Concordance on the recording of cancer in the Saskatchewan Cancer Agency Registry, hospital charts and death registrations

Accurate and complete registries are an important source of knowledge about cancer. The concordance of the recording of neoplasms in the Saskatchewan cancer registry with that in hospital charts and death registrations was evaluated for 368 patients. The agreement between registry and hospital charts or death registrations was excellent (kappa: 0.93; 95% confidence interval: 0.89, 0.97), with 91.3% of those with cancer having the same neoplasm recorded in their chart or death registration as in the registry. There was only one patient whose hospital chart indicated cancer who was not in the registry and one apparent major discrepancy relating to the cancer site, which was due to the recording of the primary site in the registry and a secondary in the hospital chart. Although based on a relatively small number of patients, these results suggest a high degree of consistency between cancer registry, hospital charts and death registrations in Saskatchewan.     

Management of colorectal cancer in three south Thames District Health Authorities

This study describes the management of colorectal cancer, diagnosed in 1988, of residents in three South Thames Districts.Of the 328 cases identified as having being diagnosed in 1988, case notes were retrieved on 263 (80%) including 62 registered by death certificate only. There were 159 cases (61%) of colon cancer and 104 cases (39%) of rectal cancer. Of these, 172 cases (68%) were admitted electively and 90 (32%) as emergencies. Patients subsequently diagnosed with colon cancer had a relative risk of being admitted through emergency (relative to rectal cancer patients) of 1.39 (95% C.I.: 1.16, 1.67). Elective admissions varied significantly by district of residence (P < 0.0001) ranging from 36–65% for colon cancers and from 63–92% for rectal cancers across the three districts. Dukes' stage was recorded in only 143 (54%) sets of case notes, with significant variation by district of residence in the proportion of elective patients for whom a Dukes' stage was indicated (P < 0.01).Two-hundred and thirty-six (90%) cases received treatment. Of the treated cases, 233 patients received surgery with 29 cases of colon cancer (18%) and 32 cases of rectal cancer (31%) receiving adjuvant therapy. The proportions of anterior resection, AP resection and colostomies given, varied by district. Patients presenting for elective surgery were more likely to be treated by a consultant than patients presenting on emergency: the relative risks were 2.58 (95% C.I.: 1.74, 3.82) for colon cancer patients and 4.93 (95% C.I.: 2.20, 11.06) for rectal cancer patients. In 44 (26%) colon cancer cases and 21 (22%) rectal cancer cases it was explicitly stated that the tumour had not been fully resected.For colon tumours the five year relative survival rates were 35% (95% C.I.: 21%, 50%), 52% (95% C.I.: 34%, 70%), and 14% (95% C.I.: −2%, 30%) in districts A, B and C respectively. The corresponding figures for rectal tumours were 45% (95% C.I.: 27%, 64%), 62% (95% C.I.: 41%, 83%) and 24% (95% C.I.: −1%, 50%).There were wide variations in the representation, management of and survival from colorectal cancers across the three districts. Differences were significant at the level of district of residence, mode of presentation and surgical grade. More assiduous recording of Dukes' stage is imperative if consensus is to be achieved on effective management. Further work is also warranted on district differences in diagnostic and referral protocols.     

Incompleteness and retrieval of case notes in a case note audit of colorectal cancer.

Hospital case notes are a crucial source of data but are subject to two major biases: incompleteness of data and non-retrieval. To assess these biases in relation to colorectal cancer a study was performed of all cases of colorectal cancer listed in the Thames cancer registry in patients resident in one of four districts in South Thames regions with a diagnosis in 1988. Five medical record sites were involved. Retrieval rate for all case notes for districts combined was 80%. In two districts the rates were too high for further investigation; in the other two respectively patient survival and whether treatment was given were positively associated with retrieval. Among the four districts incompleteness of notes ranged from 38% to 62% for staging, 8% to 40% for treatment, and 70% to 25% for diagnostic tests. Information about treatment was missing in 3% to 20%; survival data were omitted in less than 5%. In all districts completeness of case notes was inadequate and in some non-retrieval compounded the problem. Missing data reduce the quality of cancer registry data and potentially undermine interpretation of epidemiological studies and evaluation of care. Further research is warranted into the standards and resourcing of medical records departments and their effects on retrieval and data quality. Structured proformas could be applied across specialties to identify missing items in case notes, to identify areas where standards are required, or to audit notes where standards have already been agreed. A staging protocol to set standards for colorectal cancer has been adopted in one district, and a prospective audit is being established.     

Influence of "diagnostic delay" upon cancer survival: an analysis of five tumour sites.

