Paediatric soft tissue sarcomas in a resource constraint setting: Grade and stage at presentation and at oncologic intervention are usually of poor prognostic characteristics

Aim: To describe the pattern of paediatric Rhabdomyosarcomas (RMS) and Non-Rhabdomyosarcomas (NRMS) with emphasis on the indices that affect survival outcomes.

Methods: We reviewed all patients with histologically confirmed RMS and NRMS in the Departments of Pathology and Paediatrics, University College Hospital (UCH), Ibadan, Nigeria; in children aged 0-14 years. The study period was January 1991 to December 2016. Information obtained included age, gender, morphology and site of the tumours. The tumour grade and pathologic/clinical staging of all patients were also obtained and verified by the clinical records. Tumour grading was carried out using the Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) Sarcoma group grading system and staging was done using TNM. Follow up, survival information and final outcome were retrieved.

Results: The 104 patients included in the study had almost equal male-to-female ratio, age ranged between 5 months and 14 years (median 8.2 years). Rhabdomyosarcoma had mean age of 5.6 (±3.8) years while that of NRMS was 9.2(±4.1) years. Overall, the modal age group was 5-9 years. Rhabdomyosarcoma was the commonest histological type (76%), undifferentiated sarcomas (6.7%), fibrosarcoma (3.8%) and 2.9% each for synovial sarcoma and dermatofibrosarcoma protuberans. The common primary sites were the head and neck (including the orbit) 49 (47.1%), and the abdominopelvic 26 (25%) regions. Majority (89%) had histologic grade 3 at presentation. Seventy per cent and 64% of patients with RMS and NRMS, respectively, had high stage tumour at presentation. Median survival for all patients with Rhabdomyosarcoma was 45 weeks with a 1-year survival of 43% and 2-year survival of 25%. Non-RMS (Dermatofibrosarcoma protuberans and Solitary fibrous tumours) had survival of over 4 year's duration.

Conclusion: Majority of our patients presented at a late stage with histologic high grade which confers poor prognosis and reduced chances for good overall survival outcome.