G Wessels

Stellenbosch University, Stellenbosch, Province of the Western Cape, South Africa

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Publications (35)46.54 Total impact

  • Article: Tuberculosis in oncology patients.
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    ABSTRACT: There is a dearth of studies addressing the incidence and clinical presentation of tuberculosis (TB) in children with cancer. To evaluate the incidence of TB in paediatric oncology patients at Tygerberg Hospital, located in a Cape Town area of high TB prevalence, and to describe the clinical characteristics of the disease in this particular group of patients whose treatment typically suppresses their immune response. We reviewed the records of 625 paediatric oncology patients admitted from 1 January 1991 to 31 December 2005. Of these, 87 received treatment for TB; however, only 57 cases had sufficient data to support a diagnosis of TB and only these were used for further analysis. In the children with TB, acute lymphoblastic leukaemia (ALL) was the most common malignancy (13/57, 22.8%). The incidence of TB in the study group was 9117/100,000/year, which is 22 times higher than the overall TB incidence reported in children from a similar background. Importantly, 47% of the active infections appeared in the 1st 5 months of chemotherapy, suggesting reactivation of latent TB. Identifying latent TB in our patients and providing prophylactic treatment during the initial months of chemotherapy might have prevented disease progression in these cases. Routine screening of paediatric oncology patients for latent TB infection and exclusion of active disease prior to initiation of cancer therapy might be indicated in TB-endemic areas.
    Annals of Tropical Paediatrics International Child Health 07/2008; 28(2):111-6. · 0.90 Impact Factor
  • Article: The effect of vitamin A status in children treated for cancer.
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    ABSTRACT: Chemotherapy for cancer can cause immunocompromise. The authors speculated that children with cancer and low vitamin A plasma levels were more susceptible to cancer treatment-related complications than children who are not vitamin A deficient. A cohort of 49 children with cancer were followed from diagnosis until death or for at least 5 years. Plasma retinol levels were determined at diagnosis. Complications of treatment were recorded. Children with low retinol levels at diagnosis tended to have more chance to develop febrile neutropenia (p = .052). Children with fever had lower mean vitamin A levels at diagnosis than those who did not suffer febrile episodes. In a childhood population with a high prevalence of vitamin A deficiency, routine vitamin A assessment and supplementation in children with cancer appears indicated.
    Pediatric Hematology and Oncology 07/2008; 25(4):283-90. · 0.89 Impact Factor
  • Article: Malignant liver tumors in South African children: a national audit.
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    ABSTRACT: Malignant liver tumors (mostly hepatoblastoma [HB] and hepatocellular carcinoma [HCC]) are uncommon, representing 0.5%-2% of childhood malignancies worldwide. The pattern of liver tumors appears to differ in Southern Africa as a result of infectious factors (e.g., hepatitis B/retroviral disease (HIV). This study aimed to assess recent changes in the prevalence and surgical management of liver tumors in South African children. Data were obtained from the tumor registry and pediatric oncology units in South African hospitals to audit and review the epidemiology, treatment, and outcome of malignant hepatic tumors in South African children. Malignant primary hepatic tumors were reported in 274 children (ages 0-14 years) from 1988 through June 2006. Of these 134 (48%) had HB; 77 (27%) had HCC (9 [3%] fibrolamellar subtype); 38 (13%), vascular tumors; and 17 (6%), liver sarcomas. In a further 8 patients (3%) other tumors included lymphoma and endodermal sinus tumor. Vascular tumors included hemangioendotheliomas (12), and there were 5 malignant tumors in children with HIV, including 1 angiosarcoma and 13 Kaposi sarcoma-like tumors. Hepatoblastoma occurred at a mean age of 1.47 years, and none were encountered in patients > 4 years of age. Hepatocellular carcinoma mostly occurred in the older patients (mean age: 10.48 years), but 6% presented in patients < 8 years of age (10 months, 2, 2.6, 5, 5, and 6 years). Hepatic sarcoma occurred at a mean age of 7.66 years and had a female predominance (M:F ratio: 0.4). The relative HCC prevalence (male predominant: hepatitis B related) was reflected in the low HB:HCC (1.67) ratio. However, a significant decrease in HCC was attributed to the effect of hepatitis B inoculation. There appeared to be an increase in the incidence of vascular tumors, presumably the result of an increase in Kaposi-like sarcoma in retrovirus-positive patients. The surgical resection rate was low because most patients presented late, with advanced disease. Survival was 11% and 52% for HB and HCC, respectively, and was related to chemotherapeutic response and complete surgical resection. Liver tumors appear to have a different epidemiological pattern in South Africa. The observed increased HCC prevalence appears to be decreasing with hepatitis B vaccination. Retroviral disease does not yet appear to have a major influence on the distribution of liver tumors in South Africa, although it possibly affects the vascular tumor prevalence.
