Estimation of the optimal radiotherapy utilization rate for childhood neuroblastoma.

BACKGROUND AND PURPOSE: The optimal utilization rate of radiotherapy (oRUR) serves as a benchmark for assessing service demand and improving access to cancer care. While it is estimated that approximately 50 % of adult cancer patients require external beam radiotherapy during their treatment, there is a scarcity of data regarding the optimal use of radiotherapy in pediatric cancer. In this study, we adopted an established method and developed a model to estimate the oRUR in childhood neuroblastoma. MATERIALS AND METHODS: We developed a decision tree model to calculate the oRUR using indications for radiotherapy and corresponding epidemiological data collected through systematic review and meta-analysis. Sensitivity analyses were performed to evaluate the impact of variations in radiotherapy indications between treatment protocols and variables in the model. We calculated and compared the oRUR for global, high-income, and low- and middle-income settings. RESULTS: The oRUR for pediatric neuroblastoma was 64 % (95 % CI: 58 %-71 %) in the global setting, 50 % in high-income countries, and 68 % in low- and middle-income countries. The impact of variation in radiotherapy indications between major international treatment protocols was negligible. CONCLUSION: The knowledge of oRUR is crucial for evaluating current practices, identifying gaps in access, and planning future radiotherapy services for treating childhood cancer. Based on our results, 64 % of children with neuroblastoma have an indication for radiotherapy. Patients in low- and middle-income countries have more indications for radiotherapy than those in high-income countries, due to a more adverse tumour stage distribution caused by limited access to healthcare resources.

Global application of National Comprehensive Cancer Network resource-stratified guidelines for systemic treatment of colon cancer: a population-based, customisable model for cost, demand, and procurement.

BACKGROUND: Resource-stratified guidelines (RSGs) can inform systemic treatment decisions in the face of limited resources. The objective of this study was to develop a customisable modelling tool to predict the demand, cost, and drug procurement needs of delivering National Comprehensive Cancer Network (NCCN) RSG-based systemic treatment for colon cancer. METHODS: We developed decision trees for first-course systemic therapy for colon cancer based on the NCCN RSGs. Decision trees were merged with data from the Surveillance, Epidemiology, and End Results programme, the International Agency for Research on Cancer's GLOBOCAN 2020 national estimates for colon cancer incidence, country-level income data, and data on drug costs from Redbook (USA), the Pharmaceutical Benefits Scheme (Australia), and the Management Sciences for Health 2015 International Medical Products price guide to estimate global treatment needs and costs, and forecast drug procurement. Simulations and sensitivity analyses were used to explore the effect of scaling up services globally and the effect of alternative stage distributions on treatment demand and cost. We generated a customisable model, in which estimates can be tailored to local incidence, epidemiological, and costing data. FINDINGS: First-course systemic therapy is indicated in 608 314 (53·6%) of 1 135 864 colon cancer diagnoses in 2020. Indications for first-course systemic therapy are projected to rise to 926 653 in 2040; the indications in 2020 might be as high as 826 123 (72·7%), depending on stage distribution assumptions. Adhering to NCCN RSGs, patients with colon cancer in low-income and middle income countries (LMICs) would constitute 329 098 (54·1%) of 608 314 global systemic therapy demands, but only 10% of global expenditure on systemic therapies. The total cost of NCCN RSG-based first-course systemic therapy for colon cancer in 2020 would be between about US$4·2 and about $4·6 billion, depending on stage distribution. If all patients with colon cancer in 2020 were treated according to maximal resources, global expenditure on systemic therapy for colon cancer would rise to around $8·3 billion. INTERPRETATION: We have developed a customisable model that can be applied at global, national, and subnational levels to estimate systemic treatment needs, forecast drug procurement, and calculate expected drug costs on the basis of local data. This tool can be used to plan resource allocation for colon cancer globally. FUNDING: None.

Patterns of curative treatment for non-small cell lung cancer in New South Wales, Australia.

