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G P Hadley

Publications and source records attributed to G P Hadley.

At least 19 recordsLinked to original sources
PubMed2006

The morbidity and outcome of surgery in children with large pre-treated Wilms' tumour: size matters.

Sixty-seven patients with resected Wilms' tumour>1.0 kg are reported. Surgery in this group is difficult, may result in the sacrifice of adjacent structures, and frequently upstages the patient. Mortality is related to tumour burden. Whilst there is little agreement on the therapeutic implications of failure to respond to neoadjuvant therapy, these surgical and anaesthetic hazards must be recognized, and alternative stratagems considered, prior to attempting a surgical procedure.

Antibiotics, Antineoplastic↗
PubMed2006

Hypertension in a cohort of African children with renal tumours.

Hypertension is a frequent problem in children with renal tumour, yet there are few reports from centres in the third world. A retrospective study of blood pressure in a cohort of 46 patients with renal tumours seen over a 3-year period was carried out. Fifty percent of patients presenting with Wilms' tumour were hypertensive. Serum concentrations of active renin correlated poorly with blood pressure. There was no correlation between serum concentrations of active renin and tumour mass or histology. Specific antihypertensive therapy was offered to 11 patients who had either neurological or cardiac complications of hypertension. All other patients with Wilms' tumour had their blood pressure controlled by neoadjuvant chemotherapy. Patients with mesoblastic nephroma were managed by primary surgery. Patients with asymptomatic hypertension may be monitored as hypertension will resolve with neoadjuvant chemotherapy. Those with compelling symptomatology will require additional hypertensive medication.

Africa↗
PubMed2006

Expression of E-cadherin, cadherin-11, alpha-, beta- and gamma-catenins in nephroblastomas: relationship with clinicopathological parameters, prognostic factors and outcome.

AIM: This study was undertaken to determine the expression of cell adhesion molecules E-cadherin, cadherin-11, and alpha-, beta- and gamma-catenins in nephroblastomas and to correlate this expression with pathological features and known prognostic factors. METHODS: Immunohistochemistry was performed on 140 cases of nephroblastoma following heat-induced epitope retrieval and using the streptavidin-biotin technique. RESULTS: E-cadherin was expressed in 75 cases (54%), cadherin-11 in 128 cases (91%), alpha-catenin in 93 cases (66%), beta-catenin in 133 cases (95%) and gamma-catenin in 22 cases (16%). Nuclear localisation of beta-catenin was not demonstrated. There was a statistically significant relationship between the administration of preoperative chemotherapy and the expression of E-cadherin, alpha- and gamma-catenin, respectively. These proteins were more frequently expressed in tumours treated with preoperative chemotherapy. Those tumours that expressed all four proteins (E-cadherin, alpha-, beta- and gamma-catenin) showed a statistically significant association with the administration of preoperative chemotherapy, in contrast to tumours that did not express all four proteins. CONCLUSION: Nephroblastomas show a heterogeneous distribution of staining for E-cadherin, cadherin-11, alpha-, beta- and gamma-catenins. Tumours treated with preoperative chemotherapy are more likely to express these molecules. The expression status of E-cadherin, cadherin-11 and the catenins in this cohort does not appear to be of prognostic value.

Adolescent↗
PubMed2005

Microsatellite analysis of the adenomatous polyposis coli (APC) gene and immunoexpression of beta catenin in nephroblastoma: a study including 83 cases treated with preoperative chemotherapy.