    World Journal of Surgery 07/2008; 32(7):1389-95. · 2.36 Impact Factor
  • Article: Hemopure transfusion in a child with severe anemia.
    D C Stefan, R Uys, G Wessels
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    ABSTRACT: A 23-month-old girl presented with heart failure from extremely severe sickle cell anemia. The family refused blood transfusion on religious grounds (Jehovah's Witness). Alternative options acceptable to this religion, such as iron, erythropoietin, or folic acid were rejected as useless in the particular situation of the child. The patient was transfused with Hemopure, a product that consists of polymerized bovine hemoglobin. This is the first case reported in the literature of a child transfused, in an emergency situation, with this product.
    Pediatric Hematology and Oncology 07/2007; 24(4):269-73. · 0.89 Impact Factor
  • Article: Improved outcome in South African children of mixed ethnicity treated for all.
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    ABSTRACT: A historical cohort study with an analytical component was conducted to determine whether risk-appropriate chemotherapy can improve survival in children of mixed ethnicity with ALL. Eighty-one coloured children treated for ALL in South Africa were divided into 2 groups: group A (n = 39), treated prior to 1992, and group B (n = 42), treated after 1992. A comparison was made of survival, treatment complications, and supportive measures. The two groups were comparable. The mean nadirs of the white cell count (p < .01), platelet count (p = .01), and hemoglobin value (p < .01) were significantly lower in group B. The survival rate of 37% in group A improved to 66% in group B (p = .025). The results show that a risk-adapted regimen increased survival in children of mixed ethnicity in the Western Cape, despite increased hematological toxicity and episodes of febrile neutropenia.
    Pediatric Hematology and Oncology 07/2006; 23(4):329-38. · 0.89 Impact Factor
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    Article: Follow-up of a suspected excess of brain tumours among Namibian children.
    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde 11/2005; 95(10):776, 778, 780. · 2.04 Impact Factor
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    Article: Incidence of acute lymphoblastic leukaemia in white and coloured children in the Western Cape.
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    ABSTRACT: Objectives. To record the age-specific incidence rate (ASIR) for diagnosed acute lymphoblastic leukaemia (ALL) in coloured and white children aged 0 - 12 years in the Western Cape (WC). A retrospective population-based study using the 1991 population census to calculate the mean annual childhood population and the ASIR for ALL in the 0 - 4, 5 - 9 and 10 - 12-year age groups in rural and Cape Town metropolitan areas for the period 1983 - 1999. Odds ratios were calculated using EpiInfo 2000. Registry records of the paediatric cancer units at Tygerberg and Red Cross War Memorial Children's hospitals where all children with ALL in the WC were initially treated. All white and coloured children aged 0 - 12 years diagnosed as having ALL from 1983 - 1999. The ASIR by age and ethnic group in rural and metropolitan patients in the WC. The estimated annual childhood population in 1991 was 709 151 with 80.4% coloured and 19.6% white children, of whom 60% were resident in the Cape Town metropolitan area and 40% in the rural area of the WC. Of 246 children with ALL diagnosed in the period 1983 - 1999, 144 were male and 102 female. The ASIR in coloured children aged 0 - 4 years was 17.1/10(6) in the rural and 30.5/10(6) in the metropolitan area, compared with 55.7/10(6) and 56.2/10(6) respectively in white children. In the 5 - 9-year age group the ASIR in coloured children was 10.0/10(6) in the rural and 16.6/10(6) in the metropolitan area compared with 27.6/10(6) and 26.7/10(6) respectively in white children. The 10 - 12-year age group had comparable incidence rates in both populations and geographical areas. Only one case occurred within a 20 km radius of the Koeberg nuclear reactor. White children have an ASIR for ALL comparable to rates of diagnosis in the USA, while only half as many coloured children aged 0 - 9 years were diagnosed in both the rural and metropolitan areas. This contrast may indicate significant underdiagnosis of ALL in coloured children over the period in question. The change in health policy since 1994, which has improved access to primary health care, may improve the rate of diagnosis among coloured and black children.
