背景:环磷酰胺总剂量增加至26.4g/m2后,在组间横纹肌肉瘤研究IV中,低危横纹肌肉瘤患者的无失败生存率(FFS)得到改善。然而,这种剂量可能会增加不良事件的风险,包括不孕症,在一些病人。JRS-ILRA0401和LRB0402方案旨在将环磷酰胺剂量分别降低至9.6g/m2和17.6g/m2,而不降低FFS率。
方法:亚组A患者接受8个周期(24周)的长春新碱,放线菌素D,和1.2g/m2/周期的环磷酰胺。B亚组患者接受8个周期(24周)的长春新碱,放线菌素D,和2.2g/m2/周期环磷酰胺,随后是6个周期(24周)的长春新碱和放线菌素D.两个亚组的II/III组患者均接受放疗.
结果:在A亚组(n=12)中,3年FFS率为83%(95%置信区间[CI],48-96),3年总生存率(OS)为100%。仅观察到一次孤立的局部复发(8.3%)。没有意外的4级毒性,也没有死亡。在B亚组(n=16)中,3年FFS和OS率分别为88%(95%CI,59-97)和94%(95%CI,63-99),分别。没有意外的4级毒性,也没有死亡。
结论:使用长春新碱的短期治疗,放线菌素D,对于低危亚组横纹肌肉瘤(JRS-ILRA0401方案)患者,低剂量环磷酰胺联合或不联合放疗,对于低危亚组B横纹肌肉瘤患者,适度减少环磷酰胺剂量(JRS-ILRB0402方案)均未影响FFS.
BACKGROUND: Failure-free survival (FFS) rates of low-risk patients with rhabdomyosarcoma improved in Intergroup Rhabdomyosarcoma Study IV after the escalation of cyclophosphamide total dose to 26.4 g/m2. However, this dose may increase the risk of adverse events, including infertility, in some patients. The JRS-I LRA0401 and LRB0402 protocols aimed to reduce the cyclophosphamide dose to 9.6 g/m2 and 17.6 g/m2, respectively, without decreasing the FFS rates.
METHODS: Subgroup-A patients received eight cycles (24 weeks) of vincristine, actinomycin D, and 1.2 g/m2/cycle cyclophosphamide. Subgroup-B patients received eight cycles (24 weeks) of vincristine, actinomycin D, and 2.2 g/m2/cycle cyclophosphamide, followed by six cycles (24 weeks) of vincristine and actinomycin D. Group II/III patients in both subgroups received radiotherapy.
RESULTS: In subgroup A (n = 12), the 3-year FFS rate was 83% (95% confidence interval [CI], 48-96), and the 3-year overall survival (OS) rate was 100%. Only one isolated local recurrence was observed (8.3%). There were no unexpected grade-4 toxicities and no deaths. In subgroup B (n = 16), the 3-year FFS and OS rates were 88% (95% CI, 59-97) and 94% (95% CI, 63-99), respectively. There were no unexpected grade 4 toxicities and no deaths.
CONCLUSIONS: Shorter duration therapy using vincristine, actinomycin D, and lower dose cyclophosphamide with or without radiotherapy for patients with low-risk subgroup A rhabdomyosarcoma (JRS-I LRA0401 protocol) and moderate reduction of cyclophosphamide dose for patients with low-risk subgroup B rhabdomyosarcoma (JRS-I LRB0402 protocol) did not compromise FFS.