Sirolimus for Kaposiform Hemangioendothelioma and Kasabach-Merritt Phenomenon in a Neonate

Sirolimus for vascular anomalies in the first year of life: a systematic review

Evidence on effectiveness and safety of sirolimus in congenital vascular anomalies in infancy is lacking. We aim to systematically review the efficacy and safety of sirolimus in treating congenital VA in infancy. We searched for and included all studies evaluating sirolimus for VA in the first year of life. The primary outcome was effectiveness. The secondary outcome was safety. We included 84 case series and reports (172 participants). Sirolimus decreased the size of the VA in >50% of participants, most of whom had minor transient side effects, and 27% had no adverse effects at all. When categorized by age (<1 month, 1-5 months and 6-12 months), the effectiveness was similar in all age groups. Available evidence suggests that sirolimus is effective and well tolerated. The effectiveness of sirolimus should be evaluated in a well-designed randomized controlled or observational studies.

Euphorbia helioscopia L. exhibits promising therapeutic effects on hemangioendothelioma and melanoma through angiogenesis inhibition

BACKGROUND

Euphorbia helioscopia L (EHL), a widely used medicinal plant in traditional Chinese medicine, has shown promising effects on certain cancers. However, previous studies on EHL did not elucidate the underlying molecular mechanisms. Herein, for the first time, we present the strong therapeutic potential of EHL extracts on malignant hemangioendothelioma, a rare type of vascular tumor.

PURPOSE

To investigate the potential anti-tumor mechanism of extracts of EHL on hemangioendothelioma and melanoma.

METHODS

The dried stems and leaves of EHL were extracted with Ethyl Acetate and n-Butyl alcohol, yielding two crude extracts Ethyl Acetate fraction (EA) and n-Butyl alcohol fraction (Bu). EA and Bu were prepared to assess the potential mechanism by assays for cell proliferation, cell cycle, apoptosis, colony formation, tube formation, cellular metabolic activity, reactive oxygen species (ROS), N-Acetylcysteine (NAC) antagonism, RNA expression and western blot. To further confirm the anti-tumor effect of EHL in vivo, we established hemangioendothelioma and melanoma tumor-bearing mouse model using node mice and administered with EA and Bu, tracked alterations in tumor volume and survival rate. Furthermore, tissue samples were obtained for histological, protein, and genetic investigations.

RESULTS

We demonstrate that the injection of EA and Bu, significantly inhibits tumor growth and prolongs the lifespan of tumor-bearing mice. Bu treatment exhibited a remarkable 33 % healing effect on the primary hemangioendothelioma tumor, bringing the survival rate to a level comparable to that of healthy mice. Mechanically, both EA and Bu impair respiratory chain complexes, leading to mitochondrial dysfunction and accumulation of reactive oxygen species (ROS), resulting in DNA damage, cell apoptosis, and finally blocked angiogenesis. While EA demonstrates robust inhibitory effects on cancer cell growth and a broader impact on metabolism in vitro, the in vivo effect of Bu surpasses that of EA in terms of strength. EA and Bu also exhibit potent anti-tumor effects on a primary melanoma model by inhibiting angiogenesis. Importantly, when compared to other compounds used in the treatment of hemangioendothelioma, EA and Bu demonstrate more profound anti-tumor effects.

CONCLUSION

For the first time, our findings reveal that EHL extracts, especially the high polarity compounds, exhibit potent anti-tumor effects by targeting cellular metabolism, specifically through the inhibition of mitochondria-related metabolic activities. This leads to the accumulation of ROS and effectively suppresses abnormal angiogenesis.

Sirolimus monotherapy for Kasabach-Merritt phenomenon in a neonate; Case report

INTRODUCTION AND IMPORTANCE

The Kasabach-Merritt Phenomenon (KMP), characterized by thrombocytopenia and consumptive coagulopathy due to endothelial cell growth in the infantile vascular tumor kaposiform hemangioendothelioma, presents a therapeutic challenge. This case highlights the novel use of sirolimus in a neonate, an approach less explored in this age group.

