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K R Muir

Publications and source records attributed to K R Muir.

50 records · Page 3Linked to original sources
PubMed1993

Neuroblastoma: a 32-year population-based study--implications for screening.

This paper describes a retrospective population-based study of neuroblastoma in the West Midlands Health Authority Region--childhood population 1.12 million (OPCS, census 1981)--in which 239 cases were diagnosed between 1st January 1957 and 31st December 1988. The age standardised rate of tumour incidence has remained constant at 7.2 cases per million children per year. The median age at diagnosis was 2 years with 18% of children presenting before the age of 6 months. Fifty children (21%) presented before the age of one year, and for this group of children, the prognosis has improved significantly over the 32-year period (10 year survival increasing from 63% in 1957-67 to 87% in 1978-88), whereas for the 189 (79%) children who presented after one year of age, the prognosis has remained very poor during the study period (10 year survival 1957-67 = 9.5%, 1978-88 = 8.5%). This study supports the need for a prospective study of mass screening at several intervals rather than only at 6 months of age.

Abdominal Neoplasms↗
PubMed1993

Malignant epithelial tumours in children: incidence and aetiology.

The purpose of this study was to establish the incidence of carcinomas in children, changes in incidence over a 30-year period, and to identify features of possible aetiological significance. A total of 173 cases were identified, but after review of the histopathology, 30 patients were excluded because they were considered to have benign epithelial tumours or malignant tumours of nonepithelial origin. Seven other cases were excluded because pathology material was not available. Overall, in 28% of cases, the diagnoses were changed by pathology review. Thus, 136 children in the West Midlands Region diagnosed 1957-1986 were included, with carcinoid tumours (44) and tumours of skin (22), nasopharynx (14), salivary gland (13), adrenal cortex (13), thyroid (9), large bowel (5), other (16). Excluding carcinoids, the age-standardised incidence rate was 2.4 x 10(6) per year. Male:female ratio was 0.7:1 and 66% were aged > 10 years. Incidence increased from 1.5 to 3.3 x 10(6) per year. Genetic factors predisposing to carcinoma included tyrosinosis, MEN II and III, congenital adrenal hyperplasia and basal cell naevus syndrome. There was a case of Li-Fraumeni syndrome and several other patients had relevant family histories. Probable "environmental" causes included antenatal exposure to stilboestrol or hydroxyprogesterone hexanoate, stilboestrol given for premature menarche, neonatal hepatitis and prior radiotherapy. The aetiology of carcinomas in children is multifactorial, both genetic and environmental factors being important. The incidence is increasing.

Adolescent↗
PubMed1993

Retrospective study of prognostic value of DNA ploidy and proliferative activity in neuroblastoma.

AIM: To assess the prognostic value of age and stage at diagnosis, site of primary tumour, cell ploidy and N-myc copy number in children with neuroblastoma. METHODS: Flow cytometry was used to determine the cellular DNA content of paraffin wax embedded archival material from 69 cases of neuroblastoma and was successful in 52. RESULTS: The age, stage, and survival distribution of the sampled cases was not significantly different from that in a larger population based series. There were seven diploid ("non-aneuploid") and 45 aneuploid (including two tetraploid and four triploid) tumours. The 10 year survival was significantly better for cases of aneuploid rather than diploid tumours (p < 0.05). An important new finding was that 10 year survival was also significantly better for tumours with a low percentage of cells in S phase (p < 0.03). CONCLUSION: The percentage of cells in S phase, a measure of the proliferative activity of the tumour, correlated with prognosis in neuroblastoma. This should be measured with other biological features of the disease, such as N-myc copy number, when prognostic indicators are being assessed.

Adolescent↗
PubMed1992

Childhood cancer in the West Midlands: incidence and survival, 1980-1984, in a multi-ethnic population.

The purpose of this study is to describe the incidence and survival of childhood cancer in the West Midlands for the period 1980-1984. Proportional breakdown by Asian subgroup is also considered. A total of 587 patients were registered, 49 of them of Asian origin. Breakdown to Asian versus non-Asian subgroups by diagnosis revealed comparatively high rates for Hodgkin's disease, retinoblastoma and neuroblastoma in the Asian patients. However, a deficit of cases was seen for CNS tumours. Comparison of overall age-standardized rates (ASR) for all cancers revealed a substantially lower value compared to that reported for the USA white population but a similar value to the USA black and UK white populations. Diagnostic breakdown revealed that the major difference between the West Midlands Regional Children's Tumour Research Group (WMRCTRG) and the USA white ASR was in the leukaemia and lymphoma group. Overall survival for the series was 56% at 5 years. The poorest prognosis was found in acute myeloid leukaemia, with only 23% of patients surviving at 5 years, against 62% in acute lymphoblastic leukaemia. CNS tumours also had a poor outcome, with an overall survival rate of 47%, although certain individual diagnoses were more favourable. We observed a 100% survival rate in Hodgkin's disease up to 5 years from diagnosis, and both Wilms' tumour and retinoblastoma had 90% survival rates.

