Successful treatment of Kasabach-Merritt syndrome with transarterial embolization and corticosteroids

Efficacy of transcatheter arterial chemoembolization combined with sirolimus for treating Kasabach-Merritt phenomenon in infants, a retrospective study

OBJECTIVE

This retrospective study aimed to observe the efficacy of transcatheter arterial chemoembolization (TACE) combined with sirolimus in the treatment of haemangioma combined with the Kasabach-Merritt phenomenon (KMP).

METHODS

A total of 11 infants with KMP who were treated at our hospital from January 2016 to September 2021 were selected and treated with arteriosclerosis embolotherapy using a microsphere emulsion formed by bleomycin + ultra-fluid lipiodol + dexamethasone + contrast agent or bleomycin mixed microspheres as the embolising agent. The patients were administered sirolimus orally after TACE. The clinical efficacy and examination indicators before and after treatment were observed and compared.

RESULTS

The 11 infants underwent TACE treatment by arteriosclerosis embolotherapy a total of 21 times; of these cases, 10 were cured, and 1 showed a moderate response. There were no cases of non-response or death. The platelet count rose from 10.0 (7.0, 18.0) x 10⁹/L before TACE to 236.0 (188.0, 275.0) x 10⁹/L six months after the first TACE, and the tumour size decreased from 49.0 (43.0, 111.7) cm³ before TACE to 7.0 (3.5, 17.0) cm³ six months after the first TACE. The differences were statistically significant (the Z values were -2.943 and -2.934, respectively, p < 0.05).

CONCLUSION

The combination of TACE and sirolimus has significant efficacy on critical children with KMP.

Case Report: Congenital Intracranial Kaposiform Hemangioendothelioma Treated With Surgical Resection

Background

Kaposiform hemangioendothelioma (KHE) is a locally aggressive but non-metastatic vascular neoplasm. Most studies have been restricted to small case series of limited generalizability. Intracranial KHE is extremely rare with only three cases reported in the literature. Here, we report a case of congenital intracranial KHE who underwent surgical resection, and no lesion recurrence was seen during the follow-up period of 13 months.

Case Description

A 2-month-old boy initially presented with a left temporal mass following birth. Antenatal ultrasound at 36 weeks of gestation demonstrated a hyperechoic signal present in the left frontal lobe, with clear borders and irregular morphology. There were neither cutaneous abnormalities nor other neurologic examination abnormalities. No laboratory abnormality was identified. Computed tomography (CT) scans suggested that a massive hematoma was noted under the left frontal skull plate, with a little subdural hemorrhage in the adjacent temporal area. The adjacent meninges enhanced and thickened on contrasted T1 magnetic resonance (MR). After the multidisciplinary diagnostic assessment, the surgery was performed by the left frontotemporal craniotomy approach. The operation was extremely difficult. We completely removed the tumor, and the involved dura and brain tissue were resected with the lesion in a piecemeal fashion. On postoperative-day (POD) 3 and POD 14, the head CT re-examination revealed that cerebral perfusion improved gradually. The MRI of 6- and 12-month after operation showed no local recurrence or metastasis.

Conclusions

Intracranial KHE is difficult to diagnose early and the prognosis has been uniformly poor. We supposed that meticulous intraoperative hemostasis is the key for a successful operation, and the radical resection of the tumor and involved structures are essential to reduce recurrence.

Effective low dose sirolimus regimen for kaposiform hemangioendothelioma with Kasabach-Merrit Phenomenon in young infants

AIM

Management of kaposiform hemangioendotheliomas (KHE) with Kasabach-Merrit phenomenon is challenging in young infants who are subjected to developmental pharmacokinetic changes. Sirolimus, sometimes combined with corticosteroids, can be used as an effective treatment of KHE. Simultaneously, toxicities like interstitial pneumonitis related to the use of sirolimus may be fatal. As infants have a very low CYP3-enzyme expression at birth, which rises during ageing, we hypothesize, that a reduced metabolization of sirolimus might lead to high sirolimus serum levels and low dose may be sufficient without the side effects.