CASE PRESENTATION

A female neonate presented with a right anterior chest mass, progressing to respiratory distress and congestive heart failure. Diagnosed with KMP, she exhibited low platelet count and coagulation abnormalities. Treatment with sirolimus (0.06 mg/day) led to mass reduction, improved bleeding, and a stable tumor after 12 months, without side effects. This case contrasts with existing literature advocating for combination therapy or higher sirolimus concentrations for effective treatment. Yet, our patient achieved favorable outcomes with low-dose monotherapy, suggesting a potentially safer approach in neonates with immature hepatic and renal metabolism.

CLINICAL DISCUSSION

This case demonstrates the efficacy of low-dose sirolimus monotherapy in treating KMP in a neonate, challenging current preferences for combination therapies or higher doses. It emphasizes the need for further research into age-specific treatment protocols in KMP, considering the unique metabolic profiles of neonates and infants.

CONCLUSION

Sirolimus has demonstrated potential in treating KMP in pediatric patients. While initial results are promising, determining optimal dosages and trough concentrations, especially in neonates and infants, remains essential.

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.

Kaposiform hemangioendothelioma presented with raynaud phenomenon: a case report

BACKGROUND

Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm affecting infants or young children. KHE includes a spectrum of lesions, ranging from small and superficial tumors to large and invasive lesions with Kasabach-Merritt phenomenon (KMP). Currently, no published studies have reported a KHE presenting as thrombocytopenia and Raynaud phenomenon.

CASE PRESENTATION

A 2-year-old boy with right hand swelling and thrombocytopenia was admitted to our hospital. His right hand turned swelling and red, even occasionally cyanotic. This condition became worse in response to cool environments and improved with warming, and platelet counts were between 50 ~ 80 × 10^9/L. Physical examination on admission revealed the swelling and frostbite-like rash of the right-hand fingers, and the skin temperature of the right hand was lower than the left. On day 3 of admission, chest CT results showed an irregular mass on the right side of the spine. The puncture biopsy demonstrated positive CD31, D2-40, and FLI1 immunohistochemical staining, but negative GLUT1 staining, confirming the diagnosis of KHE. Furthermore, endothelin-1 (ET1) expression levels significantly increased, and eNOS and A20 expression levels significantly decreased comparing with control patients. The patient received methylprednisolone and sirolimus treatments, and his condition gradually improved during the follow-up.

CONCLUSIONS

We reported the first case of KHE presenting with thrombocytopenia and Raynaud phenomenon. The development of Raynaud phenomenon could be associated with increased ET-1 and reduced eNOS and A20 expressions. Careful differential diagnosis of hidden KHE should be considered in children with thrombocytopenia and Raynaud phenomenon.

Effective low-dose sirolimus regimen for kaposiform haemangioendothelioma with Kasabach-Merritt phenomenon in young infants

AIMS

Management of kaposiform haemangioendotheliomas (KHE) with Kasabach-Merritt 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 such as 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 5 infants with kaposiform haemangioendothelioma with Kasabach-Merritt 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 4 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-Merritt phenomenon resolved, the coagulation profile normalized and tumour size reduction was seen.

CONCLUSION

Low-dose sirolimus treatment is safe for infants with kaposiform haemangioendothelioma and Kasabach-Merritt phenomenon. It is essential 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.

Case report: Kaposi hemangioendothelioma of the right upper limb with the Kasabach-Merritt phenomenon: A potentially lethal diagnostic challenge

Kaposi hemangioendothelioma (KHE) is a rare vascular neoplasm that presents usually within the first year of life. Because of its rarity and complexity, there is often a delay in diagnosis. KHE could be associated with a life-threatening consumptive coagulopathy named the Kasabach-Merritt phenomenon (KMP). Here, we present the case of a 2-month-old girl who presented with progressive redness and swelling of her right upper limb over 6 weeks. Multiple health practitioners misdiagnosed her condition as an insect bite, cellulitis, and necrotizing fasciitis and gave treatment accordingly, which proved futile. A full blood count revealed bicytopenia of anemia and thrombocytopenia, a normal coagulation cascade, low fibrinogen, and raised D-Dimer levels. The imaging was suggestive of a high-flow vascular tumor likely to be a KHE. Subsequently, she was started on single-agent oral sirolimus with a dose increment to achieve satisfactory therapeutic levels and was treated for 1 year. She successfully completed the treatment regimen and had only transient hypertriglyceridemia, which resolved upon the completion of treatment. Currently, she is in remission 3 years after treatment. Keeping her case as an example, we would like to highlight the potentially lethal misdiagnosis of KHE with KMP, the importance of an early diagnosis of this condition, and the successful treatment outcome with single-agent sirolimus.