INTRODUCTION: There is a lack of large population-based studies examining patterns of curative treatment for non-small cell lung cancer (NSCLC) in Australia. This study aimed to evaluate the utilization of curative treatment for NCSLC at a population level and identify factors associated with its use in New South Wales (NSW), Australia. METHODS: Patients diagnosed with localized or locoregional NSCLC between 2009 and 2014 were identified from the NSW Central Cancer Registry. Curative treatment was defined as surgery or radiotherapy with a 45 Gy minimum dose. Univariate and multivariable analyses were performed to investigate factors associated with the receipt of curative treatment. A Cox proportional-hazards regression model was used to analyze the factors associated with 2-year overall survival (OS). RESULTS: Of the 5722 patients diagnosed with NSCLC in the study period, 3355 (59%) patients received curative treatment and 2367 (41%) patients did not receive curative treatment. The receipt of curative treatment was significantly associated with younger patients, female gender, localized disease, and Charlson Comorbidity Index (CCI) = 0. The use of curative treatment increased significantly over time from 2009 (55%) to 2014 (63%) and varied significantly from 24% to 70% between local health districts (LHDs) of residence. Younger age, female gender, localized disease, CCI = 0, and overseas country of birth were significantly associated with 2-year OS. The 2-year OS significantly improved from 70% in 2009 to 77% in 2014 for patients who received curative treatment. CONCLUSION: The use of curative treatment for patients with potentially curable NSCLC was low at 59%. However, the use of curative treatment and survival have increased over time. Significant variation was noted in the use of curative treatment between LHDs.

Repeatability and reproducibility of magnetic resonance imaging-based radiomic features in rectal cancer.

Purpose: Radiomics of magnetic resonance images (MRIs) in rectal cancer can non-invasively characterize tumor heterogeneity with potential to discover new imaging biomarkers. However, for radiomics to be reliable, the imaging features measured must be stable and reproducible. The aim of this study is to quantify the repeatability and reproducibility of MRI-based radiomic features in rectal cancer. Approach: An MRI radiomics phantom was used to measure the longitudinal repeatability of radiomic features and the impact of post-processing changes related to image resolution and noise. Repeatability measurements in rectal cancers were also quantified in a cohort of 10 patients with test-retest imaging among two observers. Results: We found that many radiomic features, particularly from texture classes, were highly sensitive to changes in image resolution and noise. About 49% of features had coefficient of variations ≤ 10 % in longitudinal phantom measurements. About 75% of radiomic features in in vivo test-retest measurements had an intraclass correlation coefficient of ≥ 0.8 . We saw excellent interobserver agreement with mean Dice similarity coefficient of 0.95 ± 0.04 for test and retest scans. Conclusions: The results of this study show that even when using a consistent imaging protocol many radiomic features were unstable. Therefore, caution must be taken when selecting features for potential imaging biomarkers.

Regional Variations in Clinical Trial Outcomes in Oncology.

BACKGROUND: It is unknown how often regional differences in oncology trials are observed. Based on our study findings, we quantified regional variation in registration studies in oncology and developed a question guide to help clinicians evaluate regional differences. METHODS: Using FDA archives, we identified registration studies in solid tumor malignancies from 2010 to 2020. We extracted the baseline study characteristics and participating countries and determined whether the primary publication reported a regional subgroup analysis. For studies presenting outcomes stratified by region, we extracted the stratified hazard ratios (HRs) and extracted or calculated the test for heterogeneity. We performed a random effects meta-analysis and a pairwise comparison to determine whether outcomes differed between high-income versus mixed-income regions. RESULTS: We included 147 studies in our final analysis. Studies supporting FDA drug approval have become increasingly multinational over time (ß = 0.5; P=.04). The median proportion of countries from high-income groups was 81.2% (range, 44%-100%), with no participation from low-income countries in our cohort. Regional subgroup analysis was presented for 78 studies (53%). Regional heterogeneity was found in 17.8% (8/45) and 18% (8/44) of studies presenting an overall survival (OS) and progression-free survival endpoint, respectively. After grouping regions by income level, we found no difference in OS outcomes in high-income regions compared with mixed-income regions (n=20; HR, 0.95; 95% CI, 0.84-1.07). To determine whether regional variation is genuine, clinicians should evaluate the data according to the following 5 questions: (1) Are the regional groupings logical? (2) Is the regional difference on an absolute or relative scale? (3) Is the regional difference consistent and plausible? (4) Is the regional difference statistically significant? (5) Is there a clinical explanation? CONCLUSIONS: As registration studies in oncology become increasingly international, regional variations in trial outcomes may be detected. The question guide herein will help clinicians determine whether regional variations are likely to be clinically meaningful or statistical anomalies.

Trends in the use of short-course radiation therapy for rectal cancer in New South Wales, Australia.