Adolescent↗
PubMed1992

A geostatistical approach to the analysis of pattern in rare disease.

The incidences of human disease vary from place to place, and some show distinct patterns. Patterns in rare diseases, such as childhood cancer, are not readily discernible, however, and this makes it difficult to relate their distribution to factors in the environment in seeking possible causes of the disease. Provided cases are geographically indexed, data on a disease can be analysed geostatistically. Variograms can be computed to determine the strength and spatial scale of any pattern, and to summarize the variation, and then the risk of developing the disease can be estimated by kriging. This has been done for the incidence rates of childhood cancer from 1980 to 1984 in the West Midlands Health Authority Region of England. A novel modification was made to compute the variogram of the risk from that of the frequencies, taking into account the binomial nature of the data. The incidence of the disease appears patchy. The results show that this patchiness is spatially correlated and not purely random. The risk appears greatest in the rural south west of the Region and in some of the suburbs around the conurbation. This approach using geostatistics seems very promising and will be developed further as more data for this and other diseases become available.

Child↗
PubMed1991

Descriptive epidemiology of primary central nervous system tumours in children: a population-based study.

This study was undertaken to investigate the incidence, outcome and referral patterns of central nervous system tumours in a defined childhood population over a recent 5-year period. The study incorporated pathological review of all available diagnostic material and follow-up assessed survival at a minimum of 5 years from diagnosis. One hundred and forty-seven cases were reviewed, representing an annual incidence of 26.5 per million children aged less than 15 years. The distribution of individual diagnoses by age, sex and anatomical site was similar to comparable data collected previously in the United Kingdom and North America, but the inclusion of 28 cases (19%) without biopsy suggested that the wider use of computed tomography might account for a small increase in incidence over previous estimates. Analysis of referral to the Regional Paediatric Oncology Unit showed that the patients referred were younger than those not referred and were over-represented amongst the diagnoses of medulloblastoma, ependymoma and brain stem glioma, which carry the worst prognosis. Survival for all diagnoses together was 51% at 5 years, ranging from 13% for unbiopsied brain stem gliomas to 100% for juvenile astrocytomas. Referral to the Regional Unit appeared to have some survival advantage for children with medulloblastoma, although this was not statistically significant. Accurately reviewed data such as these are essential in order to assess current workload and treatment success, in addition to enabling investigation of future diagnostic and treatment strategies.

Adolescent↗
PubMed1991

Congenital mesoblastic nephroma: possible prognostic and management value of assessing DNA content.

The case records and pathology of all children with kidney tumours treated in the West Midlands Health Authority Region (WMHAR) from 1957 to 1986 were reviewed. The histology was reviewed by a panel of three paediatric pathologists. Thirteen (6%) out of 211 cases were considered to have congenital mesoblastic nephroma (CMN). Nine were of the conventional type, three of the atypical cellular type, and one mixed. DNA ploidy was investigated and showed two of the tumours to be aneuploid and nine diploid (tissue was not available in the two other cases). The two aneuploid tumours were of atypical cellular and mixed histology, respectively; the diploid tumours were of the conventional type in eight cases and atypical cellular in one. The atypical cellular type has been reported to behave more aggressively, but the benefit of additional treatment after surgery to prevent recurrence remains unclear. Measurement of DNA content by flow cytometry, together with histological subclassification, may be useful in selecting patients who will benefit from further treatment after surgery.

DNA, Neoplasm↗
PubMed1990

'Clustering'--real or apparent? Probability maps of childhood cancer in the West Midlands Health Authority region.

