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Tamoxifen is the most used hormonal therapy for oestrogen receptor-positive breast cancer. CYP2D6 is the main enzyme in the metabolic pathway of tamoxifen to endoxifen. Variations in endoxifen plasma concentrations are associated with CYP2D6 polymorphisms. This study aimed to determine the association between the CYP2D6 polymorphisms and endoxifen plasma concentrations in a cohort of Zimbabwean breast cancer patients (n = 40). TaqMan genotyping and copy number assays were done to determine CYP2D6 genotypes. Tamoxifen and metabolites were quantitated using LC-MS/MS. The population had high frequencies of the CYP2D6 reduced function alleles, *17 (15%) and *29 (18%). The median endoxifen concentration was 4.78 ng/mL, and in 55% of the patients, mostly intermediate metabolizers were below the endoxifen therapeutic threshold of 5.97 ng/mL. The CYP2D6 phenotypes and activity scores were significantly associated with endoxifen plasma concentrations (P = 0.0151) and with endoxifen to N-desmethyl-tamoxifen ratios (P = 0.0006).
Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Farmacogenética , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Cromatografia Líquida , Zimbábue , Antineoplásicos Hormonais/uso terapêutico , Antineoplásicos Hormonais/farmacocinética , Espectrometria de Massas em Tandem , Tamoxifeno/uso terapêutico , Tamoxifeno/farmacocinética , GenótipoRESUMO
BACKGROUND: Cervical cancer treatment and care remains limited in Zimbabwe despite the growing burden of the disease among women. This study was aimed at investigating strategies to address barriers in accessing treatment and care by women with cervical cancer in Harare, Zimbabwe. METHODS: A qualitative inquiry was conducted to generate evidence for this study. Eighty-four (84) participants were purposively selected for interviews and participation in focus group discussions. The participants were selected from cervical cancer patients, caregivers of cervical cancer patients, health workers involved in the care of cervical cancer patients as well as relevant policy makers in the Ministry of Health and Child Care. Participants were selected in such as a way as to ensure different of characteristics to obtain diverse perspectives about the issues under study. Discussion and interview guides were used as data collection tools and discussions/interviews were audio-recorded, transcribed and translated into English. Inductive thematic analysis was conducted using Dedoose software. RESULTS: Salient sub-themes that emerged in the study at the individual patient level were: provision of free or subsidized services, provision of transport to treating health facilities and provision of accommodation to patients undergoing treatment. At the societal level, the sub-themes were: strengthening of health education in communities and training of health workers and community engagement. Salient sub-themes from the national health system level were: establishment of more screening and treatment health facilities, increasing the capacities of existing facilities, decentralization of some services, building of multidisciplinary teams of health workers, development and rolling out of standardized guidelines and reformation of Acquired Immunodeficiency Virus (AIDS) levy into a fund that would finance priority disease areas. CONCLUSION: This study revealed some noteworthy strategies to improve access to cervical cancer treatment and care in low-income settings. Improved domestic investments in health systems and reforming health policies underpinned on strong political are recommended.
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Cuidados Paliativos , Neoplasias do Colo do Útero , Criança , Feminino , Grupos Focais , Acessibilidade aos Serviços de Saúde , Humanos , Saúde Pública , Pesquisa Qualitativa , Neoplasias do Colo do Útero/terapia , ZimbábueRESUMO
PURPOSE: Hypofractionated breast radiotherapy has been found to be equivalent to conventional fractionation in many clinical trials. Using data from the European Society for Radiotherapy and Oncology Global Impact of Radiotherapy in Oncology survey, we identified preferences for hypofractionation in breast cancer across World Bank income groups and the perceived facilitators and barriers to its use. MATERIALS AND METHODS: An international, electronic survey was administered to radiation oncologists from 2018 to 2019. Demographics, practice characteristics, preferred hypofractionation regimen for specific breast cancer scenarios, and facilitators and barriers to hypofractionation were reported and stratified by World Bank income groups. Variables associated with hypofractionation were assessed using multivariate logistic regression models. RESULTS: One thousand four hundred thirty-four physicians responded: 890 (62%) from high-income countries (HICs), 361 (25%) from upper-middle-income countries (UMICs), 183 (13%) from low- and lower-middle-income countries (LLMICs). Hypofractionation was preferred most frequently in node-negative disease after breast-conserving surgery, with the strongest preference reported in HICs (78% from HICs, 54% from UMICs, and 51% from LLMICs, P < .001). Hypofractionation for node-positive disease postmastectomy was more frequently preferred in LLMICs (28% from HICs, 15% from UMICs, and 35% from LLMICs, P < .001). Curative doses of 2.1 to < 2.5 Gy in 15-16 fractions were most frequently reported, with limited preference for ultra-hypofractionation, but significant variability in palliative dosing. In adjusted analyses, UMICs were significantly less likely than LLMICs to prefer hypofractionation across all curative clinical scenarios, whereas respondents with > 1 million population catchments and with intensity-modulated radiotherapy were more likely to prefer hypofractionation. The most frequently cited facilitators and barriers were published evidence and fear of late toxicity, respectively. CONCLUSION: Preference for hypofractionation varied for curative indications, with greater acceptance in earlier-stage disease in HICs and in later-stage disease in LLMICs. Targeted educational interventions and greater inclusivity in radiation oncology clinical trials may support greater uptake.
