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
Paul Njom Mobit,
Paulin Harmoniel Imandi,
Nicholas Ade
Issue:
Volume 8, Issue 2, June 2022
Pages:
22-29
Received:
2 May 2022
Accepted:
14 May 2022
Published:
31 May 2022
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.
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 medic...
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Commissioning Experience of a Medical Linear Accelerator in a Low-Resource Setting in Sub-Saharan Africa
Paul Njom Mobit,
Nicholas Ade
Issue:
Volume 8, Issue 2, June 2022
Pages:
30-37
Received:
5 May 2022
Accepted:
28 May 2022
Published:
9 June 2022
Abstract: With increasing cancer incidence in Africa, a number of Sub-Saharan African countries have started implementing radiotherapy programs based on linear accelerator (linac) technology. This work summarizes the commissioning experience of a commercially available medical linac installed in a resource-limited oncology centre in Cameroon for the delivery of high-quality radiation treatments to cancer patients in central Africa. Cameroon is a central African country in Sub-Saharan Africa. Using a 2D water phantom and various ionization chambers, we measured commissioning data for a medical linac with 6X and 18X photon beams, and five electron energies ranging from 6–20 MeV. Relative measurements included percent depth doses (PDDs), beam profiles, scatter factors, wedge factors, and electron cone factors. Absolute calibrations of the beam energies were performed using the American Association of Physicist in Medicine Task Group Report 51. Accurate calibrations were checked by irradiating the mailed thermoluminescent dosimeters service offered by MD Anderson Cancer Center. Photon PDDs agreed within 1% of the average of several linacs of the same type at depths between 5 and 20 cm, which are consistent with the data used by the manufacturer for acceptance testing. For electrons, the agreement was within 2 mm for R50, R90, Rp, and dmax. Symmetry and flatness for all photon and electron beams were within 2% for various fields. All absolute calibrations met the MD Anderson Cancer Center criteria within 3%. This work presents the successful implementation and modernization of a radiotherapy program based on linac technology in the central African sub-region in Sub-Saharan Africa. As the first operational medical linac in the sub-region, the commissioning data can provide comparison data to other linacs in the future to ensure high-quality of machine commissioning for clinical use.
Abstract: With increasing cancer incidence in Africa, a number of Sub-Saharan African countries have started implementing radiotherapy programs based on linear accelerator (linac) technology. This work summarizes the commissioning experience of a commercially available medical linac installed in a resource-limited oncology centre in Cameroon for the delivery...
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