis (GEO) microarray database (GSE98795, GSE69136, and GSE127487). Cancer-specific circRNA database (CSCD), miRDB and Targetscan were employed to predict the targets of RNA. A total of 855 DEcircRNAs, 69 differentially expressed miRNAs (DEmiRNAs), and 3233 differentially expressed mRNAs (DEmRNAs) appeared as genes that were aberrantly expressed in IH. The circRNA-miRNA-mRNA network was constructed based on 108 circRNAs, 7 miRNAs, 274 mRNAs in IH. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis indicated hypoxia-inducible factors (HIF)-1 signaling pathway and Notch signaling pathway were significantly enriched in IH with being constructed a ceRNA regulatory network. Furthermore, protein-protein interaction (PPI) network and Cytoscape showed the top 10 hub genes that regulate angiogenesis, namely FBXW7, CBLB, HECW2, FBXO32, FBXL7, KLHL5, EP300, MAPK1, MEF2C, and PLCG1. Our findings provide a deeper understanding the circRNA-related ceRNA regulatory mechanism in IH. This study further perfected the circRNA-miRNA-mRNA regulatory network related to IH and explored the potential function of mRNA in this network. It provides more understanding for the circRNA-related ceRNA regulation mechanism in the pathogenesis of IH.

Intraosseous Venous Malformations of the Head and Neck

Intraosseous venous malformations represent a subtype of venous vascular malformations that arise primarily in bone. In the head and neck, intraosseous venous malformations are most frequently found in the skull, skull base, and facial skeleton, with location at the geniculate ganglion of the facial nerve perhaps the most widely recognized. These non-neoplastic lesions are characterized by dilated venous channels with characteristic internal bony spicules on CT but may present with a more complex appearance on MR imaging and may share features with more aggressive lesions. Further confounding the imaging-based diagnosis of intraosseous venous malformation is the frequent misrepresentation of these lesions as hemangiomas in the radiology and clinical literature, as well as in daily practice. Because most intraosseous venous malformations can be left alone, their correct diagnosis may spare a patient unnecessary concern and intervention.

One Molecule for Mental Nourishment and More: Glucose Transporter Type 1—Biology and Deficiency Syndrome

Glucose transporter type 1 (Glut1) is the main transporter involved in the cellular uptake of glucose into many tissues, and is highly expressed in the brain and in erythrocytes. Glut1 deficiency syndrome is caused mainly by mutations of the SLC2A1 gene, impairing passive glucose transport across the blood–brain barrier. All age groups, from infants to adults, may be affected, with age-specific symptoms. In its classic form, the syndrome presents as an early-onset drug-resistant metabolic epileptic encephalopathy with a complex movement disorder and developmental delay. In later-onset forms, complex motor disorder predominates, with dystonia, ataxia, chorea or spasticity, often triggered by fasting. Diagnosis is confirmed by hypoglycorrhachia (below 45 mg/dL) with normal blood glucose, 18F-fluorodeoxyglucose positron emission tomography, and genetic analysis showing pathogenic SLC2A1 variants. There are also ongoing positive studies on erythrocytes’ Glut1 surface expression using flow cytometry. The standard treatment still consists of ketogenic therapies supplying ketones as alternative brain fuel. Anaplerotic substances may provide alternative energy sources. Understanding the complex interactions of Glut1 with other tissues, its signaling function for brain angiogenesis and gliosis, and the complex regulation of glucose transportation, including compensatory mechanisms in different tissues, will hopefully advance therapy. Ongoing research for future interventions is focusing on small molecules to restore Glut1, metabolic stimulation, and SLC2A1 transfer strategies. Newborn screening, early identification and treatment could minimize the neurodevelopmental disease consequences. Furthermore, understanding Glut1 relative deficiency or inhibition in inflammation, neurodegenerative disorders, and viral infections including COVID-19 and other settings could provide clues for future therapeutic approaches.

Is Infantile Hemangioma a Neuroendocrine Tumor?

Infantile hemangioma (IH) is the most common infantile tumor, affecting 5–10% of newborns. Propranolol, a nonselective β-adrenergic receptor (ADRB) antagonist, is currently the first-line treatment for severe IH; however, both its mechanism of action and its main cellular target remain poorly understood. Since betablockers can antagonize the effect of natural ADRB agonists, we postulated that the catecholamine produced in situ in IH may have a role in the propranolol response. By quantifying catecholamines in the IH tissues, we found a higher amount of noradrenaline (NA) in untreated proliferative IHs than in involuted IHs or propranolol-treated IHs. We further found that the first three enzymes of the catecholamine biosynthesis pathway are expressed by IH cells and that their levels are reduced in propranolol-treated tumors. To study the role of NA in the pathophysiology of IH and its response to propranolol, we performed an in vitro angiogenesis assay in which IH-derived endothelial cells, pericytes and/or telocytes were incorporated. The results showed that the total tube formation is sensitive to propranolol only when exogenous NA is added in the three-cell model. We conclude that the IH’s sensitivity to propranolol depends on crosstalk between the endothelial cells, pericytes and telocytes in the context of a high local amount of local NA.

