Acute lymphoblastic leukaemia (ALL) is associated with a compromised myeloid system. Understanding the state of granulopoiesis in a patient during treatment, places the clinician in an advantageous ...position. Mathematical models are aids able to present the clinician with insight into the behaviour of myeloid-derived leucocytes. The main objective of this investigation was to determine whether a proposed model of ALL during induction therapy would be a usable descriptor of the system. The model assumes the co-occurrence of the independent leukaemic and normal marrow populations. It is comprised of four delay-differential equations, capturing the fundamental characteristics of the blood and bone marrow myeloid leucocytes and B-lineage lymphoblasts. The effect of treatment was presumed to amplify cell loss within both populations. Clinical data was used to inform the construction, calibration and examination of the model. The model is promising-presenting a good foundation for the development of a clinical supportive tool. The predicted parameters and forecasts aligned with clinical expectations. The starting assumptions were also found to be sound. A comparative investigation highlighted the differing responses of similarly diagnosed patients during treatment and further testing on patient data emphasized patient specificity. Model examination recommended the explicit consideration of the suppressive effects of treatment on the normal population production. Additionally, patient-related factors that could have resulted in such different responses between patients need to be considered. The parameter estimates require refinement to incorporate the action of treatment. Furthermore, the myeloid populations require separate consideration. Despite the model providing explanation, incorporating these recommendations would enhance both model usability and predictive capacity.
In 2008 the South African Children's Cancer Study Group decided to review the epidemiology, management, and chemotherapy response of HIV-positive children with malignancy.
This is a retrospective ...analysis of data collected from the records of HIV-positive children diagnosed with malignancy at 7 university-based pediatric oncology units serving 8 of the 9 provinces in South Africa.
Two hundred eighty-eight HIV-positive children were diagnosed with 289 malignancies between 1995 and 2009. Age at diagnosis ranged from 17 days to 18.64 years; median 5.79 years. Of the 220 HIV-associated malignancies, there were 97 Kaposi sarcomas, 61 Burkitt lymphomas, 47 other B-cell lymphomas including 2 primary central nervous system lymphomas, 12 Hodgkin lymphomas, and 3 leiomyosarcomas. Sixty-nine patients presented with non-AIDS-defining malignancies. More than 80% presented with advanced disease. Most patients (76.7%) were naive to antiretroviral therapy; 22.2% did not have access because it only became available in public hospitals in 2004. One hundred ninety-seven children were treated with curative intent; 91 received palliative care due to advanced malignancy and/or advanced HIV disease. Nearly one third had coexisting pathology, mostly tuberculosis. Overall survival for the whole group was 33.7%, but was 57.8% for those treated with antiretroviral therapy and chemotherapy.
The study shows more Kaposi sarcoma and fewer primary central nervous system lymphomas among HIV-positive children than that is reported in the developed world, but confirms a higher incidence of non-Burkitt B-cell lymphoma than in HIV-negative children. The high number of non-AIDS-defining malignancies underscores the prevalence of HIV-AIDS in South Africa. The overall survival should improve with universal access to antiretrovirals and earlier diagnosis.
Background
Children with Hodgkin lymphoma (HL) have excellent survival rates in high‐income countries, but there are minimal outcome data in South African patients. Differing approaches to treatment ...are used in centres across South Africa, and the South African Children's Cancer Study Group (SACCSG) embarked on a programme to audit outcomes to improve survival rates.
Patients and Methods
A multicentre study was conducted to analyse outcomes and prognostic factors of children with HL in South Africa. Ten dedicated South African paediatric oncology units participated in a retrospective data review. All patients with HL treated consecutively between January 2000 and December 2010 were included. Kaplan–Meier curves and Cox regression model were employed to determine survival rates and prognostic factors.
Results
Two hundred and ninety‐four patients were eligible for inclusion. The median age at presentation was 9.6 years (range 2.9–18.8); 55.4% of the patients presented with Stage III and IV disease and 9.9% were human immunodeficiency virus (HIV) positive. First‐line therapy consisted of adriamycin, bleomycin, vinblastine and dacarbazine (ABVD) in 158 patients, vincristine, procarbazine/etoposide, prednisone and doxorubicin in 97 and adriamycin, bleomycin, vincristine and dacarbazine–chlorambucil, vinblastine, prednisone and procarbazine in 23 patients. The 5‐year overall survival (OS) was 79% (95% confidence interval 73–84%). Multivariate analysis demonstrated that HIV infection (P = 0.018) and Ann Arbor Stage III and IV disease (P = 0.006) conferred a poor prognosis, while treatment with ABVD was associated with higher survival rates (P = 0.028).
Conclusion
OS rates are encouraging for a middle‐income country, although economic disparities continue to impact negatively on outcomes. Study results will form the basis for the development of national protocol and continued advocacy to rectify disparities.
