Purpose: Pediatric patients with medulloblastoma in LMICs are most treated with 3D conformal phot... more Purpose: Pediatric patients with medulloblastoma in LMICs are most treated with 3D conformal photon craniospinal irradiation (CSI), a time-consuming, complex treatment to plan, especially in resource-constrained settings. Therefore, we developed and tested a 3D conformal CSI autoplanning tool for varying patient lengths. Methods and Materials: Autocontours were generated with a deep learning model trained:tested (80:20 ratio) on 143 pediatric medulloblastoma CT scans (patient ages, 2-19 years, median=7 years). Using the verified autocontours, the autoplanning tool generated 2 lateral brain fields matched to a single spine field, an extended single spine field, or 2 matched spine fields. Additional spine sub-fields were added to optimize the corresponding dose distribution. Feathering was implemented (yielding 9-12 fields) to give a composite plan. Each planning approach was tested on 6 patients (ages, 3-10 years). A pediatric radiation oncologist assessed clinical acceptability of e...
International Journal of Radiation Oncology*Biology*Physics, 2022
PURPOSE Randomized control trials (RCTs) are the cornerstone of delivering sustained improvements... more PURPOSE Randomized control trials (RCTs) are the cornerstone of delivering sustained improvements in cancer outcome. To inform radiotherapy research policy and prioritization, we analyze the radiotherapy RCT landscape including comparison with trials of systemic therapies over the same time period, with a specific focus on funding and disparities across income settings. METHODS AND MATERIALS This retrospective cohort study identified all phase three RCTs evaluating anticancer therapies published from 2014 to 2017. RCTs were classified according to anticancer modality and country of origin. Descriptive statistics were used to compare key characteristics of radiotherapy RCT studies according to study design characteristics, tumor types evaluated, types of intervention appraised, treatment intent and main funding sources. RESULTS The study cohort included 694 RCTs of which 64 were radiotherapy RCTs (9%) compared to 601 (87%) systemic therapy RCTs. 47% of all radiotherapy RCTs focused on two areas of evaluation; combining radiotherapy with systemic agents (25%) and changes in dose fractionation (22%). The most common cancers studied were head and neck (22%), lung (22%) and breast (14%) with cervical cancer trials only representing 3% of the cohort. 33% of radiotherapy RCTs met their primary end point. 62% of radiotherapy RCTs assessed interventions in the curative setting compared to 31% in systemic therapy RCTs. 77% of the radiotherapy RCTs were performed in high-income countries (HIC), 13% in low-and-middle-income countries (LMIC) and 11% in both HIC and LMICs. 17% of radiotherapy RCTs received funding from industry compared to 79% of systemic therapy RCTs. CONCLUSION This study has highlighted the need for greater investment in radiotherapy RCTs and the disparities in conduct of RCTs globally. The study emphases the urgent need for more capacity building for cancer clinical trials in LMICs and more sustainable funding sources.
Survival of Wilms tumor (WT) is >90% in high-resource settings but <30% in low-resource set... more Survival of Wilms tumor (WT) is >90% in high-resource settings but <30% in low-resource settings. Adapting a standardized surgical approach to WT is challenging in low-resource settings, but a local control strategy is crucial to improving outcomes. Objective: Provide resource-sensitive recommendations for the surgical management of WT. Methods: We performed a systematic review of PubMed and EMBASE through July 7, 2020, and used the GRADE approach to assess evidence and recommendations. Recommendations: Initiation of treatment should be expedited, and surgery should be done in a high-volume setting. Cross-sectional imaging should be done to optimize preoperative planning. For patients with typical clinical features of WT, biopsy should not be done before chemotherapy, and neoadjuvant chemotherapy should precede surgical resection. Also, resection should include a large transperitoneal laparotomy, adequate lymph node sampling, and documentation of staging findings. For WT with ...
Communicable diseases are still the leading cause of childhood mortality in third world countries... more Communicable diseases are still the leading cause of childhood mortality in third world countries. However, as prevention and treatment of malnutrition and infectious diseases improves, global health challenges are shifting towards combating non-communicable diseases including cancer which has high rates of mortality in children (Wilimas and Ribeiro 2001). More than two-thirds of the world’s pediatric cancers are currently diagnosed in low- and middle income countries (LMIC) (Kellie and Howard 2008). The patterns of occurrence of childhood cancer in LMIC compared to high income countries (HIC) and the lack of population-based cancer registries suggest that many patients die from undiagnosed cancer and the burden of childhood cancer is under-estimated. Children diagnosed with cancer in low-income countries (LIC) continue to have a much poorer chance of survival compared to those in HIC (Fig. 21.1).