The role of hypoxia in the pathogenesis of congenital hyperplasia of blood vessels in the head and neck in children (literature review)

To date, scientists have found that stress plays an important role in the formation of congenital malformations. It can be caused by the influence of negative environmental factors on the pregnant woman or by her own diseases. One of the consequences of stress is hypoxia. It can be acute and chronic, and can have a negative impact both during pregnancy and during childbirth. They also distinguish local and general hypoxia. The consequences of the negative impact of oxygen deficiency on the embryo and fetus can manifest itself both in utero and after birth, leading to  various kinds of congenital malformations, diseases, and sometimes fetal death, or increase the risk of sudden infant death syndrome. Hyperplasia of blood vessels, the so-called children’s hemangiomas, develops both in utero, especially with chronic fetal hypoxia, and during childbirth. It develops due to insufficient blood supply and oxygen deficiency in various parts of the body, most often in the head and neck. In an embryo under conditions of hypoxia, tachycardia develops – with an increase in heart rate and, if it is ineffective, local vasodilation occurs. Only then, under the condition of continuing hypoxia, does an increase in the number of blood vessels develop. This often leads to the formation of hyperplasia of the blood vessels, the so-called children’s hemangiomas.

This pathology is quite common, especially among fair-skinned children, which makes its study, in particular the factors that cause this pathology, relevant today. 

KRIT1-positive hyperkeratotic cutaneous capillary venous malformation

Cerebral cavernous malformations (CCM) may present in sporadic or familial forms, with different cutaneous manifestations including deep blue nodules, capillary malformations, and hyperkeratotic cutaneous capillary venous malformations (HCCVM). We report the case of an infant with a KRIT1-positive HCCVM associated with familial CCM. Moreover, histopathology showed positive immunohistochemical stain with GLUT1, further expanding the differential diagnosis of GLUT1-positive vascular anomalies.

Vascular anomalies: clinical perspectives

Vascular anomalies are classified as vascular tumors or vascular malformations according to their cellular features and biological behavior. Detailed history and clinical assessment allow for the proper clinical diagnosis of most vascular anomalies and guide the choice of imaging to evaluate them. This article discusses the general information needed from a clinical history and physical exam to formulate a diagnosis of vascular anomaly. Then, the authors review the clinical findings from the most common vascular tumors and vascular malformations.

Infantile hemangiomas β3-adrenoceptor overexpression is associated with nonresponse to propranolol

BACKGROUND

Propranolol (antagonist of β₁-/β₂-AR but minimally active against β₃-AR) is currently the first-line treatment for infantile hemangiomas (IH). Its efficacy is attributed to the blockade of β₂-AR. However, its success rate is ~60%. Considering the growing interest in the angiogenic role of β₃-ARs, we evaluated a possible relationship between β₃-AR expression and response to propranolol.

METHODS

Fifteen samples of surgical biopsies were collected from patients with IH. Three were taken precociously from infants and then successfully treated with propranolol (responder group). Twelve were taken later, from residual lesions noncompletely responsive to propranolol (nonresponder group). A morphometrical analysis of the percentage of β₁-, β₂-, and β₃-ARs positively stained area was compared between the two groups.

RESULTS

While no difference was found in both β₁- and β₂-AR expression level, a statistically significant increase of β₃-AR positively stained area was observed in the nonresponder group.

CONCLUSIONS

Although the number of biopsies is insufficient to draw definitive conclusions, and the different β-AR pattern may be theoretically explained by the different timing of samplings, this study suggests a possible correlation between β₃-AR expression and the reduced responsiveness to propranolol treatment. This study could pave the way for new therapeutic perspectives to manage IH.

IMPACT

Propranolol (unselective antagonist of β₁ and β₂-ARs) is currently the first-line treatment for IHs, with a success rate of ~60%. Its effectiveness has been attributed to its ability to block β₂-ARs. However, β₃-ARs (on which propranolol is minimally active) were significantly more expressed in hemangioma biopsies taken from patients nonresponsive to propranolol. This study suggests a possible role of β₃-ARs in hemangioma pathogenesis and a possible new therapeutic target.

