A comparison of national cancer registry and direct follow-up in the ascertainment of ovarian cancer

Completeness and accuracy of national cancer and death registration for outcome ascertainment in trials-an ovarian cancer exemplar

BACKGROUND

There is a trend to increasing use of routinely collected health data to ascertain outcome measures in trials. We report on the completeness and accuracy of national ovarian cancer and death registration in the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS).

METHODS

Of the 202,638 participants, 202,632 were successfully linked and followed through national cancer and death registries of Northern Ireland, Wales and England. Women with registrations of any of 19 pre-defined ICD-10 codes suggestive of tubo-ovarian cancer or notification of ovarian/tubal/peritoneal cancer from hospital episode statistics or trial sites were identified. Copies of hospital and primary care notes were retrieved and reviewed by an independent outcomes review committee. National registration of site and cause of death as ovarian/tubal/peritoneal cancer (C56/C57/C48) obtained up to 3 months after trial censorship was compared to that assigned by outcomes review (reference standard).

RESULTS

Outcome review was undertaken in 3110 women on whom notification was received between 2001 and 2014. Ovarian cancer was confirmed in 1324 of whom 1125 had a relevant cancer registration. Sensitivity and specificity of ovarian/tubal/peritoneal cancer registration were 85.0% (1125/1324; 95% CI 83.7-86.2%) and 94.0% (1679/1786; 95% CI 93.2-94.8%), respectively. Of 2041 death registrations reviewed, 681 were confirmed to have a tubo-ovarian cancer of whom 605 had relevant death registration. Sensitivity and specificity were 88.8% (605/681; 95% CI 86.4-91.2%) and 96.7% (1482/1533, 95% CI 95.8-97.6%), respectively. When multiple electronic health record sources were considered, sensitivity for cancer site increased to 91.1% (1206/1324, 95% CI 89.4-92.5%) and for cause of death 94.0% (640/681, 95% CI 91.9-95.5%). Of 1232 with cancer registration, 8.7% (107/1232) were wrongly designated as ovarian/tubal/peritoneal cancers by the registry and 4.0% (47/1172) of confirmed tubo-ovarian cancers were mis-registered. In 656 with death registrations, 7.8% (51/656) were wrongly assigned as due to ovarian/tubal/peritoneal cancers while 6.2% (40/645) of confirmed tubo-ovarian cancer deaths were mis-registered.

CONCLUSION

Follow-up of trial participants for tubo-ovarian cancer using national registry data will result in incomplete ascertainment, particularly of the site due in part to the latency of registration. This can be reduced by using other routinely collected data such as hospital episode statistics. Central adjudication by experts though resource intensive adds value by improving the accuracy of diagnoses.

TRIAL REGISTRATION

ISRCTN: ISRCTN22488978 . Registered on 6 April 2000.

The incidence of renal cancer in Polish National Cancer Registry: is there any epidemiological data we can rely on?

Introduction

The Polish National Cancer Registry (KRN) is the most commonly used sources of data on the incidence of cancers including renal cancer in Poland. Until today, the accuracy and completeness of these data has never been verified.

Material and methods

The aim of this study was to assess the completeness and reliability of data on the incidence of renal cancer published by the KRN. KRN data on newly diagnosed cases of renal cancer in Poland (for the whole country) and separately in subjectively selected provinces between 2009 and 2011 were retrospectively compared to the data received from the National Health Fund (NFZ) on the number of radical and partial nephrectomies performed due to renal cancer in the same time frame and regions.

Results

The concordance between the analysed two sources of data was 86%. Calculated ratio of the number of cases in the KRN database to number of cases in the NFZ database in selected provinces were as follows: 109% in Lubuskie, 60% in Mazowieckie, 123% in Podkarpackie and 66% in Podlaskie. No significant differences were observed between analyzed years (89% in 2009, 88% in 2010, 82% in 2011). The number of unreported cases of renal cancer in KRN was lower among male patients comparing to female patients (concordance: 78% vs. 72%).