INTRODUCTION: Trends in the use of short-course radiation therapy (RT) for rectal cancer in Australia are unknown. The purpose of this study was to compare short-course RT and long-course chemoradiation (CRT) utilisation in the neoadjuvant treatment of rectal cancer in New South Wales (NSW). METHODS: Patients who received neoadjuvant RT (2009-2014) for rectal cancer were identified from the NSW Central Cancer Registry. Univariate and multivariable analyses were performed to investigate factors associated with receipt of short-course RT. RESULTS: A total of 1196 (81%) patients received long-course CRT, and 274 (19%) patients received short-course RT. Receipt of short-course RT was associated with older age: 54% in patients ≥80 years, and 11% in patients <50 years (P < 0.0001). Patients with T2 disease (30%) were more likely to receive short-course RT, compared with T3 (19%) or T4 (8%) disease (P = 0.002). Patients with N0 (23%) disease were more likely to be treated with short-course RT, compared with N+ (16%) (P = 0.03). The proportion of short-course RT delivered to patients with Charlson Comorbidity Index (CCI) ≥ 2 (28%) was higher than patients with CCI = 0 (17%) (P = 0.002). There was wide variation in the proportion of short-course RT used across residence local health districts (5-29%) (P < 0.0001). CONCLUSION: In rectal cancer patients treated with neoadjuvant RT in NSW, 19% received short-course RT. The use of short-course RT was associated with older age, comorbidities and less advanced disease. Wide variation across NSW was identified and future research investigating factors for the variation will be useful.

Australia and New Zealand's responsibilities in improving oncology services in the Asia-Pacific: A call to action.

AIM: To review the expected increasing demand for cancer services among low and middle-income countries (LMICs) in the Asia-Pacific (APAC), and to describe ways in which Australia and New Zealand (ANZ) can provide support to improve cancer outcomes in our region. METHODS: We first review the current and projected incidence of cancer within the APAC between 2018 and 2040, and the estimated demand for chemotherapy, radiotherapy and surgery. We then explore potential ways in which ANZ can increase regional collaborations to improve cancer outcomes. RESULTS: We identify 6 ways that ANZ can collaborate with LMICs to improve cancer care in the APAC through the ANZ Regional Oncology Collaboration Strategy: Increasing education and institutional collaborations in the APAC region through in-country training, twinning partnerships, observerships and formalised training programs in order to increase cancer care quality and capacity. Promoting and assisting in the establishment and maintenance of population-based cancer registries in LMICs. Increasing research capacity in LMICs through collaboration and promoting high quality global oncology research within ANZ. Engaging and training Australian and New Zealand clinicians in global oncology, increasing awareness of this important career path, and increasing health policy engagement. Increasing web-based endeavours through virtual tumour boards, web-based advocacy platforms and web-based teaching programs. Continuing to leverage for funding through professional bodies, government, industry, not-for-profit organisations and local hospital funds. CONCLUSION: We propose the creation of an Australian and New Zealand Interest Group to provide formalised and sustained collaboration between researchers, clinicians and stakeholders.

Resource stratified guidelines for cancer: Are they all the same? Interguideline concordance for systemic treatment recommendations.

A number of organizations are producing resource stratified guidelines (RSGs) for cancer. Despite using similar definitions of resource levels, systemic treatment recommendations often differ between organizations. We systematically searched for RSGs focusing on solid tumors. We qualitatively compared the methods used to generate guidelines using the AGREE-II appraisal tool. We extracted systemic treatment recommendations and assessed interguideline concordance using the Gwet AC1 coefficient, stratified by resource level, treatment setting and cancer type. We identified 69 RSGs cancer covering 15 solid tumors produced by four organizations. Despite using common resource-level definitions (Basic, Core/Limited, Enhanced and Maximal), recommendations differed between organizations. Concordance for chemotherapy recommendations was poor in Basic (58.3%, Gwet 0.20), fair in Core (58.3%, Gwet 0.32) and excellent in Enhanced (92.4%, Gwet 0.92) and Maximal settings (95.4%, Gwet 0.95). Concordance rates for endocrine therapy were good in Basic (80% Gwet 0.61), and excellent in Core (90%, Gwet 0.87), Enhanced (90%, Gwet 0.89) and Maximal settings (90%, Gwet 0.89). There was moderate to excellent concordance in targeted therapy recommendations across all resource levels. Differences in recommendations appeared driven by different opinions among the chosen panel of experts regarding what is resource appropriate. Overall, we found that countries looking to base treatment and health-policy on RSGs will find conflicting information depending on which guidelines are used, particularly for chemotherapy in Basic and Core settings. Improved transparency regarding the methods used to determine the value of a therapy for a given resource level is needed.