Is primary hepatic angiosarcoma in children an indication for liver transplantation?-A single-centre experience and review of the literature

PHA in the paediatric population is an extremely rare and aggressive malignant soft tissue neoplasm, with less than 50 cases published worldwide. The prognosis is dismal. If the tumour is unresectable, one treatment option is LT. In this article, the current available literature is reviewed and additionally, three cases of paediatric patients with PHA who underwent LT at Karolinska University Hospital, Sweden, are presented. Based on the literature and our own experience, there is undoubtedly possible good outcome of LT due to PHA. On the contrary, no patients have survived PHA without LT. PHA in paediatric patients should be recommended to LT in selected patients. Effect of modern adjuvant chemo and RT should be evaluated further based on international registry for such rare cases of PHA.

Isolated Focal Infantile Hemangioma of the Alveolar Ridge with Glucose Transporter-1 Reactivity: An Aberrant Presentation

Aim and objective

To give dental practitioners an insight into the unusual presentation of focal infantile hemangioma on the alveolar ridge showing immunoreactivity to glucose transporter-1 (GLT1). We also recommend the importance of using standardized terminologies to describe the type of hemangioma.

Background

One of the most commonly seen and misdiagnosed vascular tumors of the skin and soft tissues of the head and neck region in children are infantile hemangiomas. Infantile hemangiomas developing at extracutaneous locations such as the oral cavity are rare, especially without cutaneous involvement.

Case description

A 9-month-old infant girl presented to the Pediatric Dental Department with a swelling over the maxillary alveolar ridge. The solitary exophytic mass appeared after birth and gradually enlarged in size with episodes of bleeding during feeding. Clinical examination revealed a reddish-pink pedunculated mass that bled profusely on palpation. The lesion was excised by electrocautery and was found to be express glucose transporter-1 confirming the diagnosis of infantile hemangioma. The patient was followed up for 1 year and showed no recurrence.

Conclusion

Hemangiomas are usually misinterpreted to be pyogenic granulomas, vascular malformation, reactive granulation tissue, or congenital granular cell tumor. This report highlights the use of glucose transporter-1 when there is suspicion of hemangioma for immunohistochemical distinction from other histologically similar vascular lesions of the oral cavity.

Clinical significance

Dental surgeons treating vascular lesions of the oral cavity should advocate for surgical management techniques that also produce hemostasis due to the risk of intraoperative bleeding.

How to cite this article

Natarajan D, Muthukali S, Nachiappan N, et al. Isolated Focal Infantile Hemangioma of the Alveolar Ridge with Glucose Transporter-1 Reactivity: An Aberrant Presentation. Int J Clin Pediatr Dent 2021;14(2):319–322.

Re-analysis of whole-exome sequencing data reveals a novel splicing variant in the SLC2A1 in a patient with GLUT1 Deficiency Syndrome 1 accompanied by hemangioma: a case report

Background

GLUT1 Deficiency Syndrome 1 (GLUT1DS1) is a neurological disorder caused by either heterozygous or homozygous mutations in the Solute Carrier Family 2, Member 1 (SLC2A1) gene. SLC2A1 encodes Glucose transporter type 1 (GLUT1) protein, which is the primary glucose transporter at the blood–brain barrier. A ketogenic diet (KD) provides an alternative fuel for brain metabolism to treat impaired glucose transport. By reanalyzing exome data, we identified a de novo heterozygous SLC2A1 variant in a girl with epilepsy. After reversed phenotyping with neurometabolic tests, she was diagnosed with GLUT1DS1 and started on a KD. The patient's symptoms responded to the diet. Here, we report a patient with GLUT1DS1 with a novel SLC2A1 mutation. She also has a hemangioma which has not been reported in association with this syndrome before.

Case presentation

A 5-year 8-month girl with global developmental delay, spasticity, intellectual disability, dysarthric speech, abnormal eye movements, and hemangioma. The electroencephalography (EEG) result revealed that she had epilepsy. Magnetic resonance imaging (MRI) showed that non-specific white matter abnormalities. Whole Exome Sequencing (WES) was previously performed, but the case remained unsolved. The re-analysis of WES data revealed a heterozygous splicing variant in the SLC2A1 gene. Segregation analysis with parental DNA samples indicated that the variant occurred de novo. Lumbar puncture (LP) confirmed the diagnosis, and the patient started on a KD. Her seizures responded to the KD. She has been seizure-free since shortly after the initiation of the diet. She also had decreased involuntary movements, her speech became more understandable, and her vocabulary increased after the diet.