Radiosurgery is a recognized safe form of treating and usually curing arteriovenous malformations... more Radiosurgery is a recognized safe form of treating and usually curing arteriovenous malformations (AVMs). Complications related to radiosurgery, especially late sequelae, are rare. Such sequelae may be secondary to incomplete treatment of the original lesion such as haemorrhage, or secondary to the radiation damage to the tissue, or both. Sometimes treatment may induce new lesions. We report a patient who had an AVM cured with radiosurgery, but developed hemisensory loss acutely and had changes on MRI in keeping with a haematoma. We discuss the possible differential diagnosis that should be considered.
We define rare tumors in pediatric oncology arbitrarily as including the following histologies: r... more We define rare tumors in pediatric oncology arbitrarily as including the following histologies: retinoblastoma, nasopharyngeal carcinoma, desmoid, non-CNS germ cell tumors, liver tumors, pleuropulmonary blastoma (PPB), chordoma, malignant peripheral nerve sheath tumors, and for some the true connective tissue tumors. Relative to adult tumors, practically every tumor in this text could be considered rare but these histologies are rare even within the scope of pediatric care.
Prolactinomas in childhood and adolescence are rare. However, in male patients in particular they... more Prolactinomas in childhood and adolescence are rare. However, in male patients in particular they may become extremely large and invasive, resulting in visual impairment without necessarily producing endocrine symptoms. We report on two adolescent males who presented with deteriorating vision over a long period of time and who had optic atrophy on examination. Magnetic resonance imaging identified tumours with extensive anterior skull base invasion and suprasellar extension. Prolactin levels in both patients were markedly elevated, and a diagnosis of prolactinoma was made. Bromocriptine treatment was started resulting in lowered prolactin levels, improved vision and tumour shrinkage on imaging. A male child or adolescent presenting with diminished vision and found to have suprasellar or anterior skull base tumour should have their prolactin levels checked to rule out a prolactinoma, which can be successfully managed with medical therapy.
Eighty-five percent of the world’s children live in areas of limited resources. The poorest conti... more Eighty-five percent of the world’s children live in areas of limited resources. The poorest continent, Africa, accounts for 23% of pediatric disease but only employs 1.3% of the world’s health workers. Pediatric neuro-oncology requires highly specialized teams, and in countries where there are inadequate resources for even the most common diseases, such as infections, malnutrition, and HIV-related disease, it is understandable that children with central nervous system (CNS) tumors are not a priority.
Introduction It is estimated that South Africa (SA) will require 56 additional linear accelerator... more Introduction It is estimated that South Africa (SA) will require 56 additional linear accelerators by 2020. Linacs are considered a scarce resource and optimal use is essential. Many state run facilities in SA make use of historic staffing models, not taking into account changes in techniques or alternative work practices. Attempts to implement alternative staffing models can result in resistance as staff struggle to link work practice with patient numbers. A visual tool was developed to assist staff in assessing alternative practices and linking the staffing models to the number of patients treated. Materials and Methods A magnetic game board called the GSH Time Machine was developed in the form of a 12 hour “clock face”, allowing visualisation of staffing activities on the inside of the clock face, linked to the treatment slots utilised on the outside of the clock face. A workshop was held with Radiotherapy staff members to develop different staffing boards. Each team was allowed ...
PURPOSE Radiation treatment planning for head and neck cancer is a complex process with much vari... more PURPOSE Radiation treatment planning for head and neck cancer is a complex process with much variability; automated treatment planning is a promising option to improve plan quality and efficiency. This study compared radiation plans generated from a fully automated radiation treatment planning system to plans generated manually that had been clinically approved and delivered. METHODS AND MATERIALS The study cohort consisted of 50 patients treated by a specialized head and neck cancer team at a tertiary care center. An automated radiation treatment planning system, the Radiation Planning Assistant, was used to create autoplans for all patients using their original, approved contours. Common dose-volume histogram (DVH) criteria were used to compare the quality of autoplans to the clinical plans. Fourteen radiation oncologists, each from a different institution, then reviewed and compared the autoplans and clinical plans in a blinded fashion. RESULTS Autoplans and clinical plans were v...
