Radiation therapy is an important factor to improve survival in pediatric patients with head and neck rhabdomyosarcoma by enhancing local control: a historical cohort study from a single center

Abstract

Background: The purpose of this study is to analyze the influence of radiation therapy on survival in a historical cohort of 56 pediatric patients with head and neck rhabdomyosarcoma. Methods: A historical cohort of 56 pediatric patients with head and neck rhabdomyosarcoma from June 1st, 2013 to June 30th, 2019 was chosen. Clinical data and follow up results were collected including all diagnosis, treatment and prognosis information. Overall survival (OS) and event free survival (EFS) as time-to-event distributions were estimated with Kaplan-Meier method, and univariate analysis was performed with log rank test to detect differences between groups. Multivariate analysis was performed to explore the risk factors for survival with Cox proportional hazard model. Results: The media follow up time of all 56 patients was 31.8 months (range 3.5-74.6 months). There were 26 events during follow up, including 14 disease progressions and 12 relapses. The estimated 5-year OS of all patients was 69.9%, and the estimated 5-year EFS was 48.8%. Patients with radiation therapy as a component of the initial treatment plan had better 5-year OS and EFS compared with those without radiation therapy (OS 80.3% vs. 49.7%, p = 0.003 and EFS 63.9% vs. 21.9%, p < 0.001). In patients with events, those who received salvage radiation therapy had better 5-year OS compared with those who didn't (OS 66.0% vs. 31.2%, p = 0.033). On multivariate analysis, tumor size > 5 cm and non-initial radiation therapy were independent risk factors for OS in all patients, non-initial radiation therapy was an independent risk factor for EFS in all patients, and tumor size > 5 cm was an independent risk factor for OS in patients with events. Conclusions: Radiation therapy as a component of initial treatment can improve the OS and EFS in pediatric head and neck rhabdomyosarcoma patients by enhancing local control, and non-initial radiation therapy is an independent risk factor for OS and EFS. Salvage radiation therapy still can improve OS in patients with disease progression and relapse. Tumor size > 5 cm is an independent risk factor for OS in pediatric HNRMS patients with or without disease progression/relapse.

Risk Factors for Disease Progression and Prognosis Analysis in Pediatric Head and Neck Rhabdomyosarcoma Patients: a Historical Cohort Study From a Single Center

“…The importance of local control by surgery and/or RT has widely been reported and con rmed in this cohort [8,13,22]. We reported that non-initial RT impairs OS and EFS by causing local failure in this cohort.…”

“…Radiation therapy (RT) was recommended to all patients except for Group embryonal patients, and RT dose was determined according to the recommendation of Soft Tissue Sarcoma Committee of Children's Oncology Group. As previously stated [13], that in 40% (22/56) of our pediatric HNRMS patients RT was not included as a component of the initial treatment plan, which was mainly attributed to parental refusal due to concerns about long-term RT toxicity or blind con dence in chemotherapy alone.…”

“…The uniform diagnostic procedure, risk strati cation and treatment protocol for this cohort have been described in details in our previously report [13]. Generally, site, size, primary tumor invasiveness, nodal involvement and metastatic status were determined by pretreatment imaging and test, and patient's stage was assigned according to the pretreatment staging system of Soft Tissue Sarcoma Committee of Children's Oncology Group [14].…”

Comparison of Definitive Radiotherapy-Based Treatment and Surgical-Based Treatment for Locally Advanced Head and Neck Soft Tissue Sarcoma

“…For some patients with locally advanced, or positive surgical margin diseases, postoperative adjuvant radiotherapy and chemotherapy is usually adopted. Studies have shown that postoperative adjuvant radiotherapy could significantly improve local control [5] and prolong the survival time of patients [9,10]. Adjuvant systemic chemotherapies could improve the prognosis of patients, but their benefits must be weighed against related toxicities [4].…”

Translational Implications for Radiosensitizing Strategies in Rhabdomyosarcoma

“…Similarly, the European approach provides the use of eight cycles of a lower intensity vincristine and actinomycin-D (VA) for a low-risk disease, four cycles of ifosfamide, vincristine, and actinomycin-D (IVA) followed by five cycles of VA for the standard risk disease, nine cycles of IVA are used for a high-risk disease [ 30 ]. RT plays a critical role in the management and local control of RMS [ 33 , 34 ] as also suggested by the fact that omitting RT, the most common protocol deviation, is related to an increased risk of local disease progression and death [ 35 ]. Differences on the indications to RT exist between COG and EpSSG.…”