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Purpose Most new nasopharyngeal cancer cases occur in low-income and middle-income countries, and these patients experience poorer overall survival than that of new nasopharyngeal cancer cases in high-income countries. The goal of this research project is to determine whether the introduction of a radiation therapy quality assurance program can ultimately improve outcomes for nasopharyngeal cancer patients in lower-income and middle-income countries. This study reports the results of the first phase of the International Atomic Energy Agency Coordinated Research Project (325-E3-TM-47712). Methods and Materials This prospective study has 2 phases. Phase 1 is a survey of radiation therapy resources, patient characteristics and treatment, and results of radiation therapy quality assurance performed by the expert panel. An educational workshop reviewing phase 1 results for each center was completed before accrual of patients for phase 2. The ultimate aim of the study is to compare the first and second cohort of patients to see if quality assurance can result in fewer major protocol deviations and a 15% improvement in patients’ 3-year progression-free survival. Results Of 14 participating centers, 13 (93%) had computed tomography simulators and linear accelerators (LINAC) with intensity modulated radiation therapy (IMRT) capacity, median 3 LINAC (range, 1-13), and median 10 radiation oncologists (range, 5-51). The annual number of nasopharyngeal cancer cases irradiated was median 54 (range, 10-627). Five of 14 centers (36%) had no local radiation therapy quality assurance. For the current phase 1 study, 134 patients were evaluated, 82.1% had MRI staging, 99.3% had metastatic workup, 65.6% undifferentiated histology, 51% stage 3 and 49% stage 4. Radiation therapy quality assurance revealed 81 (60.4%) of 134 patients had major protocol violations in gross tumor volume and high dose planning target volume contours and/or dosimetry, 28.4% patients had borderline plans, 15 (11.2%) acceptable, and only 6 (4.2%) had inevitable compromise due to tumor extent. Conclusions This is the first International Atomic Energy Agency study to address the fundamental issue of treatment quality rather than altered treatment regimens. The high rate of unacceptable radiation therapy plans is a major concern, and we hope phase 2 will show a significant reduction and improved patient outcomes.

Purpose This study aimed to estimate the treatment outcome of nasopharyngeal cancer (NPC) across the world and its correlation with access to radiation therapy (RT). Methods and Materials The age-standardized mortality (ASM) and age-standardized incidence (ASI) rates of NPC from GLOBOCAN (2012) were summarized, and [1−(ASM/ASI)] was computed to give the proxy relative survival (RS). Data from the International Atomic Energy Agency (IAEA) and the World Bank were used to assess the availability of RT in surrogate terms: the number of RT equipment units and radiation oncologists per million population. Results A total of 112 countries with complete valid data were analyzed, and the proxy RS varied widely from 0% to 83% (median, 50%). Countries were categorized into Good, Median, and Poor outcome groups on the basis of their proxy RS ( 55%). Eighty percent of new cases occurred in the Poor outcome group. Univariable linear regression showed a significant correlation between outcome and the availability of RT: proxy RS increased at 3.4% ( P P =.001) per unit increase in RT equipment and oncologist per million population, respectively. The median number of RT equipment units per million population increased significantly from 0.5 in the Poor, to 1.5 in the Median, to 4.6 in the Good outcome groups, and the corresponding number of oncologists increased from 1.1 to 3.3 to 7.1 ( P Conclusions Nasopharyngeal cancer is a highly treatable disease, but the outcome varies widely across the world. The current study shows a significant correlation between survival and access to RT based on available surrogate indicators. However, the possible reasons for poor outcome are likely to be multifactorial and complex. Concerted international efforts are needed not only to address the fundamental requirement for adequate RT access but also to obtain more comprehensive and accurate data for research to improve cancer outcome.