    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde 08/2004; 94(7):533-6. · 2.04 Impact Factor
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    Article: Haemophilia patients aged 0-18 years in the Western Cape.
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    ABSTRACT: To record the number of haemophilicas aged 0-18 years in the Western Cape (WC), what event led to the diagnosis, the level of clotting factor, treatment, functional status of their joints and impact of the disease on the family. A prospective study of patients registered with the South African National Haemophilia Registry and new patients, utilising the patients' paediatricians, hospital records, patient and guardian interviews, physical examination and provincial nurse haemophilia co-ordinators. Haemophilia care centres at the three WC academic hospitals, regional hospitals and homes of patients. Two elective medical students, MHH and JJH, collected the information. All boys with confirmed haemophilia A or B in the WC. Events that led to diagnosis, degree of haemophilia, use of clotting factor, functional status, and effect on family. Of 78 patients (59 haemophilia A, 19 haemophilia B) identified, 49 could be studied. Forty-three per cent had severe, 29% moderate and 22% mild disease (6% unknown). Family history was present in 49%, but led to diagnosis in only 12%. The most common first symptoms were subcutaneous and mucosal bleeding. Delay in diagnosis varied from 0 to 9 months. Twenty-nine per cent of guardians were suspected of child abuse. RSA produced clotting factor was used 'on demand' in 73% of patients, for periodic prophylaxis in 20% and as continuous prophylaxis in 7%. Joints were functionally restricted in 43% of patients. The majority of guardians (59%) said the disease had a major impact on the family. The diagnosis of haemophilia in children with a positive family history was often delayed. Haemophilia causes significant morbidity in our patients and their families.
    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde 11/2003; 93(10):793-6. · 2.04 Impact Factor
  • Article: Long term survival of children with Burkitt lymphoma in Malawi after cyclophosphamide monotherapy.
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    ABSTRACT: Between 1991 and 1997, limited funding at times restricted available treatment for children with Burkitt lymphoma (BL) to cyclophosphamide (CPM) monotherapy at Lilongwe Central Hospital, Malawi. Our objective was to assess long-term survival in Malawian children with Burkitt lymphoma (BL) who had received one or more treatments with intravenous CPM at 40 mg/kg/dose at 14-day intervals. The study population consisted of 92 children in whom BL had been confirmed on fine needle aspirates (FNA), a home address had been documented on discharge from hospital, and the treatment records could be verified. Only the clinical site(s) of disease had been recorded. The M:F ratio was 1.4 and median age 8 years. A clinical officer on motorcycle attempted to locate the given addresses and interview parents or other sources. In 19 patients, the address was incorrect. Of 73 evaluable patients, 40 children are alive at a mean follow-up time of 59 (range: 29-104) months. The survival rate was 63.5% in 52 children with BL of the head only, and 33.3% in 21 children with primary disease involving the abdomen or other sites. Survivors had received a median number of 6 (range: 1-12), non-survivors 4 (range: 1-12), and untracable children 3 (range: 1-11) courses of CPM. We confirmed that CPM could cure children with facial and abdominal BL. The unavoidable bias in the selection of patients and the variable amount of CPM given, precludes accurate survival estimates. A prospective study with proper staging, assessment of FNA, marrow and cerebrospinal fluid with modern techniques, a standard treatment protocol, and adequate follow-up will better define the current therapeutic value of CPM monotherapy. CPM can be purchased at about 3 US dollars per 500 mg.
