Browsing by Author "Van Zyl, Anel"

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    Late effects of childhood cancer and – treatment in a South African cohort
    (Stellenbosch : Stellenbosch University, 2023-03) Van Zyl, Anel; Kruger, Mariana; Rogers, Paul C; Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Paediatrics and Child Health.
    ENGLISH ABSTRACT: Survival rates for childhood cancer have increased dramatically over the last few decades. Unfortunately, cure for childhood cancer survivors (CCSs) often comes at a cost. Most CCSs will develop at least one late effect or complication of the previous cancer or its treatment, potentially negatively impacting their health-related quality of life (HRQoL). Therefore, long-term follow-up (LTFU) care is necessary after treatment completion. LTFU care is established in most high-income countries (HICs) but is inadequate in most low- and middle-income countries (LMICs) due to limited resources. Little information on LTFU care for CCSs in South Africa is available, and no structured national LTFU programme exists. This dissertation aimed to investigate global and local LTFU care models and practices, document physical and psychological late effects in a South African CCS cohort, determine their HRQoL, describe their healthcare engagement patterns, and ultimately propose an appropriate LTFU care model for South Africa. A scoping review of LTFU care delivery in HICs and LMICs found that the most commonly used LTFU care model in LMICs was the cancer-centre-based model (the cancer centre provided all LTFU services). (Chapter 2) The community-based and shared care models (care divided between the cancer centre and healthcare partners at secondary or primary healthcare institutions or general practitioners) were increasingly used. A survivorship care plan was crucial for the success of a shared care model. Barriers to LTFU care in LMICs included a lack of trained staff and time, transport problems, insufficient funding, a lack of awareness concerning late effects among CCSs, and inadequate transitioning of care. In some LMICs, non-profit organisations provided funding for LTFU clinics and transportation. A risk-based LTFU stratification model where CCSs with a higher risk for late effects attended the cancer centre annually and those with a lower risk attended a community centre less frequently lessened the burden on the healthcare systems with increased adherence. A shared care, risk stratified LTFU programme with local LTFU guidelines would suit the South African healthcare system and environment. Subsequently, we surveyed local paediatric oncologists’ perceived knowledge regarding LTFU care and the current status of local LTFU care. (Chapter 3) Almost all participants regarded LTFU care and a national LTFU programme as important. However, this research highlighted inadequacies in the LTFU care for CCSs in South Africa, including a lack of formal training in and knowledge of LTFU care, as well as inadequate communication about potential late effects with CCSs. Only half of the paediatric oncologists used LTFU guidelines, and most adjusted them due to service constraints. Paediatric oncologists provided most of the LTFU care, while almost half successfully practiced a shared care model. The research confirmed the need for local LTFU guidelines to guide paediatric oncologists and other healthcare providers in the provision of LTFU care to CCS. We conducted a prospective cross-sectional analytic study to document all late effects in a CCS cohort at Tygerberg Hospital. (Chapter 4) One hundred and sixty CCSs attended a physical LTFU assessment and had appropriate surveillance special investigations. A higher proportion (91.3%) of CCSs compared to similar publications had at least one late effect. Most late effects were mild to moderate in severity. Common late effects were gastrointestinal, metabolic, haematological, musculoskeletal, and neurological disorders. Significant risk factors for late effects included cancer diagnosis, chemotherapy intensity, and radiotherapy. The cohort exhibited poor school performance, while their nutritional and socio-economic status worsened from diagnosis to study visit. This study confirmed a high prevalence of late effects among this South African cohort of CCSs. The worsening socio-economic circumstances might influence adherence to LTFU care. A formal LTFU programme will improve the early identification of and intervention for late effects in South African CCSs, which can improve outcomes. We investigated the level of psychological distress in adult CCSs. (Chapter 5) Forty participants completed the Brief Symptom Inventory-18 instrument for self-reported symptoms. We compared results utilising different case rules (Global Severity Index (GSI) T scores of ≥ 50, ≥ 57, and ≥ 63) for the