Bone tumors account for approximately 6% of all cancers in children. Malignant bone tumors, commonly occurring in children and adolescents, are associated with high mortality and morbidity. The overall survival of children with primary malignant bone tumors is affected by the stage of disease, time of diagnosis, and treatment response. Despite advanced treatment modalities with chemotherapy, surgery, and radiotherapy, bone tumor is the third leading cause of death in children with malignancy. Patients with metastatic disease at diagnosis have poor outcomes compared to localized disease at presentation. The 5-year Overall Survival and event-free survival in children with primary malignant bone tumors were 85.2% and 69.2%. The study aimed to assess the clinicopathological profile and treatment outcomes of children with primary malignant bone tumors in our setup. A hospital-based cross-sectional study was conducted on 95 children who met the inclusion criteria through structured questionnaire. The collected data were analyzed using a statistical package for social sciences (SPSS) version 25. P-value < 0.05 was considered to be statistically significant. Kaplan Meier survival estimate was used for overall and event-free survival analysis. A total of ninety-five patients met the study inclusion criteria and the median age at diagnosis with primary malignant bone tumors was 10 years, with an interquartile range of 8–12 years. The duration of the illness from the onset of symptoms to the oncologic treatment center ranges from three weeks to 2 years with a mean duration of five months. Swelling was the commonest presenting symptom accounting for 95.8% (n = 91). Lower extremity was the commonest primary site of involvement accounting for 55.8% (n = 53) of children with primary malignant bone tumors. Osteosarcoma was the commonest malignant bone tumor constituted 66.3% (n = 63), followed by Ewing sarcoma at 33.7% (n = 32). About 41.2% (n = 39) of children had metastatic disease at presentation and the lung was the commonest site of distant metastasis. The Kaplan Meier survival estimate analysis showed the 1-year and 5-year overall survival probabilities for all pediatric primary malignant bone tumor patients were 65% (95% CI: 0.3–0.56) and 38% (95% CI:0.19–0.47) respectively. The 1-year and 5-year event-free survival probabilities were 55% (95% CI: 0.32–0.73) and 33% (95% CI: 0.10–0.59). The stage of the disease at presentation had a significant association with the outcome (p = 0.023). Our study showed the mean duration of the illness from the onset of symptoms to the oncologic treatment center was 5 months ranging from 3 weeks to 2 years. More than one-third of the presented with metastatic disease at presentation. The 1-year and 5-year overall survival (OS) probabilities of children with primary malignant bone tumors were low in our setup compared to other studies.

中文翻译：

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埃塞俄比亚三级转诊医院儿童原发性骨肿瘤的模式和治疗结果

骨肿瘤约占儿童所有癌症的 6%。恶性骨肿瘤常见于儿童和青少年，死亡率和发病率较高。原发性恶性骨肿瘤儿童的总生存率受到疾病阶段、诊断时间和治疗反应的影响。尽管采用化疗、手术和放疗等先进治疗方式，骨肿瘤仍是恶性肿瘤儿童的第三大死因。与就诊时的局部疾病相比，诊断时患有转移性疾病的患者预后较差。原发性恶性骨肿瘤儿童的5年总生存率和无事件生存率分别为85.2%和69.2%。该研究旨在评估我们设置中患有原发性恶性骨肿瘤的儿童的临床病理学特征和治疗结果。通过结构化问卷对 95 名符合纳入标准的儿童进行了一项以医院为基础的横断面研究。使用社会科学统计软件包 (SPSS) 25 版对收集的数据进行分析。P 值 < 0.05 被认为具有统计显着性。 Kaplan Meier 生存估计用于总体生存和无事件生存分析。共有 95 名患者符合研究纳入标准，诊断原发性恶性骨肿瘤的中位年龄为 10 岁，四分位数范围为 8-12 岁。从出现症状到到肿瘤治疗中心的病程从三周到两年不等，平均持续时间为五个月。肿胀是最常见的症状，占 95.8% (n = 91)。下肢是最常见的原发部位，占原发性恶性骨肿瘤儿童的 55.8% (n = 53)。骨肉瘤是最常见的恶性骨肿瘤，占 66.3% (n = 63)，其次是尤文肉瘤，占 33.7% (n = 32)。约 41.2% (n = 39) 的儿童就诊时患有转移性疾病，肺部是最常见的远处转移部位。 Kaplan Meier 生存估计分析显示，所有儿童原发性恶性骨肿瘤患者的 1 年和 5 年总生存概率分别为 65%（95% CI：0.3–0.56）和 38%（95% CI：0.19–0.47）分别。 1年和5年无事件生存概率分别为55%（95% CI：0.32-0.73）和33%（95% CI：0.10-0.59）。就诊时的疾病分期与结果显着相关（p = 0.023）。我们的研究显示，从出现症状到到肿瘤治疗中心的平均病程为 5 个月，从 3 周到 2 年不等。超过三分之一的患者就诊时患有转移性疾病。与其他研究相比，我们的研究中原发性恶性骨肿瘤儿童的 1 年和 5 年总生存 (OS) 概率较低。