Conclusions

The incidence of renal cancer published by KRN is underestimated, thus KRN does not seem to be a fully reliable source of epidemiological data. Due to the fact that this data is crucial for the planning of the health policy in Poland, improving urooncological reporting should be a priority for the health system managers.

Recruitment to multicentre trials--lessons from UKCTOCS: descriptive study

OBJECTIVE

To describe the factors that contributed to successful recruitment of more than 200,000 women to the UK Collaborative Trial of Ovarian Cancer Screening, one of the largest ever randomised controlled trials.

DESIGN

Descriptive study.

SETTING

13 NHS trusts in England, Wales, and Northern Ireland.

PARTICIPANTS

Postmenopausal women aged 50-74; exclusion criteria included ovarian malignancy, bilateral oophorectomy, increased risk of familial ovarian cancer, active non-ovarian malignancy, and participation in other ovarian cancer screening trials.

MAIN OUTCOME MEASURES

Achievement of target recruitment, acceptance rates of invitation, and recruitment rates.

RESULTS

The trial was set up in 13 centres with 27 adjoining local health authorities. The coordinating centre team was led by one of the senior investigators, who was closely involved in planning and day to day trial management. Of 1 243,282 women invited, 23.2% (288 955) replied that they were eligible and would like to participate. Of those sent appointments, 73.6% (205 090) attended for recruitment. The acceptance rate varied from 19% to 33% between trial centres. Measures to ensure target recruitment included named coordinating centre staff supporting and monitoring each centre, prompt identification and resolution of logistic problems, varying the volume of invitations by centre, using local non-attendance rates to determine the size of recruitment clinics, and organising large ad hoc clinics supported by coordinating centre staff. The trial randomised 202,638 women in 4.3 years.

CONCLUSIONS

Planning and trial management are as important as trial design and require equal attention from senior investigators. Successful recruitment needs constant monitoring by a committed proactive management team that is willing to explore individual solutions for different centres and use central resources to improve local recruitment. Automation of trial processes with web based trial management systems is crucial in large multicentre randomised controlled trials. Recruitment can be further enhanced by using information videos and group discussions. Trial registration Current Controlled Trials ISRCTN22488978.

Under-ascertainment of multiple myeloma among participants in UK atmospheric atomic and nuclear weapons tests

An inter-comparison of cases of multiple myeloma among UK participants in the UK's atmospheric atomic and nuclear weapons tests ascertained by direct follow up methods detected at least a third more cases than a strategy relying solely on data linkage between the Office of National Statistics and the Service Records Offices. These finding have implications for the conduct and robustness of follow up studies of long term health effects among participants in nuclear weapons tests.

Completeness and accuracy of registration of ovarian cancer in the cancer registry of Norway

Completeness of reporting and accuracy of the diagnosis of ovarian cancer from one health region in Norway to the Cancer Registry were examined. Data kept by the Cancer Registry were evaluated against discharge diagnosis data from all 8 hospitals in the health region during the period of 1987-1996. The assessment of the accuracy of the diagnosis recorded in the Cancer Registry was based on review of all medical records in the hospital setting and on slide review of all histologic diagnoses. The overall completeness of reporting ovarian cancer to the Cancer Registry was 99.6%. The organ specific completeness of registration of histologic verified ovarian cancer within the Cancer Registry was 95.3%; 0.9% was erroneously coded and 3.5% had their diagnosis changed to ovarian cancer at re-evaluation. Of all ovarian cancer cases registered at the Cancer Registry, 91% had a primary histologic diagnosis. Among 591 cases identified with a histologic diagnosis in the Cancer Registry, the accuracy of the diagnosis was estimated at 92%. Coding errors were found in 2% of these cases, while in 6% of the cases it was not possible to reproduce the original diagnosis of ovarian cancer at re-evaluation. In order to provide data of high quality for cancer surveillance a cancer registry needs several data providers, such as histopathologic laboratory reports and clinical reports. In addition, assessment of reported data through stringent quality assurance procedures within the registry are necessary for reaching a nearly 100% completeness of registration as found for ovarian cancer in the Cancer Registry of Norway.