Are NCCN Resource-Stratified Guidelines for Breast Cancer Systemic Therapy Achievable? A Population-Based Study of Global Need and Economic Impact.

PURPOSE: Resource-stratified guidelines (RSG) for cancer provide a hierarchy of interventions, based on resource availability. We quantify treatment need and cost if National Comprehensive Cancer Network (NCCN) RSGs for breast cancer (BC) are adopted globally. METHODS: We developed decision trees for first-course systemic therapy, merged with SEER and Global Cancer Observatory 2018 incidence data to estimate treatment need and cost if NCCN RSG are implemented globally based on country-level income. Simulations were used to quantify need and cost of globally scaling up services to Maximal. RESULTS: Based on NCCN RSG, first-course chemotherapy is indicated in 0% (Basic), 87% (Core), and 86% (Enhanced) but declined to 50% (Maximal) because of incorporation of genomic profiling. First-course endocrine therapy (ET) is indicated in 80% in all settings. In 2018, treatment need was 1.4 million people for chemotherapy, 183,943 for human epidermal growth factor receptor 2 (HER2) therapies and 1.6 million for ET. The cost per person for chemotherapy or HER2 or immunotherapy increased by 17-fold from Core to Maximal ($1,278-$22,313 Australian dollars [AUD]). The cost of ET per person rose eight-fold from Basic to Maximal ($1,236-$9,809 AUD). If all patients with BC globally were treated with Maximal resources, the need for chemotherapy would decline by 28%, whereas cost of first-course treatment would rise by 1.8-fold ($21-$37 billion AUD) because of more costly therapies. CONCLUSION: NCCN RSGs for BC could result in chemotherapy overtreatment in Core and Enhanced settings. The absence of chemotherapy in Basic settings should be reconsidered, and future iterations of RSG should perform cross-tumor comparisons to ensure equitable resource distribution and maximize population-level outcomes. Our model is flexible and can be tailored to the costs, population attributes, and resource availability of any institution or country for health-services planning.

Multi-parametric magnetic resonance imaging assessment of whole tumour heterogeneity for chemoradiotherapy response prediction in rectal cancer.

BACKGROUND AND PURPOSE: Prediction of chemoradiotherapy response (CRT) in locally advanced rectal cancer would enable stratification of management. The purpose was to prospectively evaluate multi-parametric magnetic resonance imaging (MRI) assessment of tumour heterogeneity combining diffusion weighted imaging (DWI) and dynamic contrast enhanced (DCE) MRI for the prediction of CRT response in locally advanced rectal cancer. MATERIALS AND METHODS: Patients with Stage II or III rectal adenocarcinoma undergoing neoadjuvant CRT and surgery underwent MRI (DWI and DCE) before, during (week 3), and after CRT (1 week before surgery). Patients with histopathology tumour regression grade (TRG) 0-1 were classified as responders, and TRG 2-3 were classified as non-responders. A whole tumour voxel-wise technique was used to produce apparent diffusion coefficient (ADC) and Ktrans (Tofts model) histograms derived from DWI and DCE-MRI, respectively. Logistic regression was used to predict response status for ADC and Ktrans quantiles. RESULTS: Thirty-three patients were included in this analysis; 16 responders, and 17 non-responders. On heterogeneity analysis, odds of being a responder were significantly higher after CRT (before surgery) for higher ADC 75th (p = 0.049) and ADC 90th (p = 0.034) percentile values. The Ktrans quantiles were lower in non-responders than responders before and during CRT, and higher after CRT although no significant association with response status was observed (p ≥ 0.10). CONCLUSIONS: DWI-MRI after CRT (before surgery) incorporating a histogram analysis of whole tumour heterogeneity was predictive of CRT response in patients with locally advanced rectal cancer. DCE-MRI did not add value in response prediction. CLINICAL TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR) number ACTRN12616001690448.

Patterns of care for men with prostate cancer: the 45 and Up Study.