METHODS

A case series of five infants with kaposiform hemangioendothelioma with Kasabach-Merrit phenomenon was analysed retrospectively. All infants were treated with sirolimus - 0.2 mg/m2 every 24 or 48 hours according to their age. Prednisone was added to the therapy for additional effect in four patients.

RESULTS

In all patients low dose of sirolimus led to therapeutic sirolimus levels (4-6 ng/mL). All infants (aged 4 days - 7 months) had a complete haematological response, without serious adverse events. In all patients, the Kasabach-Merrit phenomenon resolved, the coagulation profile normalized and tumour size reduction was seen.

CONCLUSION

Low dose sirolimus treatment is safe for infants with kaposiform hemangioendothelioma and Kasabach-Merit phenomenon. Essential is to realize that during the first months of life, metabolism is still developing and enzymes necessary to metabolise drugs like sirolimus still have to mature. To avoid toxic levels, the sirolimus dosage should be based on age and the associated pharmacological developments.

Analysis of angiographic characteristics of kaposiform hemangioendothelioma and investigation of the value of transcatheter arterial embolization therapy

BACKGROUND

This study aimed to analyze the angiographic characteristics of kaposiform hemangioendothelioma (KHE) and investigate the value of transcatheter arterial embolization (TAE) therapy.

METHODS

The clinical data of infants diagnosed with KHE at the department from June 2013 to June 2020 were retrospectively analyzed. Of these, 34 infants received TAE therapy. The efficacy of the treatment was evaluated 4 weeks after the therapy. The angiographic characteristics were analyzed by comparing them with the angiographic characteristics of infantile hemangioma (IH), and the times of TAE therapy and the platelet level after each TAE therapy in infants with KHE were summarized.

RESULTS

The present study showed that the capillary blush of KHE was irregular with an obscure boundary and nonuniform distribution. Many fine feeding arteries were present. The diameter of the feeding arteries was disproportionate to the volume of the tumor blush. The normal arteries were usually embedded in the tumor blush. The angiography of common IH in infants also showed tumor blush, but it was usually round with a clear boundary and uniform staining, and was distributed on 1 side of the normal arterial trunk. The infants with KHE received TAE therapy for 2 to 5 times/case, with a total of 104.0 times, with an average of 3.1±0.8/case. Among which, the platelets continued to decline for 9 times after TAE therapy and the platelets increased to ≥100×10⁹/L in 7.8±3.2 days for 95 times after TAE therapy, The average relapse time was 30.0±15.9 days.

CONCLUSIONS

The feeding arteries of KHE were numerous and fine and were not easily embolized. The application of TAE may rapidly improve the platelet level, but the long-term effect is poor.

Neonatal Vascular Tumors

Vascular tumors are a part of the vascular anomalies spectrum. Vascular malformations are congenital vascular lesions, originating from a mesenchymal stem cell defect and distinguished from vascular tumors by their low cell turnover and lack of invasiveness. They tend to grow in proportion to the child. Vascular tumors are proliferative and range from benign proliferation to malignant tumors. The appropriate differential diagnosis is imperative. Infantile hemangioma can be diagnosed clinically and rarely requires therapy; more rare tumors are difficult to diagnose and treat. This review provides an overview of vascular tumors seen in the neonatal period and summarizes treatment options.

Effective surgical treatment of life-threatening huge vascular anomalies associated with thrombocytopenia and coagulopathy in infants unresponsive to drug therapy

BACKGROUND

Systemic drug therapy is generally recommended for infant huge vascular anomalies associated with thrombocytopenia and coagulopathy, but some patients are not suitable due to drug unresponsiveness or life threatening conditions before the drug works, who will need to receive surgical treatment. This study retrospectively analyzed the clinical features, imaging features, and surgical outcomes of these patients.

METHODS

The clinical data of 4 infants with huge vascular anomalies (2 vein malformations (VMs) and 2 kaposiform hemangioendothelioma (KHE)) associated with thrombocytopenia and coagulopathy treated from June 2016 to December 2017 were retrospectively analyzed. All patients received glucocorticoids, propranolol, vincristine or sirolimus treatment before admission, but the treatment was ineffective. Skin petechia, thrombocytopenia and coagulopathy were present at the time of admission. CT scanning was performed before operation. The patient's general clinical data, hematological examination results, operation time, surgical bleeding volume, blood transfusion volume and surgical complications were collected for analysis. The patients were followed up for 10-26 months.