Purpose: Pediatric patients with medulloblastoma in LMICs are most treated with 3D conformal phot... more Purpose: Pediatric patients with medulloblastoma in LMICs are most treated with 3D conformal photon craniospinal irradiation (CSI), a time-consuming, complex treatment to plan, especially in resource-constrained settings. Therefore, we developed and tested a 3D conformal CSI autoplanning tool for varying patient lengths. Methods and Materials: Autocontours were generated with a deep learning model trained:tested (80:20 ratio) on 143 pediatric medulloblastoma CT scans (patient ages, 2-19 years, median=7 years). Using the verified autocontours, the autoplanning tool generated 2 lateral brain fields matched to a single spine field, an extended single spine field, or 2 matched spine fields. Additional spine sub-fields were added to optimize the corresponding dose distribution. Feathering was implemented (yielding 9-12 fields) to give a composite plan. Each planning approach was tested on 6 patients (ages, 3-10 years). A pediatric radiation oncologist assessed clinical acceptability of e...
International Journal of Radiation Oncology*Biology*Physics, 2022
PURPOSE Randomized control trials (RCTs) are the cornerstone of delivering sustained improvements... more PURPOSE Randomized control trials (RCTs) are the cornerstone of delivering sustained improvements in cancer outcome. To inform radiotherapy research policy and prioritization, we analyze the radiotherapy RCT landscape including comparison with trials of systemic therapies over the same time period, with a specific focus on funding and disparities across income settings. METHODS AND MATERIALS This retrospective cohort study identified all phase three RCTs evaluating anticancer therapies published from 2014 to 2017. RCTs were classified according to anticancer modality and country of origin. Descriptive statistics were used to compare key characteristics of radiotherapy RCT studies according to study design characteristics, tumor types evaluated, types of intervention appraised, treatment intent and main funding sources. RESULTS The study cohort included 694 RCTs of which 64 were radiotherapy RCTs (9%) compared to 601 (87%) systemic therapy RCTs. 47% of all radiotherapy RCTs focused on two areas of evaluation; combining radiotherapy with systemic agents (25%) and changes in dose fractionation (22%). The most common cancers studied were head and neck (22%), lung (22%) and breast (14%) with cervical cancer trials only representing 3% of the cohort. 33% of radiotherapy RCTs met their primary end point. 62% of radiotherapy RCTs assessed interventions in the curative setting compared to 31% in systemic therapy RCTs. 77% of the radiotherapy RCTs were performed in high-income countries (HIC), 13% in low-and-middle-income countries (LMIC) and 11% in both HIC and LMICs. 17% of radiotherapy RCTs received funding from industry compared to 79% of systemic therapy RCTs. CONCLUSION This study has highlighted the need for greater investment in radiotherapy RCTs and the disparities in conduct of RCTs globally. The study emphases the urgent need for more capacity building for cancer clinical trials in LMICs and more sustainable funding sources.
Survival of Wilms tumor (WT) is >90% in high-resource settings but <30% in low-resource set... more Survival of Wilms tumor (WT) is >90% in high-resource settings but <30% in low-resource settings. Adapting a standardized surgical approach to WT is challenging in low-resource settings, but a local control strategy is crucial to improving outcomes. Objective: Provide resource-sensitive recommendations for the surgical management of WT. Methods: We performed a systematic review of PubMed and EMBASE through July 7, 2020, and used the GRADE approach to assess evidence and recommendations. Recommendations: Initiation of treatment should be expedited, and surgery should be done in a high-volume setting. Cross-sectional imaging should be done to optimize preoperative planning. For patients with typical clinical features of WT, biopsy should not be done before chemotherapy, and neoadjuvant chemotherapy should precede surgical resection. Also, resection should include a large transperitoneal laparotomy, adequate lymph node sampling, and documentation of staging findings. For WT with ...
Communicable diseases are still the leading cause of childhood mortality in third world countries... more Communicable diseases are still the leading cause of childhood mortality in third world countries. However, as prevention and treatment of malnutrition and infectious diseases improves, global health challenges are shifting towards combating non-communicable diseases including cancer which has high rates of mortality in children (Wilimas and Ribeiro 2001). More than two-thirds of the world’s pediatric cancers are currently diagnosed in low- and middle income countries (LMIC) (Kellie and Howard 2008). The patterns of occurrence of childhood cancer in LMIC compared to high income countries (HIC) and the lack of population-based cancer registries suggest that many patients die from undiagnosed cancer and the burden of childhood cancer is under-estimated. Children diagnosed with cancer in low-income countries (LIC) continue to have a much poorer chance of survival compared to those in HIC (Fig. 21.1).