Kaposi sarcoma in South African children Stefan, D. Cristina; Stones, David K.; Wainwright, Linda ...
Pediatric blood & cancer,
03/2011, Letnik:
56, Številka:
3
Journal Article
Children with HIV and cancer show an excess of non-Hodgkin lymphoma and leiomyosarcoma when compared with children with malignancy but without HIV. This study aimed at: (1) comparing the distribution ...of various cancers in South African children with malignancies and HIV versus children with malignancies but without HIV and (2) comparing the outcomes after therapy.
This is a retrospective comparative study of 84 black children with cancer and HIV, consecutively admitted at Tygerberg Children's Hospital, Cape Town and Universitas Hospital, Bloemfontein, between 1995 and 2010, compared with 570 HIV-negative black children with malignant diseases, consecutively admitted at the 2 hospitals, between 2002 and 2010. Variables studied included age, sex ratio, number of cases of each malignancy, length of follow-up, treatment abandonment, and mortality. The statistical significance was tested with the Student t test and χ test for P≤0.05. Kaplan-Meyer survival curves were constructed.
The most frequent cancer was Kaposi sarcoma (39.3%), seen exclusively in children with HIV. Burkitt lymphoma was found more often (20.2%) in the HIV-positive group than in the HIV-negative one (2.8%, P<0.0001). Leiomyosarcoma, described as the second most frequent neoplasm encountered in HIV-positive children, was found in this series only once. The survival figures are much worse in the HIV-positive group: 26.2% versus 47.7% (P<0.0001), mainly due to drug toxicity.
Kaposi sarcoma and Burkitt lymphoma occurred more often in children with HIV. These children have a lower tolerance of chemotherapy, even when combined with HAART.
Pulmonary lymphoepithelioma-like carcinoma is a rare malignant tumour predominantly occurring in Asian patients. It has identical histological features to nasopharyngeal carcinoma. To date, ...Epstein–Barr virus (EBV) in pulmonary lymphoepithelioma-like carcinoma has been limited to the Asian population. This manuscript presents an unusual case in a 12-year-old African boy in which the tumour tested positive for EBV.
The South African Children's Tumour Registry was established 25 years ago as it was essential to collect data on malignant disease in the paediatric population that can be used for statistical ...research in an efficient and sustainable way. The Registry is a useful and significant repository of specific paediatric data, along with the recently revitalised National Cancer Registry, to serve the needs of the cancer research community.
Background: Wilms tumour is a comparatively common paediatric malignancy with a relatively good prognosis. Routine post-treatment surveillance at our institution currently includes regular ...abdominopelvic computed tomography (CT) over a two-year period for the early detection of disease recurrence. The rationale is that early salvage therapy may improve overall patient survival, and thus justifies the exposure to potentially harmful ionising radiation. Objective: To critically evaluate the routine use of post-treatment abdominopelvic CT by determining the detection rate of disease recurrence and associated clinical outcomes. Methods: Sixty-four patients in remission following initial treatment for Wilms tumour were included in this retrospective study. Variables obtained from patient records included gender, age, histological grading and tumour stage at presentation, number of abdominopelvic CT scans, site(s) of relapse, method of recurrence detection and confirmation, time to recurrence and clinical outcome. Results: The patients received a total of 334 surveillance abdominopelvic CT scans. Nine (14%) patients developed disease recurrence during the follow-up period. In three cases, the initial detection method was abdominopelvic CT. All three of these patients subsequently died despite salvage therapy (22 months median survival). Five false-positive diagnoses of recurrence occurred, with two being made on abdominopelvic CT. Conclusion: Routine post-treatment abdominopelvic CT showed a low detection rate of disease recurrence in children treated for Wilms tumour, while subjecting patients to a large radiation burden. The recommendation is that current practice be changed in line with the ultrasound-based Societe Internationale d'Oncologie Pediatrique (SIOP) imaging guidelines.
Families were interviewed as a quality improvement assessment for palliative and supportive care services for children.
This exploratory qualitative study of family members of children with cancer ...was conducted at an academic hospital in central South Africa and a grounded theory approach was used. Face-to-face interviews using a semi-structured interview guide were conducted with 16 family members of 16 children.
Parents felt supported by the healthcare professionals who were caring for their child, but several shortcomings were identified. These included erratic psychosocial support, minimal financial support and poor parental access to basic needs and food provision, preventable errors in procedures and a lack of support available for siblings. It is also worth noting that healthcare professionals did not always seem sufficiently equipped to attend to palliative care patients.
Strategies to improve supportive and palliative care are needed for children with cancer and their families in a hospital setting. The interviews identified a number of themes and current shortcomings that should be considered to improve services.