Increasing pediatric radiation oncology capacity in sub-saharan Africa using technology: a pilot of a pediatric radiation oncology virtual training course.

BACKGROUND: The shortage of skilled healthcare professionals in pediatric oncology and the limited access to training programs remain significant challenges in Nigeria and sub-Saharan Africa. The the Pediatric Radiation Oncology (Virtual) Course, 'PedROC' project aims to contribute to improving pediatric cancer outcomes in Nigeria by increasing the capacity of radiation oncology professionals. To address the gap in access to pediatric radiation oncology professional development, the PedROC project was created, harnessing technology to improve radiation oncology training via a curriculum delivered through web-conferencing. This study aimed to evaluate the effectiveness of the PedROC pilot in enhancing the capacity, confidence, and skill of radiation oncologists in decision-making, prescribing, and treatment planning of radiotherapy for children diagnosed with cancer. METHODS: A multidisciplinary faculty of specialists in radiation oncology, pediatric oncology, oncology nursing, radiation therapy technology, and medical physics collaborated to identify the key learning needs in pediatric radiation oncology in the country. The team collaborated to develop a comprehensive curriculum covering the most common pediatric cancers in sub-Saharan Africa for the training program. The training course was conducted over two days, delivering twenty-four half-hour sessions for a total of 12 h, from July 31 to August 01, 2021. RESULTS: Analysis of pre and post - training surveys showed a significant increase in self-reported confidence measures across all domains among radiation oncologists. The program successfully improved participants' knowledge and confidence levels in managing common pediatric cancers using radiotherapy, particularly addressing radiotherapy-specific issues such as appropriate dose, target volume delineation, treatment planning, dose constraints, and plan evaluation. CONCLUSION: The PedROC pilot showed the efficacy of this model in enhancing the capacity and confidence of radiation oncology professionals involved in the treatment of pediatric cancer. The findings indicate that technology holds significant potential to increase pediatric radiation oncology capacity in Africa, ensuring improved access to proper treatment and ultimately improving pediatric cancer outcomes.

Feasibility and Safety of Implementing Volumetric Arc Therapy (VMAT) for Pediatric Craniospinal Irradiation in a Low-Middle-Income Region: The Nigerian Experience.

Purpose: Volumetric modulated arc therapy (VMAT) is a relatively new treatment technique in sub-Saharan Africa. Although craniospinal irradiation (CSI) in the pediatric population has been practiced in Nigeria for many years, the use of VMAT to deliver this treatment is previously undocumented. We reviewed the first set of patients to undergo CSI at a cancer center in Nigeria, detailing the treatment technique, the progress experienced, dose statistics achieved, treatment toxicities, and cancer outcomes to date. Methods and Materials: This was a prospective case series of 5 children with histologically diagnosed cancers requiring CSI whose parents consented to the study. They were recruited at evaluation and followed through the process of their therapy. Toxicity was monitored at weekly review appointments using the Common Terminology Criteria for Adverse Events version 5.0. Follow-up of the children will continue in the long-term effects clinic. Results: Five patients with a median age of 6 were recruited. Diagnoses were intracranial germ cell tumor (n = 2), medulloblastoma (n = 1), pineoblastoma (n = 1), and ependymoma (n = 1). For all patients, a dose of 36.0 Gy in 1.8 Gy daily fractions was prescribed to the entire neuraxis. A subsequent boost of 18 Gy (n = 4) to 19.8 Gy (n = 1) in 10 daily fractions to the primary tumor bed (n = 2) and posterior fossa (n = 2) was delivered. Four patients had chemotherapy before, during, or after radiation therapy. No patient experienced grade 3 or greater toxicity. Conclusions: Our results indicate great progress has been made in the delivery of CSI in Nigeria, demonstrating tolerable acute side effects using VMAT. This series suggests the feasibility of implementing VMAT technology in low- or middle-income countries. Additional follow-up will be needed to determine whether survival rates and chronic toxicity rates are similar to those reported in the literature.

The Landscape of Pediatric Radiation Oncology in Nigeria.