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Neoplasias da Mama , Hipofracionamento da Dose de Radiação , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Mastectomia , Fracionamento da Dose de Radiação , Inquéritos e QuestionáriosRESUMO
As the burden of cancer increases worldwide, more so in low- and middle-income countries, one of the greatest challenges is human resource capacity development. Addressing this is critical in reducing the burden of cancer in the African continent. Other challenges include socio-economic demographics and disparities in the overall cancer care. Lack of sufficient numbers of qualified staff has been one of the obstacles in developing adequate and modern cancer treatment centres in Africa. Training in clinical oncology in Zimbabwe was established in 1990 through the collaboration between the Government of Zimbabwe and the WHO as a regional project. The training is offered by the University of Zimbabwe through the established Master of Medicine in Radiotherapy and Oncology (MMed Rad & Onco) postgraduate programme. Regional and local fellows have been trained, yielding more than 20 clinical oncologists over the years, who have initiated cancer treatment facilities in Africa and beyond. They have continued to train others, fulfilling the original WHO programme target of transfer of skills in sub-Saharan Africa. Collaborations with external partners have complemented efforts by the local faculty in addressing deficiencies in training, in areas where experts in the subject are lacking and in supporting nationals working abroad to come and teach newer technologies and techniques. The curriculum continues to evolve from knowledge-based training to competency-based training. However, there is a need to expand the current infrastructure to keep up with changing technology. Clinical oncology training in Zimbabwe continues and remains a regional resource. Emphasis on subspecialising seems to be the next natural step in progression. Strengthening of other disciplines, including surgical oncology and medical physics, would be complementary to the training. The programme is an example of a sustainable initiative born out of collaborative partnership and is sustained by local resources. The greater majority of qualified oncologists have remained in Africa.
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BACKGROUND: Breast cancer is the second most common cancer among women in Zimbabwe. Patients face socioeconomic barriers to accessing oncology care, including radiotherapy. We sought to understand patterns of care and adherence for women with breast cancer in sub-Saharan Africa (SSA) with radiotherapy access. METHODS: A retrospective cohort was created for women with breast cancer evaluated at the Parirenyatwa Hospital Radiotherapy and Oncology Center (RTC) from 2014 to 2018. Clinical data were collected to define patterns of care. Non-adherence was modeled as a binary outcome with different criteria for patients with localized versus metastatic disease. RESULTS: In total, 351 women presented with breast cancer with median age 51 at diagnosis (IQR: 43-61). Receptor status was missing for 71% (248). 199 (57%) had non-metastatic disease, and 152 (43%) had metastases. Of women with localized disease, 34% received post-mastectomy radiation. Of women with metastatic disease, 9.7% received radiotherapy. Metastatic disease and missing HIV status were associated with increased odds of study-defined non-adherence (aOR: 1.85, 95% CI: 1.05, 3.28; aOR: 2.13, 95% CI: 1.11, 4.05), while availability of ER/PR status was associated with lower odds of non-adherence (aOR: 0.18, 95% CI: 0.09, 0.36). CONCLUSIONS: Radiotherapy is likely underutilized for women with breast cancer, even in a setting with public sector availability. Exploring patient-level factors that influence adherence to care may provide clinicians with better tools to support adherence and improve survival. Greater investment is needed in multidisciplinary, multimodality care for breast cancer in SSA.
