[A multicenter study on childhood Hodgkin lymphoma treated with HL-2013 regimen in China].

Objective: To evaluate the efficacy of the Hodgkin lymphoma (HL)-2013 regimen in the treatment of children with HL, and to investigate the prognostic factors of childhood HL. Methods: Clinical data of 145 children (aged ≤18 years) with newly diagnosed HL, treated with HL-2013 regimen in 8 tertiary referral centers for childhood cancer from August 2011 to April 2021 were analyzed retrospectively. All the diagnosis were confirmed by histopathological morphology and immunohistochemical examination. The clinical characteristics and treatment outcomes were summarized, and the patients were divided into different groups according to clinical characteristics. Kaplan-Meier method was used for survival analysis, and the comparison of survival rates between groups was performed with Log-rank test. Results: Of the 145 cases, there were 115 males and 30 females, the age at diagnosis was 7.9 (5.8, 10.6) years. Cervical lymph node enlargement (114 cases, 78.6%) was the common symptom of the disease, and 57 patients (39.3%) were accompanied by large masses. The most common pathological classification was mixed cell type (93 cases, 64.1%). According to the Ann Arbor staging system, there were 9 cases of stage Ⅰ, 62 cases of stage Ⅱ, 45 cases of stage Ⅲ, 29 cases of stage Ⅳ. According to the risk stratification: there were 14 cases of low-risk group, 76 cases of medium-risk group and 55 cases of high-risk group. Of all patients, 68 cases (46.9%) achieved an early complete remission (CR) after 2 courses of chemotherapy, and the CR rate was 93.8% (136/145) after first-line treatment. Disease recurrence or progression occurred in 22 cases (15.2%). Of all patients, 125 cases survived, 6 cases died and 14 cases were lost to follow-up. Among the survived cases, 123 cases were continuously at CR state,and the follow-up time was 55 (40, 76) months. The 5-year overall survival (OS) and event free survival (EFS) rates were (95.3±1.9)% and (84.2±3.0)% for the entire group, respectively. 5-year OS and EFS rates for patients with stage Ⅲ-Ⅳ were both lower than those for patients with stage Ⅰ-Ⅱ (χ2=6.28 and 7.58, both P<0.05), the 5-year OS and EFS rates for patients in high-risk group were both lower than those for patients in low-risk and medium-risk group (χ2=10.93, 7.79, both P<0.05). The 5-year OS rates for the patient with early CR and without early CR were 100.0% and (90.9±3.6)% (χ2=5.77, P=0.016). EFS rates for the patient with early CR (68 cases) and without early CR (77 cases) were (93.8±3.0)% and (75.8±5.0)% (χ2=8.78, P=0.003). Conclusions: HL-2013 regimen is significantly effective in the treatment of pediatric HL. However, the patients in high-risk group and those without early CR are prone to disease recurrence or progression. Stage Ⅲ-Ⅳ and without early CR were associated with worse prognosis.