End-to-End Test for a Radiotherapy Program Based on the Medical Linear Accelerator Installed in a Resource-Limited Oncology Centre in Sub-Saharan Africa

Abstract

Several challenges including the availability of necessary funds and expertise hinder the development and modernization of radiotherapy in resource-scarce countries like those in Sub-Saharan Africa (SSA). This work presents the findings of an end-to-end audit on independent verification of radiation doses delivered by a commercially available medical linear accelerator (linac) installed at Cameroon Oncology Center, a resource-constrained oncology centre in SSA. The medical linac with 6 MV and 18 MV x-rays, and five electron energies ranging from 6–20 MeV was commissioned for clinical use. The mailed TLD dosimetry irradiation systems based on the American Radiological Physics Center technique were used to check the output of the photon beams and electron energies. The end-to-end test was achieved by requesting, imaging and treating the MD Anderson anthropomorphic head and neck phantom using an IMRT technique on our linac. The phantom was irradiated and sent back to the USA for analysis. Evaluation criteria require that an institution’s treatment plan agree within ± 7% of measured TLD doses and that ≥ 85% of pixels pass ± 7%/4 mm gamma analysis for film. Beam output met the required criteria within ± 3%, and our institution’s treatment plan satisfied the established criteria of measured TLD doses and film dose distributions. The gamma-passing rate was ≥ 91%. A resource-constrained oncology centre in SSA has met the MD Anderson humanoid phantom irradiation criteria generally used for credentialing institutions to assure quality and safety of complex radiation treatments. Despite the various challenges faced by resource-constrained countries in SSA, this work demonstrates the practicability of implementing a modern radiotherapy program based on linear accelerator technology in a resource-limited region.