Intestinal obstruction due to kaposiform hemangioendothelioma in a 1-month-old infant: A case report

MEK inhibition reduced vascular tumor growth and coagulopathy in a mouse model with hyperactive GNAQ

Activating non-inherited mutations in the guanine nucleotide-binding protein G(q) subunit alpha (GNAQ) gene family have been identified in childhood vascular tumors. Patients experience extensive disfigurement, chronic pain and severe complications including a potentially lethal coagulopathy termed Kasabach-Merritt phenomenon. Animal models for this class of vascular tumors do not exist. This has severely hindered the discovery of the molecular consequences of GNAQ mutations in the vasculature and, in turn, the preclinical development of effective targeted therapies. Here we report a mouse model expressing hyperactive mutant GNAQ in endothelial cells. Mutant mice develop vascular and coagulopathy phenotypes similar to those seen in patients. Mechanistically, by transcriptomic analysis we demonstrate increased mitogen activated protein kinase signaling in the mutant endothelial cells. Targeting of this pathway with Trametinib suppresses the tumor growth by reducing vascular cell proliferation and permeability. Trametinib also prevents the development of coagulopathy and improves mouse survival.

18F-FDG PET/CT Findings in a Woman With Kaposiform Hemangioendothelioma in the Sacrum

ABSTRACT

Kaposiform hemangioendothelioma is a rare vascular tumor with borderline malignancy and is typically diagnosed in infancy or early childhood. It most commonly affects cutaneous tissues, whereas the subtype with only primary bone involvement is extremely rare. Herein, we report a case of Kaposiform hemangioendothelioma involving the sacrum in a 37-year-old woman, with intense 18F-FDG accumulation in the lytic lesion on PET/CT. This case indicates that Kaposiform hemangioendothelioma with the primary bone involvement should be taken into consideration as a rare differential diagnosis for lytic lesions with increased 18F-FDG uptake on PET/CT.

Neonatal Intestinal Obstruction Due to Kaposiform Hemangioendothelioma of the Jejunum

Kaposiform hemangioendothelioma is a borderline vascular tumor usually seen in infants and children as cutaneous lesions classically associated with the Kasabach-Merritt phenomenon. Intestinal involvement is uncommon and can cause acute presentations, such as obstruction or gastrointestinal bleeding. A 5-day-old neonate presented with bilious vomiting for 2 days. The tumor was in the jejunum. Histopathological examination with immunohistochemistry of the resected jejunum showed CD34 positive endothelial lined vascular spaces infiltrating from submucosa to serosa, which is classical of kaposiform hemangioendothelioma. There was no deranged coagulation profile. This case forms an interesting cause for neonatal intestinal obstruction.

Kaposiform hemangioma of jejunum in a newborn: A case report and review of literature

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Kaposiform hemangioma is a rare tumor, of vascular origin, usually in childhood.

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The diagnosis sometimes is made only in the intraoperative.

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It is possible to make a differential diagnosis with congenital intestinal stenosis.

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Surgery is consisted of resection of the stenotic area.

Introduction

Kaposiform hemangioendothelioma is a rare tumor, of vascular origin, which predominates in childhood. Although it is frequently a vascular cutaneous anomaly, it is known that some cases can involve bones, mediastinum and retroperitoneum, being even rarer when it occurs in the small intestine, representing only 0.05% of all intestinal neoplasms.

Presentation of case

Female patient, 21 days old, born at 38 weeks, is admitted to the hospital due to bilious vomiting, dehydration and major abdominal distension. An X-ray of the acute abdomen suggests type I jejunal atresia. An exploratory laparotomy was performed, with the presence of a stenotic area in the proximal jejunum, which was chosen for resection of the stenotic area and end-to-end terminal anastomosis, with post-pyloric jejunostomy. The presence of kaposiform hemangioma was confirmed by immunohistochemistry, and the patient had no further complications.

Discussion

The presence of hemangiomas in childhood is frequent, is but it very rare when it appears in the gastrointestinal location, as reported in the present case. A common presentation is intestinal bleeding, being manifested as anemia or, sometimes, acute and potentially fatal anemia. Other forms of rare presentation include intussusception, perforation and obstruction, the latter being out patient's last manifestation. The diagnosis of this alteration can be difficult, and often performed only in the intraoperative period of an exploratory laparotomy.

Conclusion

The presence of bilateral vomiting and intestinal obstruction in newborns opens the possibility of a wide range of possible diagnoses, such as the presence of intestinal atresia. Kaposiform intestinal hemangioma is an uncommon cause in these clinical manifestations, but it should be included in the differential diagnosis.

Successful Management of Kaposiform Hemangioendothelioma with Long-Term Sirolimus Treatment: a Case Report and Review of the Literature

Background

Kaposiform Hemangioendothelioma (KHE) is a rare vascular tumour of the infancy and the first decade of life. It is locally aggressive and potentially life threatening when associated with consumptive coagulopathy, known as Kasabach-Merritt syndrome (KMS). No consensus or guideline for the therapy has been reached because of the lack of prospective trials, and the different standard care suggestions are based on retrospective case series.

Case report

We report the case of a 9-month-old male with KHE and KMS in which the initial response, obtained with prednisone and vincristine, was subsequently consolidated and strengthened by long-term treatment with sirolimus, a mTOR inhibitor. A summary of the published data is presented as well.

Conclusions

The inhibition of mTOR pathway represents the most important therapeutic innovation introduced in the last few years for KHE. Our case shows the effectiveness and good tolerance of long-term therapy with sirolimus.