The West Midlands Regional Children's Tumour Registry collects detailed information on all cases of childhood cancer in the West Midlands Health Authority Region (WMHAR). The distribution by electoral ward of all cases diagnosed in the WMHAR between 1980 and 1984 has been determined. Analysis has also been performed for leukaemias/non-Hodgkin's lymphomas alone. We suggest that this latter grouping should be universally employed, owing to the difficulty of accurately separating out cases of leukaemia. Both spatial analyses showed several wards with significantly excessive rates on the basis of their cumulative Poison probability. Observed/expected ratios of 3-35 were seen for cases in significant wards, which are similar to the ratios seen in analysis of incidence around nuclear installations. However, further detailed consideration of these individual significance levels in the light of the number of statistically significant wards which would occur by chance alone, due to the multiple use of the test, accounted completely for the number of wards obtained in each of the groups considered. Thus, apparent 'clustering' of cases could be mere statistical artefact. In the WMHAR, therefore, using the technique of probability mapping, no true spatial pattern of incidence was found, other than that which would occur by chance alone. This, in a large area without nuclear installations and an even mix of rural and industrialised regions, could be seen as control data for those studies which have considered cases of childhood leukaemia around nuclear facilities, where the observation of single point clusters associated with suspected sites restricts assessments of spatial pattern in the rest of the area.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Malignant hepatic tumours in children: incidence, clinical features and aetiology.

Congenital defects and other disorders have been reported in association with malignant liver tumours. In order to assess their significance, a population-based survey was undertaken on children aged less than 15 years diagnosed with malignant liver tumours during the 30 years 1957-1986. The cases were identified from information collected by the West Midlands Regional Children's Tumour Registry. Pertinent data were extracted from their clinical records, and the original biopsy and any necropsy material were reviewed by a panel of three paediatric pathologists. Of the 50 eligible cases registered, eight were excluded because histology review showed that they had non-malignant conditions (3) or malignancies of extrahepatic origin (4) or because no pathological material was available (1). The diagnoses in the remaining 42 cases were hepatoblastoma (27), hepatocellular carcinoma (3), rhabdomyosarcoma (6), rhabdoid tumour (3) and yolk sac tumour (3). The incidence of primary malignant liver tumours was 1.20 per 10(6) person years and that of the hepatoblastoma sub-group was 0.77 (average childhood population of the West Midlands for the time period being 1,166,500). The presenting clinical, radiological and biochemical features were similar to those reported in other series and the ethnic and social class distributions were unremarkable compared with the local population. Congenital defects or other possibly related features were present in nine (21%) patients. Our results, taken with other reports, suggest that hepatoblastoma is a malignant tumour related to maldevelopment, possibly associated with 11p or 5q mutations, whereas hepatocellular carcinoma is more usually a complication of metabolic and other disorders which lead to cirrhosis.

Child↗
PubMedDate not supplied

Hodgkin's disease in children in the West Midlands, 1957-1986: a large population-based study.

One hundred forty-one children were diagnosed with Hodgkin's disease between 1957 and 1986 in the West Midlands Health Authority Region (1991 population, 1.1 million children). Eighty-seven were boys and 54 were girls, representing a significant male:female ratio of 1.5:1 (P < 0.01). The average age-standardized incidence rate was 3.6 per million per year with a significant increase in the older age group (> or = 10 years) in the second half of the period (P = 0.02). The mixed cellularity subtype was more common in those younger than 10 years, with nodular sclerosing disease being seen more in those < or = 10 years. Overall survival at 5 years was 76% (65% at 10 years) with a significant difference (P < 0.001) in survival between the first and last decades. There was six second malignancies, five of which could have been treatment related. A positive history of cancer in close relatives was found in 11 patients, and higher social class was found in more older than younger children. These findings support the hypothesis that Hodgkin's disease may have a viral etiology and may be linked with socioeconomic conditions.

Actuarial Analysis↗
PubMedDate not supplied

Analysis of ploidy and proliferative activity in childhood non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD).

We have performed DNA analysis by means of fluorescence-activated cell cytometry on paraffin-embedded tissue from the diagnostic biopsy specimens in 40 cases of non-Hodgkin's lymphoma (NHL) and 25 of Hodgkin's disease (HD) and from 50 normal tonsils as controls. For HD cases, aneuploidy was found in 7 of 25 (28%), a higher proportion than in two previous studies of mainly adult patients. Diploid tumors showed S-phase fractions (SPFs) similar to those of controls. In the NHL cases aneuploidy was found in 12 of 40 (30%) with no significant association with site, stage, histopathology, immunophenotype, or prognosis. SPFs were highest in abdominal and chest primary sites but were not related to stage. Burkitt's lymphomas had the highest SPFs relative to lymphoblastic (P < .01) and centroblastic lymphomas (P < .05). Significantly higher SPFs were found in B cell than in T cell tumors (P < .001). There was considerable heterogeneity for SPFs within each NHL subgroup. Survival was worse at 5 years for those with high SPFs compared with those with normal SPFs (P = .04). These results suggest that tumor DNA analysis may be useful in the evaluation of children with NHL. Larger studies are needed to define its role as an independent prognostic variable.

Aneuploidy↗