Radiosurgery is a recognized safe form of treating and usually curing arteriovenous malformations... more Radiosurgery is a recognized safe form of treating and usually curing arteriovenous malformations (AVMs). Complications related to radiosurgery, especially late sequelae, are rare. Such sequelae may be secondary to incomplete treatment of the original lesion such as haemorrhage, or secondary to the radiation damage to the tissue, or both. Sometimes treatment may induce new lesions. We report a patient who had an AVM cured with radiosurgery, but developed hemisensory loss acutely and had changes on MRI in keeping with a haematoma. We discuss the possible differential diagnosis that should be considered.
We define rare tumors in pediatric oncology arbitrarily as including the following histologies: r... more We define rare tumors in pediatric oncology arbitrarily as including the following histologies: retinoblastoma, nasopharyngeal carcinoma, desmoid, non-CNS germ cell tumors, liver tumors, pleuropulmonary blastoma (PPB), chordoma, malignant peripheral nerve sheath tumors, and for some the true connective tissue tumors. Relative to adult tumors, practically every tumor in this text could be considered rare but these histologies are rare even within the scope of pediatric care.
Prolactinomas in childhood and adolescence are rare. However, in male patients in particular they... more Prolactinomas in childhood and adolescence are rare. However, in male patients in particular they may become extremely large and invasive, resulting in visual impairment without necessarily producing endocrine symptoms. We report on two adolescent males who presented with deteriorating vision over a long period of time and who had optic atrophy on examination. Magnetic resonance imaging identified tumours with extensive anterior skull base invasion and suprasellar extension. Prolactin levels in both patients were markedly elevated, and a diagnosis of prolactinoma was made. Bromocriptine treatment was started resulting in lowered prolactin levels, improved vision and tumour shrinkage on imaging. A male child or adolescent presenting with diminished vision and found to have suprasellar or anterior skull base tumour should have their prolactin levels checked to rule out a prolactinoma, which can be successfully managed with medical therapy.
Eighty-five percent of the world’s children live in areas of limited resources. The poorest conti... more Eighty-five percent of the world’s children live in areas of limited resources. The poorest continent, Africa, accounts for 23% of pediatric disease but only employs 1.3% of the world’s health workers. Pediatric neuro-oncology requires highly specialized teams, and in countries where there are inadequate resources for even the most common diseases, such as infections, malnutrition, and HIV-related disease, it is understandable that children with central nervous system (CNS) tumors are not a priority.
Introduction It is estimated that South Africa (SA) will require 56 additional linear accelerator... more Introduction It is estimated that South Africa (SA) will require 56 additional linear accelerators by 2020. Linacs are considered a scarce resource and optimal use is essential. Many state run facilities in SA make use of historic staffing models, not taking into account changes in techniques or alternative work practices. Attempts to implement alternative staffing models can result in resistance as staff struggle to link work practice with patient numbers. A visual tool was developed to assist staff in assessing alternative practices and linking the staffing models to the number of patients treated. Materials and Methods A magnetic game board called the GSH Time Machine was developed in the form of a 12 hour “clock face”, allowing visualisation of staffing activities on the inside of the clock face, linked to the treatment slots utilised on the outside of the clock face. A workshop was held with Radiotherapy staff members to develop different staffing boards. Each team was allowed ...
PURPOSE Radiation treatment planning for head and neck cancer is a complex process with much vari... more PURPOSE Radiation treatment planning for head and neck cancer is a complex process with much variability; automated treatment planning is a promising option to improve plan quality and efficiency. This study compared radiation plans generated from a fully automated radiation treatment planning system to plans generated manually that had been clinically approved and delivered. METHODS AND MATERIALS The study cohort consisted of 50 patients treated by a specialized head and neck cancer team at a tertiary care center. An automated radiation treatment planning system, the Radiation Planning Assistant, was used to create autoplans for all patients using their original, approved contours. Common dose-volume histogram (DVH) criteria were used to compare the quality of autoplans to the clinical plans. Fourteen radiation oncologists, each from a different institution, then reviewed and compared the autoplans and clinical plans in a blinded fashion. RESULTS Autoplans and clinical plans were v...
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