Analysis of clinical characteristics and prognosis of children of less-than-2-year old with rhabdomyosarcoma

Objective\r\nTo summarize clinical characteristics, therapeutic effect and prognosis of rhabdomyosarcoma(RMS) children of less-than-2-year old and its related factors, to improve the awareness of this age group with RMS.\r\n\r\n\r\nMethods\r\nThe clinical information and therapeutic effect of 20 RMS patients of less-than-2-year old were diagnosed and treated at the hematology-oncology center in Beijing Children′s Hospital(BCH), from January 2012 to April 2017, and the clinical data were analyzed retrospectively.According to the international criteria for the treatment of solid tumors in children, the patients were divided into a complete remission group and a progress/relapse group, and the risk factors affecting the prognosis were analyzed.\r\n\r\n\r\nResults\r\nTwenty cases of less-than-2 year old children with RMS were collected, accounting for 12.4% of all RMS during the same period in BCH hematology-oncology center.The median follow-up time was(16.1±1.8) months, 5 patients got progress/relapse at 9-12 months during treatment and 2-3 months after therapy finished.The rate of 2-year-event-free survival (EFS) rate and overall survival(OS) rate were 48% and 61%, respectively.The 2-year EFS rate of embryonal RMS children was significantly higher than that of alveolar RMS children, and the difference was statistically significant (χ2=0.854, P=0.034). In the progress/relapse group and the children with complete remission children, factors like boy, embryonal type, primary tumor location of not bad, and of medium risk might reduce the risk of progress/relapse of RMS, while tumor diameter \u003e5 cm and clinical stage Ⅳ might increase the risk of progress/relapse of RMS, but the difference was not statistically significant (P\u003e0.05).\r\n\r\n\r\nConclusions\r\nThe prognosis of RMS children less-than-2-year old was very poor, and the rates of 2 years EFS and OS rates were lower than overall index of children with RMS.These patients need to undergo a variety of treatment methods flexibly, including delayed radiotherapy and 125I radioactive seeds brachytherapy, to improve therapeutic efficacy and long-term outcomes.\r\n\r\n\r\nKey words: \r\nInfant; Rhabdomyosarcoma; Therapeutic efficacy; Prognosis