Oral vinorelbine and continuous low doses of cyclophosphamide in pediatric rhabdomyosarcoma: a real-world study

Yingxia Lan; Liuhong Wu; Ye Hong; Xiaofei Sun; Juan Wang; Junting Huang; Feifei Sun; Jia Zhu; Zijun Zhen; Yizhuo Zhang; Mengjia Song; Suying Lu

doi:10.3389/fphar.2023.1132219

Oral vinorelbine and continuous low doses of cyclophosphamide in pediatric rhabdomyosarcoma: a real-world study

Front Pharmacol. 2023 May 3:14:1132219. doi: 10.3389/fphar.2023.1132219. eCollection 2023.

Authors

Yingxia Lan^{1

2}, Liuhong Wu^{1

2}, Ye Hong^{1

2}, Xiaofei Sun^{1

2}, Juan Wang^{1

2}, Junting Huang^{1

2}, Feifei Sun^{1

2}, Jia Zhu^{1

2}, Zijun Zhen^{1

2}, Yizhuo Zhang^{1

2}, Mengjia Song^{1

2}, Suying Lu^{1

2}

Affiliations

¹ Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
² Department of Pediatric Oncology, Sun Yat-sen University Cancer Center, Guangzhou, China.

Abstract

Introduction: Metronomic maintenance therapy (MMT) has significantly improved the survival of patients with high-risk rhabdomyosarcoma in clinical trials. However, there remains a lack of relevant data on its effectiveness in real-world situations. Methods: We retrospectively retrieved data of 459 patients < 18 years of age diagnosed with rhabdomyosarcoma at Sun Yat-sen University Cancer Center from January 2011 to July 2020 from our database. The MMT regimen was oral vinorelbine 25-40 mg/m² for twelve 4-week cycles on days 1, 8, and 15, and oral cyclophosphamide 25-50 mg/m² daily for 48 consecutive weeks. Results: A total of 57 patients who underwent MMT were included in the analysis. The median follow-up time was 27.8 (range: 2.9-117.5) months. From MMT to the end of follow-up, the 3-year PFS and OS rates were 40.6% ± 6.8% and 58.3% ± 7.2%, respectively. The 3-year PFS was 43.6% ± 11.3% in patients who were initially diagnosed as low- and intermediate-risk but relapsed after comprehensive treatment (20/57), compared with 27.8% ± 10.4% in high-risk patients (20/57) and 52.8% ± 13.3% in intermediate-risk patients who did not relapse (17/57). The corresponding 3-year OS for these three groups was 65.8% ± 11.4%, 50.1% ± 12.9%, and 55.6% ± 13.6%, respectively. Conclusion: We present a novel study of MMT with oral vinorelbine and continuous low doses of cyclophosphamide in real-world pediatric patients with RMS. Our findings showed that the MMT strategy significantly improved patient outcomes and may be an effective treatment for high-risk and relapsed patients.

Keywords: chemotherapy; metronomic maintenance therapy; pediatric; rhabdomyosarcoma; soft tissue sarcoma.

Grants and funding

This study was supported by the Medical Science and Technology Research Fund Project of Guangdong Province (number A2022079), the Basic and Applied Basic Research Foundation of Guangdong Province (number 2021A1515110234), the National Natural Science Foundation of China (number 82203303), and the National Natural Scientific Foundation of China (number 82203754).