AIMS: To determine whether microsatellite mutations of the adenomatous polyposis coli (APC) gene have pathological or prognostic significance in nephroblastomas and to correlate APC alterations with beta catenin immunoexpression. METHODS: One hundred nephroblastomas were analysed, 83 of which received preoperative chemotherapy. Normal and tumour DNA was isolated using standard proteinase K digestion and phenol/chloroform extraction from paraffin wax embedded tissue. Polymerase chain reaction using four APC microsatellite markers-D5S210, D5S299, D5S82, and D5S346-was performed and the products analysed. Immunohistochemistry was performed using the LSAB kit with diaminobenzidine as chromogen. Results were correlated with clinicopathological data using the chi(2) test. RESULTS: Allelic imbalance/loss of heterozygosity was more frequent than microsatellite instability, with 30% of cases showing allelic imbalance/ loss of heterozygosity and 16% showing microsatellite instability. Although there was a significant correlation between the results for individual markers and the clinicopathological data, the overall results do not support a prognostic role for APC in nephroblastoma. Expression of beta catenin was seen in 93% of cases. Staining was predominantly membranous, with epithelium, blastema, and stroma being immunoreactive. Cytoplasmic redistribution was seen in 58% of cases, but no nuclear staining was detected. No significant associations between beta catenin expression and the clinicopathological parameters were found. Kaplan-Meier survival plots showed that patients with loss of membranous staining and pronounced cytoplasmic staining (score, 3) had a significantly shorter survival (p = 0.04; median survival, 5.87 months). CONCLUSION: Microsatellite analysis of APC and immunoexpression of beta catenin did not provide significant pathological or prognostic information in this cohort of nephroblastomas.

Adolescent↗
PubMed2004

Hepatocellular carcinoma and liver tumors in South African children: a case for increased prevalence.

BACKGROUND: The high regional incidence of hepatocellular carcinoma (HCC) in South Africa also may be present in children of the region, although the link to hepatitis B (HBV) appears less clear. The objective of this study was to assess the incidence and probable causes of HCC in South African children. METHODS: Data were obtained from seven participating pediatric oncology units and from the tumor registry to review hepatic tumors in children in South Africa. RESULTS: One hundred ninety-four children (ages 0-14 years) presented with malignant primary hepatic tumors (1988-2003). One hundred twelve tumors (57%) were hepatoblastoma (HB), 68 tumors (35%) were hepatocellular carcinoma (HCC) (including 9 patients with the fibrolamellar variant, 6 of which occurred in black children), 10 tumors (5%) were sarcoma of the liver, and 4 tumors were lymphoma. The ratio of HB to HCC (1.67) was markedly lower compared with other reports, suggesting a greater prevalence of HCC. Correlation with population statistics indicated an incidence of 1.066 malignant liver tumors per year per 10(6) children age < 14 years (HB, 0.61 per 10(6) children; HCC, 0.39 per 10(6)). Two-thirds of patients with HCC were positive for HBV surface antigen (HBsAg), and HCC occurred mostly in black African patients (93%). The mean age of onset was 1.47 years for HB and 10.48 years for HCC. A preponderance of males (3.5:1.0) was noted in the HBsAg-positive group that was not reflected elsewhere. Serum alpha-fetoprotein (AFP) levels were raised both in patients with HB (100%; most AFP levels were very high) and in patients with HCC (69%), although 15% of patients with HCC had low or normal AFP levels. CONCLUSIONS: It appeared from the current results that HCC is more prevalent among children in South Africa compared with the children in more developed countries, although their rates were lower that the rates noted in adults. A collaborative approach will be required to improve their diagnosis and management.

Adolescent↗
PubMed2004

Primary tumours of the liver in children: an African perspective.

Primary tumours of the liver present diagnostic and management difficulties. In Africa, outcomes reflect limitations imposed by comorbidity and lack of resources, both human and material, for major liver resection. Whilst hepatoblastoma and hepatocellular carcinoma can be readily distinguished on clinical and biochemical grounds, there is a high incidence of sarcomatous tumours that mandate biopsy. In our experience, hepatocellular carcinoma in childhood is a lethal condition, usually bilateral and associated with hepatitis B infection. Sarcomatous tumours are often resectable but have a high rate of local recurrence. Hepatoblastoma is a surgically curable tumour in many patients. Resection for benign liver tumours can be safely accomplished and augments institutional experience with major liver surgery.

