Research Articles (Radiation Oncology)

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    The silent pandemic in South Africa : extra-pulmonary tuberculosis from head to heel
    (AOSIS, 2021-04) Le Roux, Camilla E.; Vlok, Sucari S. C.
    Extra-pulmonary tuberculosis (EPTB), caused by Mycobacterium tuberculosis, is the leading cause of communicable disease-related deaths in people with human immunodeficiency virus (HIV) worldwide and in South Africa. Mycobacterium tuberculosis disseminates haematogenously from an active primary lung focus and may affect extra-pulmonary sites in up to 15% of patients. Extra-pulmonary TB may present with a normal chest radiograph, which often causes a significant diagnostic dilemma. This review describes the main sites of involvement in EPTB, which is illustrated by local imaging examples.
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    Automated radiation treatment planning for cervical cancer
    (Elsevier, 2020-10) Rhee, Dong Joo; Jhingran, Anuja; Kisling, Kelly; Cardenas, Carlos; Simonds, Hannah; Court, Laurence
    The radiation treatment-planning process includes contouring, planning, and reviewing the final plan, and each component requires substantial time and effort from multiple experts. Automation of treatment planning can save time and reduce the cost of radiation treatment, and potentially provides more consistent and better quality plans. With the recent breakthroughs in computer hardware and artificial intelligence technology, automation methods for radiation treatment planning have achieved a clinically acceptable level of performance in general. At the same time, the automation process should be developed and evaluated independently for different disease sites and treatment techniques as they are unique from each other. In this article, we will discuss the current status of automated radiation treatment planning for cervical cancer for simple and complex plans and corresponding automated quality assurance methods. Furthermore, we will introduce Radiation Planning Assistant, a web-based system designed to fully automate treatment planning for cervical cancer and other treatment sites.
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    Fully automatic treatment planning for external-beam radiation therapy of locally advanced cervical cancer : a tool for low-resource clinics
    (American Society of Clinical Oncology, 2019) Kisling, Kelly; Zhang, Lifei; Simonds, Hannah M.; Fakie, Nazia; Yang, Jinzhong; McCarroll, Rachel; Balter, Peter; Burger, Hester; Bogler, Oliver; Howell, Rebecca; Schmeler, Kathleen; Mejia, Mike; Beadle, Beth M.; Jhingran, Anuja; Court, Laurence
    PURPOSE: The purpose of this study was to validate a fully automatic treatment planning system for conventional radiotherapy of cervical cancer. This system was developed to mitigate staff shortages in low-resource clinics. METHODS: In collaboration with hospitals in South Africa and the United States, we have developed the Radiation Planning Assistant (RPA), which includes algorithms for automating every step of planning: delineating the body contour, detecting the marked isocenter, designing the treatment-beam apertures, and optimizing the beam weights to minimize dose heterogeneity. First, we validated the RPA retrospectively on 150 planning computed tomography (CT) scans. We then tested it remotely on 14 planning CT scans at two South African hospitals. Finally, automatically planned treatment beams were clinically deployed at our institution. RESULTS: The automatically and manually delineated body contours agreed well (median mean surface dis- tance, 0.6 mm; range, 0.4 to 1.9 mm). The automatically and manually detected marked isocenters agreed well (mean difference, 1.1 mm; range, 0.1 to 2.9 mm). In validating the automatically designed beam apertures, two physicians, one from our institution and one from a South African partner institution, rated 91% and 88% of plans acceptable for treatment, respectively. The use of automatically optimized beam weights reduced the maximum dose significantly (median, −1.9%; P , .001). Of the 14 plans from South Africa, 100% were rated clinically acceptable. Automatically planned treatment beams have been used for 24 patients with cervical cancer by physicians at our institution, with edits as needed, and its use is ongoing. CONCLUSION: We found that fully automatic treatment planning is effective for cervical cancer radiotherapy and may provide a reliable option for low-resource clinics. Prospective studies are ongoing in the United States and are planned with partner clinics.
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    The utility of PET-CT in the staging and management of advanced and recurrent malignant melanoma
    (Medpharm Publications, 2019) Twycross, S. H.; Burger, Henriette; Holness, Jen L.
    BACKGROUND: Accurate pre-operative staging and correct surgical selection of patients with malignant melanoma reduces unnecessary morbidity and mortality, improves distant control and may improve survival. 18F-fluorodeoxyglucose Positron Emission Tomography Computed Tomography (18F-FDG PET-CT) has been shown to be useful in exclusion of metastatic sites and aids in surgical planning in stage III and potentially resectable stage IV disease. The primary objective of the study was to determine whether the use of PET-CT alters the initial staging and management of patients with advanced and recurrent melanoma METHODS: Retrospective analysis of clinical records of patients with malignant melanoma referred for staging PET-CT over a three-year period at our institution was performed. Pre- and post-PET-CT stage was recorded and a descriptive analysis was done to determine whether PET-CT resulted in a change in stage grouping and whether this change effected a change in clinical management RESULTS: A change in stage grouping occurred in 21/39 (53.8%) of patients, 76.2% of which were up-staged and 23.8% down staged. On analysis of stage III/Iv and recurrent melanoma, a change in stage occurred in 90% of stage III, 50% of stage IV and 50% of recurrent melanoma patients. This effected a change in management in 86.7% of patients with stage III, IV and recurrent melanoma collectively CONCLUSION: PET-CT is a useful tool in the staging and subsequent management of melanoma. Its utility is pronounced in advanced and recurrent melanoma
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    Managing gestational trophoblastic neoplasm (GTN) and people living with HIV (PLWH)
    (MedPharm Publications, 2019) Barnardt, Pieter
    The 2017 World Health Organization (WHO) global report on HIV/AIDS estimated that sub-Saharan Africa comprised 64% of the global HIV burden, with a current estimate of 19.4 million cases in Eastern and Southern Africa. Since the introduction of antiretroviral therapy (ART) there has been a 30–40% increase in the incidence of non-AIDS malignancies. Gestational trophoblastic disease comprises of a spectrum of pregnancy-related disorders with an overall cure rate of 90%. The response to treatment is generally favourable but the associated complications of HIV, comorbidities, poor performance status and extent of metastatic disease in gestational trophoblastic neoplasm patients receiving chemotherapy, compromises the outcome and survival.