identification of psychological distress. A GSI T score of ≥ 63 identified only 10% of survivors with psychological distress; a GSI T score of ≥ 57 identified 32.5%, and a GSI T score of ≥ 50 identified 45%. Significant risk factors were radiotherapy, the presence of more than six late effects, the severity of late effects, and a follow-up period of 11-20 years. The study revealed higher levels of psychological distress for this cohort utilising the GSI T score ≥ 50 and ≥ 57 case rules than reported in the literature. It underscored the importance of formal screening for psychological distress via a recognised instrument during LTFU. We also performed a pilot study to investigate a South African CCS cohort's HRQoL. (Chapter 6) CCSs, at least five years after diagnosis, completed the Minneapolis-Manchester Quality of Life adolescent- and adult forms. The age at the study visit and the number and severity of late effects were significantly associated with a poor overall HRQoL. Female sex was a risk factor for poorer psychological functioning. Compared to the adolescent-form cohort, the adult-form cohort had poorer psychological and social functioning and a more inferior body image. One lower stratum of socio-economic status was significantly associated with a more inferior body image and outlook on life. This study identified specific subsets of CCSs that have poor HRQoL. CCSs should be screened for HRQoL to ensure those needing psychological support can access such interventions. The last research component was a linkage analysis study to investigate the healthcare engagement patterns, late effects, and chronic diseases of the CCSs who could not attend physical LTFU assessments or were not contactable. (Chapter 7) These CCSs mainly attended tertiary- and primary-level institutions. A diagnosis at under four years of age, female sex, a cancer diagnosis of leukaemia, treatment with chemotherapy only, and a follow-up period of 16-25 years were associated with the highest number of healthcare visits. The most documented healthcare problems were infections and haematological, neurological, gastrointestinal, dermatological, and endocrinological abnormalities. Brain tumour survivors had the highest risk for healthcare visits at tertiary-level institutions and clinical abnormalities. Older survivors visited healthcare institutions more often. However, as the follow-up period increased, the healthcare visits decreased. This research provided valuable data about the healthcare use patterns of local CCSs. It highlighted the importance of strategies to retain CCSs in LTFU care. This dissertation provided novel and crucial data about the late effects of a CCS cohort in South Africa. We suggest implementing a risk-based shared care national LTFU programme with local LTFU guidelines to ensure sustainable and equitable LTFU care for all CCSs in South Africa. (Chapter 8). The provision of a survivorship care plan and adequate transitioning of healthcare is essential for success. A novel score-based LTFU risk stratification model that incorporates the number and severity of late effects, as well as the level of psychological distress and HRQoL, will facilitate a holistic approach to LTFU care and more accurate identification of CCSs.
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    Nephroblastoma - a 25 year review of a South African unit
    (PubMed Central, 2014-09-15) Visser, Yolandi Thelma; Uys, Ronelle; Van Zyl, Anel; Stefan, Daniela Cristina
    Rationale: To determine the outcome of patients with nephroblastoma in a South African hospital. Objective: To determine if there is a difference in the outcome of patients with nephroblastoma comparing two treatment protocols SIOP (Société International D’Oncologie Pédiatrique Protocol) versus NWTS (National Wilms’ Tumour Study Protocol). Methods and results: A retrospective audit of 25 years (1983-2007), of children diagnosed with nephroblastoma in Tygerberg Hospital. One hundred and seven patients were included in the study and 98 were analyzed. The average age at diagnosis was 3.8 years. Most patients (37%) presented with stage 1 of the disease, followed by patients with stage 3 (27%). Most patients were treated according to the SIOP protocol (61%). Gender and race did not influence the outcome. Patients with stage 1 and 2 of the disease had the best outcome (76% versus 43% for stages 3 and 4). The SIOP group had a better outcome than the NWTS group (p value 0.001). The two groups had an equal distribution of the stage of presentation. The tumor volumes were bigger in the NWTS group (1004cm3 compared to 613cm3). Nutritional status did not influence the outcome although more patients were underweight for age in the SIOP group. The statistical methods used were: Kaplan Meier, Gehan’s Wilcoxon Test, Chi –square test and the Fisher exact test.