    Medical and Pediatric Oncology 02/2003; 40(1):23-5.
  • Article: Viral isolates during febrile neutropaenia in children with cancer.
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    ABSTRACT: We prospectively studied South African children with cancer for viral isolates during episodes of febrile neutropaenia. Viruses were found in seven (31.8 per cent) and bacteria in five (22.7 per cent) of 22 episodes. The most common isolate was the herpes simplex virus and the most common source was from nasopharyngeal aspirates. There was no dual detection of viral and bacterial isolates. This study emphasizes the important contribution of viruses to febrile neutropaenia.
    Journal of Tropical Pediatrics 03/2000; 46(1):21-4. · 1.39 Impact Factor
  • Article: Neuroblastoma in southern Africa: epidemiological features, prognostic factors and outcome.
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    ABSTRACT: We retrospectively analysed the epidemiological features and the importance of biochemical, histological and genetic parameters in predicting survival in 14 Namibian and 34 South African children treated for neuroblastoma (NB) from 1983 to 1997. Curative treatment consisted mainly of total (13%) or partial (44%) resection after chemotherapy (cyclophosphamide and doxorubicin x6 courses or carboplatin, etoposide, epirubicin and cyclophosphamide x6 courses). Localized radiotherapy with curative intent was given to 33% of patients. The male:female ratio was 0.9. The median age was 18 months (range 1-116) and was comparable in white, black and mixed ethnic patients. Primary disease was located in the abdomen (75%), thorax (15%), pelvis (5%) or elsewhere (5%). Evans stage distribution was: stage I, 2%; stage II, 19%; stage III, 21%; stage IV, 50%; and stage IVS, 8%. Stage III/IV disease was more common in black than in white children (p = 0.0001). Urinary vanillyl mandelic acid was elevated in 63% of those tested. Survival after 5-163 months' follow-up was 90% for stages I and II combined (median 2983, range 798-4661 days), 51% for stage III (median 367, range 61-5001 days), 6% for stage IV (median 227, range 20-4379 days) and 50% for stage IVS (median 532, range 54-1543 days). All seven children with para-spinal tumours survived. Individual factors associated with significantly poorer survival were elevated serum lactate dehydrogenase (p < 0.001), Joshi histological risk categorization adapted for age (p = 0.039), n-myc amplification (p = 0.006) and diploidy or tetraploidy (p = 0.006). All seven children with serum ferritin exceeding 149 ng/ml at the time of diagnosis died and survival was 33% in children with 1p deletion and 67% in those without, but the numbers were too small to achieve significance. These findings confirm the benefit of simple biochemical tests and histology in identifying those who are likely to respond favourably to conventional chemotherapy and surgery. Supportive genetic tests on formalin-fixed paraffin-embedded tumour tissue contributed to predicting outcome in 21 patients.
    Annals of Tropical Paediatrics International Child Health 12/1999; 19(4):357-63. · 0.90 Impact Factor
  • Article: Haematological abnormalities in children with tuberculosis.
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    ABSTRACT: Over a 16 month period 307 children with suspected tuberculosis (TB) and an available full blood count (FBC) seen at Tygerberg Hospital in South Africa were evaluated and categorized as confirmed (A), probable (B), and no TB (C) according to WHO criteria. There was no difference in the mean age of the 168 group A (33.6 months), 83 group B (34.4 months), and the 56 group C (31.6 months) children. A lower mean haemoglobin (Hb 10.2 vs. 10.8 g/dl) was the only significantly different haematological parameter in children with TB compared with the comparison group (Group C). There were no differences in median total white cell count, neutrophils, lymphocytes, monocytes, platelets, or the proportion of children in each group with anaemia, microcytosis, neutrophilia, neutropenia, lymphocytosis, lymphopenia, monocytosis, thrombocytosis or thrombocytopenia. The most common haematological abnormalities in children with TB were the presence of anaemia, neutrophilia, and monocytosis but these changes were found with equal frequency in control patients. Although haematological abnormalities are fairly common in children with TB, in a developing country these abnormalities also occur frequently in children with other non-tuberculosis respiratory infections. An FBC has no diagnostic predictive value when investigating a child for TB.