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Neoplasias da Mama/radioterapia , Cooperação do Paciente/estatística & dados numéricos , Adulto , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Institutos de Câncer , Feminino , Acessibilidade aos Serviços de Saúde , Mau Uso de Serviços de Saúde/estatística & dados numéricos , Humanos , Mastectomia/estatística & dados numéricos , Pessoa de Meia-Idade , Terapia Neoadjuvante/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , ZimbábueRESUMO
PURPOSE: In sub-Saharan Africa, radiotherapy (RT) utilization and delivery patterns have not been extensively studied in patients with metastatic breast cancer. METHODS: A retrospective cohort study of female patients with metastatic breast cancer seen at Parirenyatwa Radiotherapy Centre in Zimbabwe from 2014 to 2018 was conducted. Demographics, pathology, staging, and treatment data were abstracted through chart review. Fisher's exact test and chi-squared test of independence were used to compare proportions, and independent two-sample t-tests were used to compare means. RESULTS: Of 351 patients with breast cancer, 152 (43%) had metastatic disease, median age 51 years (interquartile range: 43-61 years). Of those with metastatic disease, 30 patients (20%) received radiation to various metastatic sites: 16 spine; three nonspine bone metastases; six whole brain; and five chest wall or supraclavicular. Patients who received radiation were younger (46 v 52 years; P = .019), but did not differ significantly by performance status than those who did not. The most common dose prescription was 30 Gy in 10 fractions (33%). Five (17%) patients had treatment interruption and two (7%) had treatment noncompletion. Province of origin and clinical tumor stage were significant predictors of RT receipt (P = .002; and P = .018, respectively). CONCLUSION: A minority of patients with metastatic breast cancer received RT (20%), and these were likely to be younger, with advanced tumor stage, and resided in provinces where RT is available. Conventional courses were generally prescribed. There is a need to strongly consider palliative RT as an option for patients with metastatic breast cancer and use of hypofractionated courses (e.g. 8 Gy in one fraction) may support this goal.
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Neoplasias da Mama , Radioterapia (Especialidade) , Neoplasias da Mama/radioterapia , Feminino , Humanos , Pessoa de Meia-Idade , Cuidados Paliativos , Estudos Retrospectivos , ZimbábueRESUMO
Radiotherapy is an essential component of cancer therapy. Lack of access to radiotherapy in less-developed countries prevents its use for both cure and symptom relief, resulting in a significant disparity in patient suffering. Several recent initiatives have highlighted the need for expanded access to both palliative medicine and radiotherapy globally. Yet, these efforts have remained largely independent, without attention to overlap and integration. This review provides an update on the progress toward global palliative radiotherapy access and proposes a strategic framework to address further scale-up. Synergies between radiotherapy, palliative medicine, and other global health initiatives will be essential in bringing palliative radiotherapy to patients around the globe.
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Países em Desenvolvimento , Acessibilidade aos Serviços de Saúde/economia , Agências Internacionais/organização & administração , Cuidados Paliativos/métodos , Radioterapia (Especialidade)/organização & administração , Equipamentos e Provisões , Saúde Global , Alocação de Recursos para a Atenção à Saúde/economia , Mão de Obra em Saúde/organização & administração , Humanos , Agências Internacionais/economia , Cuidados Paliativos/economia , Radioterapia (Especialidade)/economia , Integração de SistemasRESUMO
The burden of cancer in low- to middle-income countries is growing and is expected to rise dramatically while resources to manage this disease remain inadequate. All authorities for the management of cancer recommend multidisciplinary care. Educational efforts by international organizations to assist local professionals in caring for their patients tend to have a lasting impact because they empower local professionals and enhance their skills. A multidisciplinary cancer management course was designed by American Society of Clinical Oncology staff and local experts to provide a roadmap for cross-specialty interaction and coordination of care in Zimbabwe. The outcome of the course was measured through feedback obtained from participants and impact on local workforce. The cancer management course was relevant to daily practice and fostered long-lasting partnerships and collaborations. Furthermore, it resulted in a more motivated local workforce and strengthened existing multidisciplinary practices. Cancer care is in a critical state in low- to middle-income countries. Educational efforts and collaborative partnerships may provide a cost-effective strategy with sustainable benefits. A multidisciplinary approach to optimize therapy is desirable. Evaluation of the course impact after a period of 6 months to 1 year is needed to determine the sustainability and impact of such efforts.