Conclusions

We identified a novel de novo variant in the SLC2A1 gene in a patient who previously had a negative WES result. The patient has been diagnosed with GLUT1DS1. The syndrome is a treatable condition, but the differential diagnosis is not an easy process due to showing a wide range of phenotypic spectrum and the overlapping symptoms with other neurological diseases. The diagnosis necessitates a genomic testing approach. Our findings also highlight the importance of re-analysis to undiagnosed cases after initial WES to reveal disease-causing variants.

Effect of Oral Propranolol on Periocular Infantile Capillary Hemangioma: Outcomes Based on Extent of Involvement

PURPOSE

To evaluate the efficacy of oral propranolol in the treatment of periocular infantile capillary hemangioma (CHI) based on the involvement of embryological facial placodes and their extent of anatomical involvement.

METHODS

Retrospective study of 27 patients.

RESULTS

The mean age at the presentation of periocular CHI was 4 months (median, 3 months; range, <1-14 months). There were 11 (41%) males and 16 (59%) females. Based on embryological facial placodes, the involvement was focal in 16 (59%) cases and segmental in 11 (41%) cases. Based on the anatomical distribution, the lesions were preseptal in 4 (15%), postseptal in 13 (48%), and combined in 10 (37%) cases. The duration of use of oral propranolol was 10 months (median, 10 months; range, 4-16 months). Overall, the mean % resolution of periocular CHI was 78% (median, 90%; range, 20%-100%). The mean percentage resolution of focal lesions was 69% (median, 83%; range, 20%-100%), and segmental lesions were 92% (median, 95%; range, 70%-100%). The mean percentage resolution of preseptal component of lesions was 94% (median, 95%; range, 80%-100%) and postseptal component was 74% (median, 85%; range, 20%-100%) over a mean follow-up period of 16 months (median, 15 months; range, 4-37 months). Four (15%) patients exhibited flare-up of lesion after tapering oral propranolol.

CONCLUSION

Oral propranolol is effective in the treatment of periocular CHI. Segmental and preseptal lesions respond better to the treatment compared to focal and postseptal lesions.

Critical role of Aquaporin-1 and telocytes in infantile hemangioma response to propranolol beta blockade

Propranolol, a nonselective β-adrenergic receptor (ADRB) antagonist, is the first-line therapy for severe infantile hemangiomas (IH). Since the incidental discovery of propranolol efficacy in IH, preclinical and clinical investigations have shown evidence of adjuvant propranolol response in some malignant tumors. However, the mechanism for propranolol antitumor effect is still largely unknown, owing to the absence of a tumor model responsive to propranolol at nontoxic concentrations. Immunodeficient mice engrafted with different human tumor cell lines were treated with anti-VEGF bevacizumab to create a model sensitive to propranolol. Proteomics analysis was used to reveal propranolol-mediated protein alteration correlating with tumor growth inhibition, and Aquaporin-1 (AQP1), a water channel modulated in tumor cell migration and invasion, was identified. IH tissues and cells were then functionally investigated. Our functional protein association networks analysis and knockdown of ADRB2 and AQP1 indicated that propranolol treatment and AQP1 down-regulation trigger the same pathway, suggesting that AQP1 is a major driver of beta-blocker antitumor response. Examining AQP1 in human hemangioma samples, we found it exclusively in a perivascular layer, so far unrecognized in IH, made of telocytes (TCs). Functional in vitro studies showed that AQP1-positive TCs play a critical role in IH response to propranolol and that modulation of AQP1 in IH-TC by propranolol or shAQP1 decreases capillary-like tube formation in a Matrigel-based angiogenesis assay. We conclude that IH sensitivity to propranolol may rely, at least in part, on a cross talk between lesional vascular cells and stromal TCs.

Glut 1, S-100, and Nerve Bundle Study in Vascular Anomalies

Vascular anomalies grouped into vascular tumors (hemangioma) (HI) and vascular malformation (VM) are benign vascular lesions that are difficult to distinguish from one another clinically and often confused with each other at histopathology. This confusing terminology leads to improper diagnosis, illogical treatment, and misdirected research. This study aimed to study GLUT 1, S-100, and nerve bundle to differentiate hemangioma and vascular malformation. Thirty two cases of vascular lesions (26 vascular malformations and 6 hemangiomas) were taken into the study. For histological evaluation and immunohistochemistry (IHC), samples of vascular lesions were collected in formalin. All the hematoxylin and eosin-stained slides were evaluated under light microscope for histology and nerve bundles. Immunohistochemical staining was performed by streptavidin–biotin method for GLUT 1 and S-100. GLUT 1 was positive in all 6 cases of hemangiomas (100%) and only in 1 case of vascular malformation. Nerve bundle was present in 24 cases of vascular malformation (92.3%) out of 26 cases but not in any cases of hemangioma and S-100 was found positive in all vascular malformation cases (100%) but not in hemangioma. So GLUT 1 expression, S-100, and presence of nerve bundle in vascular lesions can help to differentiate hemangioma and vascular malformation.

