Biomedical subjects

G Hunnam

Publications and source records attributed to G Hunnam.

5 recordsLinked to original sources

PubMed2005

Audit of negative assessments in a breast-screening programme in women who later develop breast cancer-implications for survival.

The aim of this study was to examine observed short-term survival, to estimate future survival, and to assess the impact on survival of amending procedures to avoid false negatives in women recalled for further assessment due to a suspicious screening mammogram. From the start of screening in the seven centres in the East Anglian region, 1 April 1989 to 31 December 1999, 503493 women from a total population of 2.2 million were screened, 25346 were recalled for an assessment and 3689 were diagnosed with breast cancer. Of the 21657 women given a negative result at these assessments, 193 women were subsequently diagnosed with 194 breast tumours at the site previously assessed. These women were followed up for survival, with survival analysis adjusting for host and tumour attributes. We also predicted long-term survival using the pathological features of the tumours diagnosed. From previous estimates of tumour progression rates, we estimated the reduction in incidence of advanced tumours and the potential saving of lives had unsatisfactory assessments been carried out within guidelines. There were 17 deaths, 15 in women who had unsatisfactory assessments. Five-year survival was estimated at 93% (95% CI: 88-97%) for breast cancer and 91% (95% CI: 86-95%) for all cause deaths. Women with positive nodes and/or larger tumours had significantly worse survival. Twenty years survival for women with unsatisfactory assessments was estimated at 66% (35 deaths) and predicted a potential saving of 7-9 lives (14-18% reduction in expected fatality within this special tumour population) had original assessments been carried out within current guidelines. This retrospective audit of a small and special tumour population shows a potential reduction in breast cancer deaths of 18%, had current guidelines been available for the original assessments. Increased use of percutaneous biopsy in recent years should address the problem.

Breast Neoplasms↗

PubMed2004

An audit of assessment procedures in women who develop breast cancer after a negative result.

OBJECTIVES: A case audit was undertaken to determine the extent to which the early diagnosis of cancer could be improved by better adherence to screening guidelines, and to estimate the effect that this might have on breast cancer survival. Although affecting only a small proportion of the cancers of the screening programme, this exercise had an educational function for screening radiologists. SETTING: The East Anglian breast screening programme, a group of seven centres offering screening to a total population of 2.2 million inhabitants. Women were screened every three years between the ages of 50 and 64. METHODS: Adherence to the guidelines of the UK National Breast Screening Programme (as published in 2001) was tested in women assessed between the start of screening on 1 April 1989 and 31 December 1999, in cases where the screen was negative but who were subsequently diagnosed with breast cancer. RESULTS: In this period the programme screened 503,493 women, recalled 25,346 and diagnosed 3689 with cancer. 194 cancers in 193 women were reviewed, comprising those cancers that arose at the site of the lesion previously assessed. 96 women (49.5%) had calcifications, 48 (24.7%) had opacities. 139 of 194 cases were judged to have been inadequately assessed. A recurring theme showed that biopsies not undertaken or with false negative findings led to failure to diagnose lesions which were subsequently shown to be cancer. Microcalcifications and opacities were more likely to have been inadequately assessed than spiculate masses, parenchymal deformities, or asymmetric densities. In the earliest time period (1989-1993), there were a larger proportion of inadequately assessed cases than in the period 1994-1999. CONCLUSION: Scrupulous adherence to good guidelines will result in a greater proportion of cancers being diagnosed. Failure to perform effective percutaneous biopsy was the usual cause of missed diagnoses. Although an infrequent occurrence this may have an effect on subsequent survival from breast cancer.

Adolescent↗

PubMed2001

Interval cancer peer review in East Anglia: implications for monitoring doctors as well as the NHS breast screening programme.

AIM: To devise a method for reviewing interval cancers that will both educate radiologists and facilitate improvement of breast screening practice. To evaluate different methods for case classification to find one that best serves this purpose. METHOD: The method of peer review and the means by which interval cancers are classified is described. The way in which cases are designated false-negative is an issue of acceptability for radiologists, and so three different methods are evaluated. Each is applied to the data set collected in this region over a 3-year period. RESULTS: For cases read by five readers, when a consensus method was used for classifying cases, the proportion of cases classified as false-negative was 14%. Using a method in which only one of the five readers had to classify a case as false-negative for it to be categorized as such, the proportion of false-negative cases rose to a maximum of 38%. The minimum proportion of cases that could be considered to be false-negative was 6% and was obtained when all five readers had to classify a case as false-negative for it to be so categorized. Consistent with its majority viewpoint, the consensus method gave results for proportions of total cases classified as false-negative which were similar to those given by methods in which cases are classified as false-negative if either three of five readers, or at least 60% of readers, classified it as such. CONCLUSION: For the peer review method to achieve its dual aims of educating radiologists and auditing performance, the participating radiologists must share ownership of the results and view the analysis as fair. The method used to classify interval cancers as false-negative will influence the number so classified. A consensus method has been found to give a result that is both fair and acceptable to our radiologist. Using this method 16% of all reviewed cases were classified as false-negative and 60% as true interval cancers. Britton, P. D. (2001). Clinical Radiology56, 44-49.

Breast Neoplasms↗

PubMed2001

Radiological peer review of interval cancers in the East Anglian breast screening programme: what are we missing? East Anglian Breast Screening Programme.

OBJECTIVE: To determine whether association between classification of interval cancers (false negative, minimal sign, true interval, occult) and tumour characteristics can indicate areas for improvement in effectiveness of screening. SETTING: East Anglian regional Breast: Screening Programme. METHOD: The consensus classification of interval cases, obtained through peer review, was compared with tumour characteristics: size; grade; and nodal status, and with radiological signs. A set of 923 cancers with known tumour characteristics, presenting in unscreened women, was available for comparison. RESULT: In total, 385 interval cases were analysed. Prognosis of interval cancers was at least as good as that of cancers in unscreened women, with fewer node positive cases. No significant relation was found between classification of cases and age of patients. True intervals tended to present later after a negative screen, although false negatives commonly presented earlier. Occult cancers were significantly smaller than false negatives. Analysis of histological type yielded little of relevance, and mammographic appearance was similar in all classifications. At diagnosis, cancers in the low risk group were more likely to be seen as spiculate masses, whereas high risk cases more often appeared as opacities. A higher proportion of interval cases had been assessed than in the normal screened population. CONCLUSION: Sensitivity may be improved by reducing false negative and minimal sign cases (21% of interval cancers in East Anglia). These will include tumours in all risk groups, and with all radiological features, thus no particular age group or radiological feature may be targeted for improvement. Misdiagnosis at assessment reduces sensitivity and therefore merits particular study.

Aged↗

PubMed1994

Radiology workload--a solution reviewed after 14 years' experience.

A method of controlling the radiological workload in a district general hospital, based on an estimation of the reasonable capacity of the department, was introduced in 1978. Measurement of the number of examinations performed compared with the estimated reasonable capacity shows that the method has been effective. An immediate 25% reduction in examinations was followed by a workload which varied between -4% and +16% of the capacity. An increase in the proportion of complex examinations in the period under review has been recognized. The method has encouraged referring doctors to exercise restraint and adopt guidelines, and helped persuade managers to increase capacity by appointing additional radiologists.

Appointments and Schedules↗