Sirolimus treatment for neonate with blue rubber bleb nevus syndrome: A case report

BACKGROUND

Blue rubber bleb naevus syndrome (BRBNS) is a rare disease that usually presents with multiple venous malformations in the skin and gastrointestinal tract. Lesions located in the gastrointestinal tract always result in chronic gastrointestinal bleeding and severe anemia. The successful management of BRBNS with sirolimus had been reported in many institutions, due to its impact on signaling pathways of angiogenesis. However, the experience in treatment of neonates with BRBNS was limited.

CASE SUMMARY

A 38-day-old premature female infant born with multiple skin lesions, presented to our center complaining of severe anemia and hematochezia. Laboratory examination demonstrated that hemoglobin was 5.3 g/dL and contrast-enhanced abdominal computed tomography showed multiple low-density space-occupying lesions in the right lobe of the liver. She was diagnosed as having BRBNS based on typical clinical and examination findings. The patient was treated by transfusions twice and hemostatic drugs but symptoms of anemia were difficult to alleviate. A review of BRBNS case reports found that patients had been successfully treated with sirolimus. Then the patient was treated with sirolimus at an average dose of 0.95 mg/m²/d with a target drug level of 10-15 ng/mL. During 28 mo of treatment, the lesion was reduced, hemoglobin returned to normal, and there were no adverse drug reactions.

CONCLUSION

This case highlights the dosing regimen and plasma concentration in neonates, for the current common empiric dose is high.

[Clinical features of Kasabach-Merritt syndrome: an analysis of 16 neonates]

OBJECTIVE

To study the clinical features, treatment, and prognosis of neonates with Kasabach-Merritt syndrome (KMS), and to provide a reference for optimizing the diagnosis and treatment of this disease.

METHODS

A retrospective analysis was performed for the clinical and follow-up data of 16 neonates with KMS who were admitted to the Anhui Children's Hospital, Anhui Medical University, from January 2016 to December 2020.

RESULTS

Of the 16 neonates, there were 13 boys (81%) and 3 girls (19%), with an age of 1 hour to 10 days on admission. Among these neonates, 13 (81%) had cutaneous hemangioma (2 in the head and face, 5 in the trunk, and 6 in the extremities) and 3 (19%) had liver hemangioma. The main clinical manifestations of bleeding tendency and scattered petechiae and ecchymosis were observed in 10 neonates (62%). All the 16 neonates had varying degrees of thrombocytopenia and coagulation disorders. They all received glucocorticoid treatment after admission and 7 (44%) of them had response, among whom 4 experienced recurrence. Among the neonates with no response to glucocorticoid treatment, 3 received sirolimus treatment, among whom 1 had the tumor volume reduced by 58.8% after 4 weeks of treatment, with platelet count and coagulation function returning to normal, while 2 had no significant reduction in tumor volume or significant increase in platelet count and achieved a tumor volume reduced by (43.7±0.4)% after 4 weeks of combined treatment with bleomycin arterial embolization, with platelet count and coagulation function returning to normal. After 4 weeks of bleomycin arterial embolization alone for 4 neonates, tumor volume was reduced by (52.0±3.4)%, and platelet count and coagulation function returned to normal. Blunt and sharp dissection was performed for 2 neonates. The tumor was removed completely during surgery in the 2 neonates, with no infection or recurrence after surgery, and platelet count and coagulation function returned to normal. The postoperative pathological examination showed Kaposiform hemangioendothelioma in 1 out of the 2 neonates.

CONCLUSIONS

KMS has characteristic clinical manifestations, histopathological features, and laboratory examination results. The KMS neonates who are not sensitive to glucocorticoids can achieve a good curative effect through arterial embolization and sirolimus treatment.