    Journal of Tropical Pediatrics 11/1999; 45(5):307-10. · 1.39 Impact Factor
  • Article: Experience with high dose dexamethasone in the treatment of chronic symptomatic immune thrombocytopaenia.
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    ABSTRACT: To evaluate the efficacy of high dose dexamethasone (HDD) as treatment for symptomatic chronic immune thrombocytopaenia (ITP). A non-randomised intervention study with final evaluation one year after treatment, comparing findings before and after intervention. Tygerberg University Hospital, South Africa. A consecutive sample of six children with chronic (duration more than six months) ITP. The diagnosis of ITP was based on a platelet count of < 100 x 10(9)/1 together with appropriate clinical, laboratory and bone marrow findings. All children treated with dexamethasone 0.5 mg/kg/day intravenously for four days every 28 days for a total of six cycles. A rise in platelet count maintained for a least one year associated with the disappearance of symptoms due to thrombocytopaenia. Treatment was easy to administer and well tolerated with transient side effects in only two children. Three patients had a rise in platelet count of > 50 x 10(9)/1 during treatment and three had platelet counts of > 30 x 10(9)/1 after completion of therapy but only one at one month and one at six months after completion of the six courses respectively. None of the patients showed a sustained rise in platelet count during and after HDD treatment. HDD did not cause a significant sustained rise in the platelet count in children with chronic symptomatic ITP. If high dose prednisone and IVIG fail, a splenectomy should be considered in children over five years of age.
    East African medical journal 10/1999; 76(10):571-4.
  • Article: The mother-to-child HIV transmission debate.
    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde 03/1999; 89(2):104, 106. · 2.04 Impact Factor
  • Article: Bone mineral density in long-term survivors of childhood cancer.
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    ABSTRACT: Bone mineral density (BMD) of the lumbar spine was measured in 97 long-term survivors of childhood cancer 5-23 years after diagnosis using dual-energy X-ray absorptiometry (DXA). They had been treated for acute leukemia (n = 22), brain tumors (n = 16), lymphomas (n = 16), Wilms' tumor (n = 10), neuroblastoma (n = 7) and other cancers (n = 26). The correlations between BMD and the Z-scores for weight for height, height for age and weight for age at diagnosis and follow-up were evaluated with stepwise multiple regression. Correlations with cumulative corticosteroid and radiation dose were examined with Spearman's correlation coefficient. The number of nature of fractures were noted. A BMD Z-score of below -2 was present in 13 and a BMD Z-score of -1 to -2 in 31 children. In total, a low BMD was observed in 45% of children. Height for age at follow-up correlated significantly with BMD Z-score. Increasing doses of cranial irradiation (18-54 Gy) were associated with lower BMD (p = 0.001, Spearman). This was true also for 22 children with acute lymphoblastic leukemia (ALL) who had received 18-24 Gy cranial irradiation (p = 0.04, Spearman). Fractures occurred in 14 children following trauma. The difference in BMD Z-scores of children with and without fractures did not achieve statistical significance although the majority of the children with fractures had low BMD Z-scores. The significant inverse correlation between height for age at follow-up and BMD must be interpreted with the realization that DXA is not a volumetric measurement of BMD and that short stature is associated with a smaller skeletal mass.
    International journal of cancer. Supplement = Journal international du cancer. Supplement 02/1998; 11:44-7.
  • Article: Hodgkin's disease in children in southern Africa: epidemiological characteristics, morbidity and long-term outcome.