Carcinoma, Hepatocellular↗
PubMed2004

Minimizing surgery in complicated intussusceptions in the Third World.

When presentation is delayed, intussusceptions may be difficult to reduce using standard enema regimens. Our endeavour to minimize the need for surgery in an environment where failed reductions are common has led to the development of an aggressive, non-operative method of reducing intussusceptions. One hundred and six patients with intussusception were reviewed with the aim of evaluating a new method of reducing intussusceptions suited to our Third World environment. In our cohort, delayed presentation was common, with 32% of patients presenting more than 48 h after the onset of the intussusception. On clinical grounds alone, 41% of patients required a primary laparotomy. Standard barium and air reductions for intussusception were rarely successful under these conditions i.e. 13% and 22%, respectively. By using an air enema under general anaesthesia in the operating theatre, the reduction rate has improved to 53%. This approach is suggested as a last attempt at reducing an intussusception prior to laparotomy following failed standard enema reduction, and as the first line of management in the attempted reduction in the patient with delayed presentation without symptoms of peritonitis.

Air↗
PubMed2004

Microsatellite analysis of the DCC gene in nephroblastomas: pathologic correlations and prognostic implications.

Microsatellite instability has been reported in a wide variety of cancer types. Inactivation or loss of tumour suppressor genes has been shown to result in cell cycle deregulation and neoplastic growth. We conducted a microsatellite study using fluorescent-based DNA technology to determine whether mutations in the microsatellite sequences of the deleted in colorectal cancer (DCC) gene, a tumour suppressor at 18q21.1, have any pathologic correlation or prognostic significance in nephroblastomas. Normal and tumour DNA was isolated from 106 cases of nephroblastoma using the standard proteinase K digestion and phenol-chloroform extraction method from paraffin wax-embedded tissue. Polymerase chain reaction using three microsatellite markers; D18S21, D18S34 and D18S58, for the DCC gene were performed. The polymerase chain reaction products were analysed on the ALF Express Automated DNA sequencer. The results were correlated with age at diagnosis, preoperative chemotherapy, clinicopathological stage, histological classification and patient outcome using chi(2) test. Allelic imbalance/loss of heterozygosity appeared to be a more frequent genetic aberration than microsatellite instability with 20% of cases showing allelic imbalance/loss of heterozygosity and only 9% of cases showing microsatellite instability. Genetic aberrations were more frequent in unfavourable histology tumours compared to favourable histology tumours (P=0.012). All patients with genetic aberrations for more than one DCC marker died independent of histological classification and stage (P=0.016). There was no statistically significant difference when DCC aberrations were compared with age at diagnosis, preoperative chemotherapy and clinicopathological stage. In conclusion, this study has found that multiple aberrations involving the DCC locus may play a role in the progression of nephroblastomas, and hence confer a poorer prognosis.

Adolescent↗
PubMed2004

Neonatal gastric perforation.

BACKGROUND: Gastric perforation in neonates is a catastrophe associated with high morbidity. Most are due to underlying primary pathology. OBJECTIVES: To review the management of gastric perforation in neonates in Kwa Zulu-Natal, South Africa. DESIGN: Retrospective study of consecutive complete data sets of neonates presenting with gastric perforation. SETTING: Department of Paediatric Surgery, Nelson R. Mandela School of Medicine, University of Natal, Durban, South Africa. SUBJECTS: Eight neonates treated for gastric perforation between January 1998 and April 2003. MAIN OUTCOME MEASURES: Morbidity and mortality. RESULTS: There was an equal number of males and females. Median birth weight was 2.0 kg with a range of 1.4 to 3.2 kg. Five of the eight neonates were premature. Primary pathologies were associated with perforation in seven of the eight neonates. Prematurity, low birth weight and pneumonia were contributing factors to the poor outcome. Sepsis was a complication in seven of the eight neonates leading to their death (88% mortality). CONCLUSION: Active perinatal management, early treatment of primary pathologies, and protection of the stomach against distension in neonates at risk are essential in the management of neonatal gastric perforation.

