Clinical efficacy and safety of mTOR inhibitor in patients with advanced unresectable epithelioid hemangioendothelioma (EHE).

Huijing Tan Cancer Hospital Chinese Academy of Medical Sciences, Beijing, China info_outline Huijing Tan, Yuting Sun, Yihebali Chi

Authors Huijing Tan Cancer Hospital Chinese Academy of Medical Sciences, Beijing, China info_outline Huijing Tan, Yuting Sun, Yihebali Chi Organizations Cancer Hospital Chinese Academy of Medical Sciences, Beijing, China, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital,Chinese Academy of Medical Science,Peking Union Medical College, Beijing, China Abstract Disclosures Research Funding No funding sources reported Background: Epithelioidhemangioendothelioma is a rare vascular soft tissue sarcoma, 90% of which contains WWTR1-CAMTA1 fusion gene. Studies have shown that mTOR inhibitors may have a certain effect on EHE patients. Methods: A retrospective analysis of the efficacy and safety of mTOR inhibitor everolimus in the treatment of advanced unresectable epithelioidhemangioendothelioma in our hospital in the past one year. Patients with advanced epithelioidhemangioendothelioma (EHE) confirmed by consultation in the pathological center received this regimen, everolimus 10mg, once a day orally for 28 days, every 4 weeks as a treatment cycle until the disease progressed or showed intolerable toxicity. Results: There were 3 females and 5 males, and their average age was 41.8 years old. All of them were unresectable with liver, lung, and shoulder primary lesions, and lungs, liver, pleura and bone metastasis. Ki67 is from 2% to 10%. 3 patients who received molecular pathological examination were all identified the WWTR1-CAMTA1 fusion gene, and one of them also had EWSR1 chromosome translocation. Previous antineoplastic treatments included gemcitabine, cisplatin, albumin paclitaxel, epirubicin, dacarbazine chemotherapy, anlotinib targeting, and toripalimab immune therapy. 5 patients were treated with first-line drugs, 2 cases with second-line and 1 case with third-line. In terms of overall efficacy, 1 case was not evaluated, 2 cases lost follow-up due to poor tolerance and economic factors, 2 cases were included in the clinical trails after reaching tumor control for 3 months, and the other 3 cases achieved tumor remission with a median PFS of 11.0 months, and the best curative effect was SDa. Severe oral mucositis can greatly affect the medication experience of patients, which can be relieved after symptomatic medication, or when interstitial pneumonia and hemogram decrease significantly, we can consider the oral administration of everolimus 5mg. Conclusions: At present, there is no standard treatment for EHE, we can roughly see the efficacy of mTOR inhibitor everolimus in some EHE patients, mainly disease stability. Emphasis on side effect management, improve tolerance, and systematic treatment of EHE needs to be further explored.