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    ABSTRACT: We reviewed 39 children < 15 years of age treated for Hodgkin's disease (HD) from 1973 to 1996. There were seven black, 12 white and 20 coloured children (of mixed ethnic origin). The M:F ratio was 2.9:1 and the median ages 147, 124 and 119 months in white, coloured and black children, respectively. Coloured and black children came mainly from a poor socio-economic background. Cervical lymphadenopathy was present in 74% and systemic symptoms in 51% of cases. Five per cent had clinical stage I, 41% stage II, 28% stage III and 26% stage IV disease. Two children underwent a staging splenectomy. The majority of white children presented with stages I and II and the majority of black and coloured children with stages III and IV HD. Nodular sclerosing (59%), mixed cellularity (40%) and lymphocyte-depleted (43%) were the most common histological subtypes in white, coloured and black children, respectively. Epidemiologically, white children fitted the criteria for HD type I and coloured and black children the criteria for HD type III. Nineteen children were treated with ChlVPP (chlorambucil, vinblastine, prednisone, procarbazine) and 20 with MOPP (mustine, Oncovin, procarbazine, prednisone) and/or ABVD (Adriamycin, bleomycin, vinblastine, DTIC) with involved field radiotherapy to bulky mediastinal disease. The projected 10-year survival after ChlVPP or MOPP/ABVD therapy was similar at 52%. In stages I and II, HD projected survival at 5 and 10 years was 85%, and in stages III and IV it was 82% at 5 and 48% at 10 years. The relapse rate was 47% in stage II, 45% in stage III and 44% in stage IV. Tuberculosis was suspected and treated in five children at the time of, and in seven children (three confirmed) subsequent to, the diagnosis of HD. Varicella developed in six and herpes zoster in five children. Five treatment-related deaths were due to septicaemia following splenectomy (two), marrow failure, corpulmonale and secondary leukaemia.
    Annals of Tropical Paediatrics International Child Health 12/1997; 17(4):367-73. · 0.90 Impact Factor
  • Article: Incidence and frequency rates of childhood cancer in Namibia.
    G Wessels, P B Hesseling
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    ABSTRACT: To estimate the extent of paediatric malignancy in an African country and to compare these findings with paediatric cancer rates in other countries. A retrospective descriptive study which calculated incidence and frequency rates from the data obtained from a 6-year survey of childhood cancer in Namibia. Children from the general community who were referred by primary care physicians or clinics and diagnosed in peripheral district hospitals or a tertiary care institution. A total of 163 children less than 15 years of age diagnosed with any malignant neoplasm, intracranial tumour or histiocytosis between 1983 and 1988. None. The minimum overall incidence of childhood cancer recorded in Namibia was lower than the rates usually reported by economically privileged countries. The rates of certain malignancies corresponded to the rates recorded in other African countries. The overall incidence of childhood cancer was 55.5 per million. Tumours of the central nervous system occurred most commonly (18%), followed by renal tumours (14%), leukaemia (12%) and lymphoma (11.5%). The 5.8 per million incidence rate of retinoblastoma was similar to the rates recorded in other African countries but higher than in the UK or the USA. The incidence rates per million children for renal tumours, malignant bone tumours and soft-tissue sarcomas were 7.4, 4.8 and 5.2, respectively, which correspond with the rates in Western Europe and the USA. The incidence rate of CNS tumours was only 9.3 per million. Both leukaemia (6.5 per million) and lymphoma (6.3 per million) had rates far lower than those recorded in central Africa or developed Western countries. The incidence pattern of childhood cancer in Namibia demonstrates features of both the patterns described as typical for Africa and those described for industrialised countries.
    South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde 08/1997; 87(7):885-9. · 2.04 Impact Factor
  • Article: Teratomas in infancy and childhood at Tygerberg Hospital, South Africa, 1973 to 1992.
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    ABSTRACT: To document the childhood teratomas at Tygerberg Hospital and compare the profile with other African series. Retrospective review of the clinicopathologic features of 43 cases of childhood teratomas. Tumors were classified according to the World Health Organization criteria for germ cell tumors. Tygerberg Hospital, University of Stellenbosch, Cape Town, South Africa. There were 26 mature, 15 immature, and 2 malignant teratomas. The most common sites were the ovaries and the sacrococcygeal region. Testicular teratomas were absent. The female-to-male ratio for black patients was 5.5:1. There was a peak age incidence in the first 4 years of life, with sacrococcygeal teratomas predominating. A second, smaller peak between 12 and 15 years was seen owing to ovarian teratomas. Immature teratomas presented at an earlier age than mature teratomas. The majority of ovarian teratomas occurred in patients of mixed race, whereas the extragonadal teratomas were distributed more evenly among the race groups. In black patients and patients of mixed race mature teratomas predominated, whereas in white patients immature teratomas were most common. The increased occurrence of teratomas among female patients, the large number of ovarian teratomas, the absence of testicular teratomas, and the low incidence of malignant teratomas correspond to the observations of other African series. Certain differences are apparent among the three race groups, namely, a high ratio of female-to-male patients in the black group, a predominance of ovarian teratomas in the mixed-race and black groups, and a predominance of extragonadal and immature teratomas in the white group.