OBJECTIVES: To describe patterns of care in New South Wales for men with prostate cancer, and to ascertain factors associated with receiving different types of treatment. DESIGN: Individual patient data record linkage study. SETTING, PARTICIPANTS: 4003 New South Wales men aged 45 years or more enrolled in the population-based 45 and Up Study in whom prostate cancer was first diagnosed during 2006-2013. MAIN OUTCOME MEASURES: Prostate cancer treatment type received; factors statistically associated with treatment received; proportions of patients who consulted radiation oncologists prior to treatment. RESULTS: In total, 1619 of 4003 patients underwent radical prostatectomy (40%), 893 external beam radiotherapy (EBRT) (22%), 183 brachytherapy (5%), 87 chemotherapy (2%), 373 androgen deprivation therapy alone (9%), and 848 no active treatment (21%). 205 of 1628 patients who had radical prostatectomies (13%) had radiation oncology consultations prior to surgery. Radical prostatectomy was more likely for patients aged 45-59 years, with regional stage disease, living 100 km or more from the nearest radiotherapy centre, having partners, or having private health insurance, while lower physical functioning, obesity, and living in areas of greater socio-economic disadvantage reduced the likelihood. EBRT was more likely for patients aged 70-79 years, with non-localised or unknown stage disease, living less than 100 km from the nearest radiotherapy centre, or not having private health insurance, while the likelihood was lower for patients aged 45-59 years or more than 80 years and for those who had several comorbid conditions. CONCLUSIONS: Men with prostate cancer were twice as likely to have radical prostatectomy as to receive EBRT, and fewer than one in seven had consulted radiation oncologists prior to prostatectomy. The treatment received was influenced by several socio-demographic factors. Given the treatment-specific side effects and costs, policies that affect access to different treatments for prostate cancer should be reviewed.

Radiotherapy service need in the Pacific Island countries.

BACKGROUND: Pacific Island Countries and Territories (PICTs) have experienced an increase in cancer burden in the recent years. There is need for major investments in the cancer treatment facilities including radiotherapy (RT). AIMS: This study aimed to provide a quantitative estimation of the effect of establishing new RT facilities on patient access through Geographic Information System (GIS) modelling of population density and service availability to assess the best location for a new RT centre when there are multiple competing locations. METHODS: Methods involved cancer epidemiological data collection and assessing RT demand (proportion needing RT) in 2040, assessment of current RT facilities meeting the demand, GIS-based assessment of minimal travel distance in relation to RT demand and scenario-based location planning with adoption of the principles of efficiency, availability and equity for establishment of suitability of new RT facilities. RESULTS: In 2040, three highest new cancer case projections are for Papua New Guinea (PNG) (22662), Fiji (2058) and New Caledonia (2037). Twenty-nine megavoltage machines (MVMs) are needed to meet adequate RT demand with three existing in New Caledonia, Guam and French Polynesia meeting 2-6% demand. PNG with highest RT demand of 68% and Fiji with second highest (6%) demand are found as the choice venues for maximum accessibility of cancer population within the PICTs. CONCLUSION: The travel distance-based GIS modelling estimation of establishment of new RT facilities will provide useful information for planning of RT services in the PICTS with improved patient outcome.

The value of first-line chemotherapy and targeted therapy in the treatment of breast cancer.

OBJECTIVE: To investigate the value (survival benefit and cost) of first-line chemotherapy and targeted therapy in breast cancer at a population level. METHODS: Based on guideline recommendations, a model of optimal utilisation was constructed for first-line chemotherapy and targeted therapy in breast cancer, calculating the survival benefit and average cost of all regimens recommended for each treatment indication at 5 years and at 10 years. RESULTS: Survival benefits from chemotherapy and targeted therapy differ markedly depending on the treatment indications. The cost per life-year gained at 5 years is $38,044 for stages I and II, $33,749 for stage III and $ 151,668 for patients presenting with stage IV breast cancer. The cost per life-year gained at 10 years is $ 13,587 for early breast cancer. The most expensive chemotherapy indication in breast cancer is the treatment of metastatic HER2-positive breast cancer costing $330,978 per LYG for a survival benefit of 11% at 5 years falling to zero survival benefit at 10 years. CONCLUSION: There are large differences in value between the different indications for first-course chemotherapy and targeted therapy in the treatment of breast cancer that should be considered when pricing cancer drugs.

Multicenter evaluation of MRI-based radiomic features: A phantom study.

