Abstract B028: Pediatric osteosarcoma in a resource-limited setting: Data from a sub-Saharan African centre in Nigeria
Adedayo Joseph, Adeseye M. Akinsete, Adewunmi Alabi, Ayodeji O. Ojetunde, Asepeoreoluwa AdeyemiAbstract
Background:
Pediatric osteosarcoma remains a major cause of cancer-related morbidity and mortality among children and adolescents in sub-Saharan Africa, where late presentation, limited diagnostic resources, and restricted access to multimodal therapy significantly affect outcomes. There is a lack of region-specific data describing the epidemiology, clinical characteristics, and treatment patterns of this disease in low-resource settings.
Methods:
We conducted a retrospective descriptive study of pediatric patients (≤21 years) diagnosed with osteosarcoma at a sub-Saharan African cancer centre between September 2019 and May 2025. Data were extracted from medical records and institutional databases. The Cox proportional hazards model and Kaplan-Meier survival analysis were used to predict survival.
Results:
45 pediatric patients were identified. The median age at diagnosis was 15 years (range: 5-21), with a male predominance (55.6%). The majority of patients presented with advanced (66.7% ≥ stage III) or metastatic disease (51%), most commonly involving the lungs (82.6%). The long bones of the lower extremity (62.2%), particularly the distal femur (28.9%) and proximal tibia (22.2%), were the most frequently affected primary sites. Delayed presentation was common, with prolonged symptom duration prior to diagnosis (average 290 days). Surgery was performed in 31.1% (n=14). Chemotherapy formed the backbone of management, with 34 (75.6%) patients receiving systemic therapy in neoadjuvant (21, 46.7%), adjuvant (12, 26.7%), or concurrent chemotherapy (11, 24.4%) settings. Radiotherapy (RT) was administered to 27 patients (60%), functioning mostly as a curative modality in 71.1% (20/27), mainly with 3DCRT in 55.6% and IMRT in 44.4%. RT treatment completion was achieved in 26 patients (96.3%). The 1-year survival rate was 58.2%. The mean and median overall survival (OS) were 52.8 months (95% CI: 33.6-72.0) and 16.6 months (95% CI: 11.8-21.4), respectively. Survival did not differ significantly by age, sex, laterality, stage, or treatment type.
Conclusion:
Pediatric osteosarcoma in this cohort was characterized by prolonged diagnostic intervals, advanced-stage disease, and high metastatic burden at presentation, reflecting persistent systemic gaps in timely cancer diagnosis and access to comprehensive sarcoma care. High radiotherapy completion rates and the delivery of multimodal treatment in a proportion of patients, however, demonstrate the feasibility of structured oncologic care within resource-limited settings. These findings re-emphasize the impact of system-level constraints and the need for strengthened early diagnosis and referral pathways, diagnostic capacity, and access to multidisciplinary treatment in order to improve survival for pediatric osteosarcoma across sub-Saharan Africa.
Citation Format:
Adedayo Joseph, Adeseye M. Akinsete, Adewunmi Alabi, Ayodeji O. Ojetunde, Asepeoreoluwa Adeyemi. Pediatric osteosarcoma in a resource-limited setting: Data from a sub-Saharan African centre in Nigeria [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Bridging Discovery and Clinical Impact in Pediatric Cancer; 2026 Sep 22-25; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2026;86(18_Suppl_1):Abstract nr B028.