    Archives of pathology & laboratory medicine 06/1997; 121(5):499-502. · 2.58 Impact Factor
  • Article: An analysis of prognostic variables in acute lymphocytic leukaemia in a heterogenous South African population.
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    ABSTRACT: The records of all 96 children below the age of 15 years diagnosed with acute lymphoblastic leukaemia at Tygerberg Hospital in the Republic of South Africa between 1983 and 1995 were reviewed to determine risk factors which may predict poor outcome. Age < 2 and > 8 years, and white cell count > 20 x 10(9)/l at diagnosis were significant predictors of poor outcome. Sex, FAB classification, immunophenotype, hepatomegaly, splenomegaly, BFM risk score, and the presence of mediastinal glands did not predict outcome. The presence of the established risk factors could not adequately explain the difference in 5-year event-free survival in the three ethnic groups which was 67 per cent in white, 17 per cent in black, and 38 per cent in children of mixed ethnic origin. In an attempt to improve survival in black children, our stratification of risk groups will in future be based on factors that include ethnicity, age and WCC > or = 20 x 10(9)/l at diagnosis. Pediatric oncology services in developing countries should adapt therapy to the risk factors of their local populations.
    Journal of Tropical Pediatrics 06/1997; 43(3):156-61. · 1.39 Impact Factor
  • Article: Hepatocellular carcinoma in children.
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    ABSTRACT: Hepatocellular carcinoma (HCC) occurs more frequently in subsaharan Africa and the Orient than in other geographical regions, but remains an uncommon tumour of childhood. We review six children with HCC (mean age 13 years) treated by the paediatric oncology unit at Tygerberg Hospital in Cape Town over an 8-year period (1983 - 1990). Patients presented with epigastric and right upper quadrant discomfort and hepatomegaly. The hepatitis B serum antigen (HbsAg) was positive in three patients; serum alpha-fetoprotein (AFP) levels were markedly elevated in three (range 100 - 453,000 microg/l). Age and sex did not differ significantly and all patients initially had irresectable advanced-stage tumours. Morphologically, three were highly malignant adult-type pleomorphic HCCs, two were differentiated tumours, and one a fibrolamellar subtype. The mean 2-year survival was 33% and the 5-year survival 16.6%. The biological behaviour and response to treatment of the tumours varied. Whereas three patients had a poor response to therapy, two with poorly-differentiated tumours, negative HbsAg, and normal serum AFP levels responded to doxorubicin/cisplatinum chemotherapy. This facilitated radical surgical excision. One patient of this group has survived for more than 75 months following surgical resection and remains well. HCC remains an uncommon tumour of childhood with a high mortality. Aggressive chemotherapeutic regimes in combination with surgical resection may lead to improved survival in some cases. Prevention of hepatitis B remains a priority.
    Pediatric Surgery International 05/1997; 12(4):266-70. · 1.25 Impact Factor

Institutions

  • 1995–2008
    • Stellenbosch University
      • • Division of Paediatric Surgery
      • • Department of Paediatrics and Child Health
      • • Division of Anatomical Pathology
      Stellenbosch, Province of the Western Cape, South Africa
  • 1992–2008
    • tygerberg hospital
      Cape Town, Province of the Western Cape, South Africa
  • 2003
    • Academisch Medisch Centrum Universiteit van Amsterdam
      • Academic Medical Center
      Amsterdam, North Holland, Netherlands