How complete and accurate are cancer registrations notified by the National Health Service Central Register for England and Wales?

STUDY OBJECTIVE

To assess the completeness and accuracy of notification of cancers by the National Health Service Central Register (NHSCR) for England and Wales.

DESIGN

Comparison of 720 cancer registrations ascertained from NHSCR up to May 1999 with those ascertained for the same cohort from six other sources and a pathology review of the NHSCR cancer registrations.

PARTICIPANTS

People born in Cumbria, north west England, 1950-89, and diagnosed with cancer throughout the UK, 1971-1989.

MAIN RESULTS

Cancer diagnoses notified by NHSCR differed substantially from those determined by this pathology review for 47 of the 688 notified cases reviewed (7%; 95% CI 5%, 9%). Over one third of these discrepancies were attributable to failures in data capture or coding by the cancer registration system and almost half to changes in diagnosis; 26 of the 47 discrepant cases were reclassified as non-malignant and 21 as malignancies but with a substantially different diagnosis. The 694 confirmed malignancies represented 94% (95%CI 92%, 95%) of the 740 cancers ascertained from all sources.

CONCLUSIONS

It is estimated that the cancer registration system missed at least 10% (95%CI 6%, 15%) of all incident cases of malignant disease. Without additional ascertainment from multiple sources and diagnostic review, it would be incautious to use NHSCR cancer registrations as the sole basis of an epidemiological study.

Recent developments in ovarian cancer screening

There has been growing interest in the possibility of screening for ovarian cancer. This article addresses papers published following a systematic review of all prospective ovarian cancer screening studies since 1998. In the past year, new markers have been reported and previous strategies have been refined. A randomized controlled trial of ovarian cancer screening has shown a survival benefit in women who developed ovarian cancer in the screened group. Although the results do not justify ovarian cancer screening in the general population, the data support the need for a larger randomized trial powered to assess the impact of screening on mortality.

Performance of ultrasound as a second line test to serum CA125 in ovarian cancer screening

OBJECTIVE

To assess the performance of ultrasonography in a multimodal ovarian cancer screening strategy.

DESIGN

Prospective ovarian cancer screening trial between December 1986 and June 1993.

SETTING

General practice, occupational health departments and an ovarian cancer screening clinic at a London teaching hospital.

POPULATION

Postmenopausal women, > or = 45 years with a raised CA125.

METHODS

Volunteers with a CA125 > or = 30 U/mL underwent a pelvic ultrasound. Scans were classified as normal, abnormal (ovarian volume > or = 8.8 mL) or equivocal (normal volume with abnormal morphology). Abnormal ovarian morphology was subclassified as simple cyst (single, thin walled cyst with no septa or papillary projections) or complex (all other abnormalities). Volunteers with abnormal scans were referred for a gynaecological opinion. Follow up was via the cancer registry and postal questionnaires.

MAIN OUTCOME MEASURES

Sensitivity, specificity and positive predictive value of different ultrasound criteria for detection of index cancer (e.g. primary invasive epithelial carcinoma of the ovary and fallopian tube).

RESULTS

Seven hundred and forty-one women underwent 1,219 scans and 20 index cancers occurred during a median follow up of 6 x 8 years. The sensitivity for detection of ovarian cancer of different ultrasound criteria was 100% for abnormal morphology, 89 x 5% for abnormal volume and 84% for complex morphology. The highest specificity (97%) and positive predictive value (37 x 2%) was achieved using complex morphology.

CONCLUSION

A variety of ultrasound criteria can achieve high sensitivity, specificity and positive predictive value for index cancers in postmenopausal women with an elevated CA125. Use of ovarian morphology to interpret ultrasound may increase sensitivity and use of complex ovarian morphology may increase the positive predictive value.