INTRODUCTION: This work describes the development of a novel radiomics phantom designed for magnetic resonance imaging (MRI) that can be used in a multicenter setting. The purpose of this study is to assess the stability and reproducibility of MRI-based radiomic features using this phantom across different MRI scanners. METHODS & MATERIALS: A set of phantoms were three-dimensional (3D) printed using MRI visible materials. One set of phantoms were imaged on seven MRI scanners and one was imaged on one MRI scanner. Radiomics analysis of the phantoms, which included first-order features, shape and texture features was performed. Intraclass correlation coefficient (ICC) was used to assess the stability of radiomic features across eight scanners and the reproducibility of two printed models on one scanner. Coefficient of variation (COV) was used to assess the reproducibility of radiomics measurements in the phantom on a single scanner. RESULTS: The phantom models provide sufficient signal-to-noise and contrast in all the tumor models permitting robust automatic segmentation. During a 12-month period of monitoring, the phantom material was stable with T1 and T2 of 150.7 ± 6.7 ms and 56.1 ± 3.9 ms, respectively. Of all the radiomic features computed, 34 of 69 had COV < 10%. Features from first-order statistics were the most robust in stability across the eight scanners with eight of 12 (67%) having high stability. About 29 of 50 (58%) texture features had high stability and no shape features had high stability features across the eight scanners. CONCLUSION: A novel MRI radiomics phantom has been developed to assess the reproducibility and stability of MRI-based radiomic features across multiple institutions. The variation in radiomic feature stability demonstrates the need for caution when interpreting these features for clinical studies.

Quality management in radiation therapy: A 15 year review of incident reporting in two integrated cancer centres.

Fifteen years of reported incidents were reviewed to provide insight into the effectiveness of an Incident Learning System (ISL). The actual error rate over the 15 years was 1.3 reported errors per 1000 treatment attendances. Incidents were reviewed using a regression model. The average number of incidents per year and the number of incidents per thousand attendances declined over time. Two seven-year periods were considered for analysis and the average for the first period (2005-2011) was 6 reported incidents per 1000 attendances compared to 2 incidents for the later period (2012-2018), p < 0.05. SAC 1 and SAC 2 errors have reduced over time and the reduction could be attributed to the quality assurance aspect of IGRT where the incident is identified prior to treatment delivery rather than after, reducing the severity of any potential incidents. The reasoning behind overall reduction in incident reporting over time is unclear but may be associated to quality and technology initiatives, issues with the ISL itself or a change in the staff reporting culture.

Estimates of global chemotherapy demands and corresponding physician workforce requirements for 2018 and 2040: a population-based study.

BACKGROUND: The incidence of cancer (excluding non-melanomatous skin cancers) is projected to rise from 17·0 million to 26·0 million between 2018 and 2040. A large proportion of these patients would be likely to derive benefit from chemotherapy, but no studies so far have quantified current and projected global chemotherapy demands. We aimed to estimate changes in national, regional, and global demands for first-course chemotherapy and the cancer physician workforce between 2018 and 2040 if all patients were treated according to best-practice evidence-based guidelines. METHODS: Data for the incidence of 29 types of cancer in 183 countries in 2018, and projections of incidence in 2040, were obtained from GLOBOCAN 2018. Optimal chemotherapy utilisation from evidence-based guidelines was applied to these incidence data to generate the number of new patients requiring first-course chemotherapy in 2018 and 2040. We then estimated the corresponding cancer physician workforce required to deliver this chemotherapy (on the basis of physicians seeing 150 new patients requiring chemotherapy per year). We did sensitivity analyses to investigate how cancer stage at presentation affected chemotherapy demands. We also did sensitivity analyses to explore changes to workforce requirements if each physician was seeing 100 new patients requiring chemotherapy per year or 300 new patients requiring chemotherapy per year. FINDINGS: Between 2018 and 2040, the number of patients requiring first-course chemotherapy annually will increase from 9·8 million to 15·0 million, a relative increase of 53%. The estimated proportion of patients needing chemotherapy who reside in low-income or middle-income countries was 63% (6 162 240 of 9 782 783) in 2018, and will be 67% (10 071 049 of 14 984 560) in 2040. The most common indications for chemotherapy worldwide in 2040 will be lung cancer (accounting for 2 455 137 [16·4%] of 14 984 560 cases eligible for chemotherapy), breast cancer (1 898 740 [12·7%]), and colorectal cancer (1 678 153 [11·1%]). We estimated that, in 2018, 65 000 cancer physicians were required worldwide to deliver optimal chemotherapy-a figure that we estimate will rise to 100 000 by 2040 (with estimates ranging from from 50 000 to 150 000, depending on workload). INTERPRETATION: Strategic investments in chemotherapy service provision and cancer physicians are needed to meet the projected increased demand for chemotherapy in 2040. FUNDING: None.