Female↗
PubMed2003

Gastro-intestinal tract perforation in neonates.

BACKGROUND: Gastro-intestinal tract (GIT) perforation in neonates is a serious problem associated with high mortality due to resulting sepsis. Co-morbid factors, eg. prematurity, respiratory problems, low birth weight, and nutritional factors, negatively affect the outcome. OBJECTIVES: To review the management outcome of gastro-intestinal tract perforation in neonates in KwaZulu-Natal and identify factors that require attention for better survival of neonates with GIT perforation. DESIGN: Retrospective study of consecutive complete data sets of patients presenting with a diagnosis of GIT perforation. SETTING: Department of Paediatric Surgery, Nelson R. Mandela School of Medicine, University of Natal, Durban, South Africa. SUBJECTS: Fifty four neonates treated for gastro-intestinal tract perforation between January 1998 and January 2003. MAIN OUTCOME MEASURES: Morbidity as determined by complications and mortality. RESULTS: More males (69%) were affected than females (31%). The median birth weight was 2.3 kg and median age at presentation was four days. Eighty nine percent were referred from peripheral hospitals. Abdominal distension was the leading symptom and sign (74%). Co-morbid factors were present in 89%, with prematurity as the leading factor (52%). Necrotising enterocolitis (NEC) was the main cause of perforation (33%) and the terminal ileum was the most common site. Most (56%) were treated by excision and primary repair of perforations. Sepsis was the leading complication (44%) and major cause of death (72%). Mortality was highest (56%) in perforations due to other primary pathology followed by NEC (53%). Overall mortality was 46%. CONCLUSION: It is essential to prevent secondary perforations by early recognition and management of primary pathology. Management of pneumoperitoneum in neonates with respiratory difficulties should be included in resuscitation before transfer. Rectal temperature monitoring and herbal enemas should be strongly discouraged.

Anti-Infective Agents↗
PubMed2002

Malignant solid tumours in neonates: an African perspective.

Malignant tumours in the neonate are distinct pathologically, clinically, and therapeutically from those in older children or adults. Behaviour cannot be directly implied from the histological appearance, and risk stratification is therefore difficult and complex. We review 42 patients seen over a 20-year period. Neuroblastoma (NB) was the commonest tumour seen (11), but the soft-tissue sarcomas were the dominant group (14). The initial management was surgical when possible. Chemotherapy, despite appropriate dose reduction, had significant morbidity and mortality. Whilst the outcome for congenital fibrosarcoma was good (6/7, 86%), there were no survivors amongst 5 patients with rhabdomyosarcoma. In the absence of cytogenetic and biochemical markers, risk stratification amongst babies with NB was based upon INSS staging. Stage I disease was associated with a good prognosis, whilst stage IV disease was uniformly fatal. Stage IVs disease had only 50% early survival. Patients with renal tumours, whether nephroblastoma or mesoblastic nephroma, did well. Only patients with morphologically immature teratomas were included, amongst whom there are 2 of 7 (29%) known survivors, but 43% have been lost to follow-up and their status is unknown. These figures are consistent with other reports from Africa.

Female↗
PubMed2002

Rectal gastric heterotopia in infancy.

Heterotopic gastric mucosa is rare in children with most cases presenting in association with Meckel's diverticulum. The authors present a 2-year-old boy with gastric heterotopia of the anorectum, who presented with painless, intermittent rectal bleeding.

Anus Diseases↗
PubMed2001

Internal drainage of pancreatic pseudocysts in children using an endoscopically-placed stent.

Persistent pseudocysts, which are rare in children, have traditionally been managed by open surgery. We describe two children who presented with large, established pseudocysts of the pancreas. They were successfully treated in the short term by minimally-invasive stent placement to create an internal cyst-gastric communication. This approach merits comparison with open surgical techniques.

Child↗