Radiation therapy (RT) is an essential part of the multidisciplinary treatment of pediatric cancer. Over the past five decades, significant advances have been made in the delivery of RT, with better dose delivery to disease targets while minimizing exposure to nearby organs at risk. These advances have led to improved treatment outcomes, increased survival, and reduced treatment-related toxicities. Advanced treatment techniques, however, require significant investment in infrastructural and personnel resources. This review documents what is currently available regarding expertise and infrastructure for pediatric radiation oncology practice in Nigeria. It was performed to serve as a foundation for the creation and design of tailored solutions (initiatives and policies) to increase pediatric radiation availability, accessibility, and equity in Nigeria and ultimately improve pediatric cancer treatment outcomes in the region.

Challenges and opportunities for implementing hypofractionated radiotherapy in Africa: lessons from the HypoAfrica clinical trial.

The rising cancer incidence and mortality in sub-Saharan Africa (SSA) warrants an increased focus on adopting or developing approaches that can significantly increase access to treatment in the region. One such approach recommended by the recent Lancet Oncology Commission for sub-Saharan Africa is hypofractionated radiotherapy (HFRT), which can substantially increase access to radiotherapy by reducing the overall duration of time (in days) each person spends being treated. Here we highlight challenges in adopting such an approach identified during the implementation of the HypoAfrica clinical trial. The HypoAfrica clinical trial is a longitudinal, multicentre study exploring the feasibility of applying HFRT for prostate cancer in SSA. This study has presented an opportunity for a pragmatic assessment of potential barriers and facilitators to adopting HFRT. Our results highlight three key challenges: quality assurance, study harmonisation and machine maintenance. We describe solutions employed to resolve these challenges and opportunities for longer term solutions that can facilitate scaling-up use of HFRT in SSA in clinical care and multicentre clinical trials. This report provides a valuable reference for the utilisation of radiotherapy approaches that increase access to treatment and the conduct of high-quality large-scale/multi-centre clinical trials involving radiotherapy. Trial registration: Not available yet.

A Dosimetric Comparison of Volumetric Modulated Arc Therapy and Intensity Modulated Radiotherapy in Patients Treated with Post-Mastectomy Radiotherapy.

Objective: Radiotherapy continues to play an important role in the management of breast cancer. This study compared the dosimetric differences between the techniques of intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) in breast cancer patients who had radiotherapy after mastectomy. Materials and Methods: Forty post-mastectomy patients (19 right-sided breast and 21 left-sided breast) treated with the IMRT technique using 7-9 fields who were re-planned with VMAT using 2 coplanar arc on the Varian Vital beam linear accelerator between January, 2020 and August, 2021 were included in this study. The patients received 42 Gy in 15 fractions to the chest wall, lymph nodes and supraclavicular nodes. The dosimetric parameter for planning target volume (PTV), organs at risk (OAR) and the integral dose to the body were analysed. Student's t-test for two independent means was used to analyse the dosimetric differences between the plans. Results: Clinical goals were achieved for both techniques. In terms of PTV coverage at 95% (IMRT: 712.17±233) vs (VMAT: 694.9±214) and the homogeneity index (IMRT: 0.075±0.04) vs (VMAT: 0.104±0.03), IMRT resulted in better dose coverage and homogeneity than VMAT. However, with the conformity index, no significant difference was seen. As regards the OARs, the mean doses, V5, V10, V20, V30, and V40 for the Ipsilateral-lung were lower in IMRT plans than in VMAT plans with a non-significant variation (p-values = 0.141, 0.416, 0.954, 0.443, and 1 respectively). Regarding the mean dose to the heart, low-dose volumes V5, V10, and high-dose volume V30 were significantly reduced in IMRT compared to VMAT. When comparing the dose to the contralateral breast, IMRT achieved a significantly lower mean dose than VMAT (2.9 vs 3.62, p = 0.0148). For MU, VMAT showed lower MU compared to IMRT with a non-significant difference. Conclusion: With IMRT, better PTV coverage, homogeneity and OAR sparing were observed. Additionally, VMAT resulted in a lower delivery time than IMRT. Overall, both techniques offered dosimetric qualities that were clinically acceptable.