RESULTS

CT scanning results of 2 patients showed special CT features without detectable enhancement within the lesion after CT enhanced scanning and multiple phleboliths formation. Four patients underwent surgical treatment successfully. Two patients underwent complete resection of the lesion, and 2 underwent cytoreductive surgery. Preoperative clinical symptoms such as skin petechia, thrombocytopenia and coagulopathy were normal at 1 week after surgery. Postoperative pathological results showed 2 cases of KHE and 2 cases of VMs. All patients were discharged from hospital without physical dysfunction, recurrence, or death.

CONCLUSIONS

Timely and appropriate surgical intervention can achieve satisfactory results for infants with huge VMs and KHE who were unresponsive to drug therapy or suffering from life-threatening occasion before the drug become effective.

Abnormal hemostasis in children with vascular anomalies, part I: Thrombocytopenias among different vascular anomalies

Long before the classification of vascular anomalies from the International Society for the Study of Vascular Anomalies (ISSVA) provided a framework to differentiate vascular anomalies, otherwise known as vascular birthmarks, it was recognized that patients with such lesions can present with acute life-threatening hemostatic and/or thrombotic complications, as well as chronic long-standing bleeding or thrombotic issues. Scenarios such as a rapidly growing vascular lesion with severe acute thrombocytopenia, a visceral hemorrhagic lesion, a lesion associated with repetitive and painful superficial thrombosis, and cases of unprovoked or post-procedural fatal pulmonary embolism highlight the wide spectrum of manifestations of abnormal coagulation in patients with vascular anomalies. The separation of vascular anomalies into two distinct groups, vascular tumors and vascular malformations, was followed by the characterization that their respective coagulopathies were due to either a derangement of platelets or to a disequilibrium of the patient's coagulation/fibrinolytic process. This configuration of coagulopathies will be the foundation for this two-chapter review series. In the initial review, coagulopathies where thrombocytopenia is the main feature will be characterized, whereas the second review will focus on vascular malformations that have a coagulation disorder secondary to some degree of coagulation consumption and/or fibrinolytic pathway derangement.

Successful management of steroid-resistant vascular tumors associated with the Kasabach-Merritt phenomenon using sirolimus

Vascular tumors associated with Kasabach-Merritt phenomenon (KMP) are life-threatening and the mortality is as high as 10-30%. Steroids are considered the primary choice for drug therapy. However, there are many steroid-resistant cases. In the present study, analyzed data are presented to support the use of sirolimus in clinical practise for the treatment of corticosteroid-resistant vascular tumors with KMP in eight infants between June 2015 and April 2017 in a single hospital. The time to initial response was 6.8 ± 2.7 days. The average stabilization time for the platelet count was 19.1 ± 8.5 days. At the time of publication, the average duration of sirolimus treatment was 14.1 ± 4.0 months, and the average time for sirolimus treatment as a single agent was 12.6 ± 4.2 months. The side-effects were tolerable and included oral ulcer, fever, pain, skin rash and transient ascension of serum transaminase and cholesterol. Our study indicated that sirolimus therapy is an effective and safe method for the treatment of corticosteroid resistant vascular tumors associated with KMP in infants.

Vascular anomaly cases for the pediatric hematologist oncologists-An interdisciplinary review

Vascular anomalies (VAs) are classified as tumors or malformations depending on their clinical characteristics, pathological diagnosis, and genomic information. Diagnosis can be challenging because of the heterogeneity of clinical presentation; thus, the best diagnosis and care are provided by an interdisciplinary team of specialists. Over the past 10 years, an increasing number of pediatric hematologist/oncologists are caring for patients with VAs secondary to new medical therapy options and clinical trials. This paper focuses on complicated VA issues often seen by the pediatric hematologist/oncologist. The paper reviews clinical pearls on diagnosis, histology, radiology, and treatment options.