Primary malignant vascular tumors of the liver in children: Angiosarcoma and epithelioid hemangioendothelioma

Primary malignant vascular neoplasms of the liver, angiosarcoma and epithelioid hemangioendothelioma, are extremely rare entities in the pediatric population. International Society for the Study of Vascular Anomalies classification system is recommended for the pathologic diagnosis of hepatic vascular lesions in this age group. In this article, we highlight the clinicopathologic characteristics of hepatic angiosarcoma and epithelioid hemangioendothelioma in the pediatric population. Hepatic angiosarcoma in children shows a slight female predominance with an average age of 40 mo at diagnosis. The distinct histologic features include whorls of atypical spindled cells and eosinophilic globules, in addition to the general findings of angiosarcoma. Histologic diagnosis of pediatric hepatic angiosarcoma is not always straightforward, and the diagnostic challenges are discussed in the article. Hepatic epithelioid hemangioendothelioma also demonstrates a female predominance, but is more commonly identified in adolescents (median age at diagnosis: 12 years). Histologically, the lesion is characterized by epithelioid cells and occasional intracytoplasmic lumina with a background of fibromyxoid stroma. While WWTR1-CAMTA1 and YAP1-TFE3 fusions have been associated with epithelioid hemangioendothelioma, there are currently no known signature genetic alterations seen in pediatric hepatic angiosarcoma. Advancement in molecular pathology, particularly for pediatric hepatic angiosarcoma, is necessary for a better understanding of the disease biology, diagnosis, and development of targeted therapies.

Evaluation of GLUT1, IGF-2, VEGF, FGF 1, and angiopoietin 2 in infantile hemangioma

INTRODUCTION

Infantile hemangioma (IH) is a common vascular tumor in children. It is reported that IHs are associated with immunochemical markers such as vascular endothelial growth factor (VEGF)-A, glucose transporter isoform 1 (GLUT1), and insulin-like growth factor-2 (IGF-2).

MATERIAL AND METHODS

This cross-sectional study focused on pediatric patients with IH. A total of 46 patients (mean age 14.2±21.9 months) with IH and 45 healthy controls (mean age 21.8±15.08 months) were enrolled. Demographic data, clinical findings, and laboratory parameters were recorded. Blood samples were collected. Serum GLUT1, IGF-2, VEGF-A, fibroblast growth factor 1 (FGF1), and angiopoietin 2 levels were assessed by enzyme-linked immunosorbent assay.

RESULTS

Serum GLUT1, IGF-2, and VEGF-A levels were significantly higher in patients with IH than in healthy controls (8.80±4.07pg/mL vs. 5.66±4.34pg/mL, 281.10±84.12pg/mL vs. 234.19±75.38pg/mL, 1196.99±389.34pg/mL vs. 996.99±349.16pg/mL, respectively, p=0.026, p=0.030, and p=0.036). Serum GLUT1, IGF-2, and VEGF-A levels in patients with complicated hemangioma were significantly higher than in healthy controls (9.69±3.94pg/mL vs. 5.66±4.34pg/mL, 289.94±83.18pg/mL vs. 234.19±75.38pg/mL, 1276.22±388.24pg/mL vs. 996.99±349.16pg/mL, respectively, p=0.017, p=0.022, and p=0.011). Serum GLUT1, IGF-2, and VEGF-A levels in patients with hemangioma receiving propranolol treatment were significantly higher than in healthy controls. Serum FGF1 levels were higher in patients with IH, complicated hemangioma, and hemangioma receiving propranolol treatment than in healthy controls but the difference was not statistically significantly.

CONCLUSION

Serum GLUT1, IGF-2, and VEGF-A levels were positively correlated with disease severity in patients with hemangioma, for example, in complicated hemangioma and hemangioma requiring propranolol treatment. However, further research on larger and different age subgroups is warranted to assess these markers.

Vascular Anomalies of the Head and Neck: A Pediatric Overview

Vascular anomalies, further classified into vascular tumors and malformations, often involve the head and neck region of children. These entities may raise diagnostic dilemmas, as they often demonstrate heterogenous and overlapping histologic features. The aim of this paper is to provide an overview of the common vascular anomalies in the head and neck region of children. Specific entities discussed include infantile hemangioma, congenital hemangioma, tufted angioma, kaposiform hemangioendothelioma, and various vascular malformations. Clinicopathologic features and associated molecular associations are reviewed.