Chest X-rays of newborns in a medical facility: variation between the entrance skin dose measurements using the indirect and direct methods for clinical dose audit.

PURPOSE: This study aims to determine the mean and 75th percentile entrance skin dose (ESDcal) from anteroposterior (AP) chest X-rays using machine parameters (indirect method). Also, a comparison was made between the ESDcal and already determined thermoluminescent dosimeter (TLD) measurements (ESDTLD) from a previous study from the same patients' data. In addition, the results were compared to similar articles, where the direct and indirect methods were used in estimating ESD to newborns. MATERIALS AND METHODS: The study determined the digital radiography (DR) X-ray machine output using a calibrated XR Multidetector (silicon photodiode). X-ray machine milliampere-seconds (mAs), peak kilovoltage (kVp), focus to detector distance (FDD) and focus to skin distance (FSD) were used from a previous study. The mean kVp and mAs were 56.63 (52-60) and 5.7 (5-6.3) and the patient thickness was 9.5 (8-11.5) cm. RESULTS: The mean ESDs of the newborn between 0 and 28 days were 0.67 ± 0.09 mGy, and the 75th percentile was 0.75 mGy. The effective dose (E) for the 40 patients was 0.19 mSv and the estimated prenatal cancer risk ranged from (5-24.7) 10-6 Sv-1. The variation between the indirect and the direct methods for assessing ESD was 39.6 (33.7-45.1)%. CONCLUSION: The 75th percentile ESD was the highest compared to the American College of Radiology-American Association of Physicists in Medicine-Society for Pediatric Radiology (ACR-AAPM-SPR), European Commission (EC) and United Kingdom (UK) reports. Comparison of both methods for assessing ESD was within 40% as compared to other studies. Based on the above results, the indirect method can be implemented for clinical dose audit.

Evaluation of Three-Dimensional Conformal Radiotherapy and Intensity Modulated Radiotherapy Techniques for Left Breast Post-Mastectomy Patients: Our Experience in Nigerian Sovereign Investment Authority-Lagos University Teaching Hospital Cancer Center, South-West Nigeria.

OBJECTIVE: This study aimed to evaluate the dosimetric properties of treatment plans obtained from three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy techniques (IMRT) plans for left chest wall breast cancer patients. MATERIALS AND METHODS: A total of 20 patients with left-sided chest wall radiotherapy were randomly selected with the dose prescriptions: 42 Gy and 45 Gy in 15 and 18 fractions, respectively. Treatment plans were obtained using 3D-CRT and IMRT for each patient. Five to seven beams were used for IMRT, while tangential beams were used for 3D-CRT. Planning target volume, Dnear-max (D2 ), Dnear-min (D98 ), Dmean, Homogeneity and Conformity Indices (HI and CI) were obtained. Similarly, mean doses to organs at risk (OAR), V5, V10, V20, V25 were generated from the dose-volume histogram and compared. RESULTS: IMRT showed a significant improvement in HI compared to 3D-CRT (p<0.0001). Although there was no significant difference in sparing of the left lung between both plans for high-dose volumes (V20: 18.2 vs 30.55, p<0.0001), (V25: 11.17 vs 28.12, p<0.0001). IMRT however showed supremacy to 3D-CRT with high-dose volumes for the heart, including V20 (4.44 vs 10.29, p = 0.02), V25 (2.08 vs 8.94, p = 0.002). 3D-CRT was better than IMRT in low-dose volumes for left lung (V5: 92.23 vs 56.60, p<0.001; V10: 60.98 vs 47.20, p = 0.04) and heart (V5: 57.45 vs 30.39, p = 0.004). CONCLUSION: IMRT showed better homogeneity and sparing of high-dose volumes to OAR than 3D-CRT. On the other hand, 3D-CRT showed a reduction of low-dose volumes to OARs than IMRT.