STUDY OBJECTIVE--The aim was to assess the relationship between survival, tumour stage, and the interval from first symptom to diagnosis (SDI, or duration of symptoms). DESIGN--This was a retrospective follow up study of a cohort of patients registered in the tumour registry of the Hospital del Mar (Barcelona). SETTING--Hospital based tumour registry, with patients derived mainly from the City of Barcelona. PARTICIPANTS--1247 cases of lung, breast, stomach, colon, or rectal cancer were analysed using survival curves and Cox proportional hazards regression. Subjects (mean age 63.6 years) were followed for a median length of 12.9 months after diagnosis. At the time of diagnosis one fourth of patients had disseminated disease. MEASUREMENTS AND MAIN RESULTS--Based on clinical records, a physician registered the onset time of the first symptom attributable to cancer (from which the SDI is computed), as well as the tumour stage at diagnosis. Other measurements followed standard tumour registry procedures. Overall, the crude mean SDI was 5.15 months (SD 8.03, median 2.03); only 24.5% of cases had an SDI less than a month. Crude mean SDIs by anatomical site were as follows: lung cancer 3.07 months; breast 7.44; stomach 5.34; colon 5.74; rectum 5.03. Tumour extension did not appear to be significantly influenced by SDI, only breast cancer showing a distinct pattern of increased extension with increasing SDI. As expected, the probability of survival decreased monotonically with increasing stage in all sites. Tumour site was also a significant predictor of survival, which at one year ranged from 93% for breast cancer to 28% for lung cancer. However, a longer SDI tended sometimes to be associated with a better chance of survival, a fact that was most apparent in colon cancer. All Cox proportional hazards models showed a consistent picture: SDI was not a significant predictor of survival (age and sex adjusted hazard ratios ranging from 0.97 to 1.01), neither was sex; age did predict survival, and so did site and stage. CONCLUSIONS--The results provide further evidence of a very weak relationship between SDI and tumour stage at diagnosis (except for breast cancer), and between SDI and survival, thus emphasising some limitations within which early clinical detection operates. They also suggest that in addition to reflecting patient and physician behaviour, as well as the functioning of the health system, SDI may be influenced by the biological behaviour of the tumour.     

Completeness of case ascertainment in a Scottish regional cancer registry for the year 1992

To assess completeness of case ascertainment by the Scottish Cancer Registry for the year 1992, we assembled a collection of databases containing potential registrations (excluding non-melanoma skin tumours and non-invasive neoplasms) from 14 separate sources relating to the population covered by one of the five regional registries. Apparently missed registrations were identified by linkage of these databases to cancer registration records. Their eligibility for registration was determined by reference to medical records, or when these were unavailable, by reference to the local Community Health Index (to establish residency at the time of diagnosis) in conjunction with the text of the original pathology report and/or the original death certificate. Misclassifications of site or incidence year were not regarded as missed cases.Of 517 apparently missed cancer registrations, 66 cases (3.5% of the revised total number of registrations of malignant neoplasms other than non-melanoma skin tumours for the study area in 1992) should have been registered as new independent primary malignant neoplasms, giving an overall estimate of completeness of 96.5%. The fact that so many apparently missed registrations were not eligible for registration illustrates the limitations of passive registration. Ascertainment of cases by the Scottish Cancer Registry appears to be high for most sites and compares favourably to the figures reported by registries outside Scotland.     

Risk of breast cancer after miscarriage or induced abortion: a Scottish record linkage case-control study

STUDY OBJECTIVE: To assess the risk of breast cancer in patients with a previous history of miscarriage or induced abortion. DESIGN: Case-control study relating "exposure" to outcome by linkage of national hospital discharge and maternity records, the national cancer registry, and death records. SETTING: Scotland. PARTICIPANTS: Miscarriage analysis-2828 women with breast cancer and 9781 matched controls; induced abortion analysis-2833 women with breast cancer and 9888 matched controls. MAIN RESULTS: After stratification for age at diagnosis, parity, and age at first birth, the odds ratio (95% confidence intervals) of breast cancer was 1.02 (0.88 to 1.18) in women with a previous miscarriage, and 0.80 (0.72 to 0.89) in women with a previous induced abortion. Further adjustments for age at bilateral oophorectomy, socioeconomic status (based on small area of residence), and health board area of residence had only minor effects on these odds ratios. CONCLUSION: These data do not support the hypothesis that miscarriage or induced abortion represent substantive risk factors for the future development of breast cancer.     

The effect of socioeconomic status on survival from colorectal cancer in the Melbourne Collaborative Cohort Study

Previous research relating lower socioeconomic status (SES) with poorer survival from colorectal cancer has varied in adjustment for confounding factors and in the use of individual-level or aggregate-level indicators of SES. We investigated the effect of SES and country of birth on survival from colorectal cancers diagnosed in participants of the Melbourne Collaborative Cohort Study. A total of 526 colorectal cancer cases diagnosed since baseline were followed from diagnosis to 1 June 2006 or death. Information on tumour site and stage, and treatments given were obtained from systematic medical record review. SES at diagnosis was assigned using both an area-based measure of social disadvantage and individual level of educational attainment. Cox regression models were used to estimate hazard ratios associated with socioeconomic disadvantage, educational attainment, and country of birth. During an average follow-up of 5.6 years from diagnosis, 230 deaths occurred, 197 from colorectal cancer. After adjusting for age, sex, tumour stage, waist circumference and adjuvant chemotherapy and radiotherapy, the hazard ratios of dying from all causes and from colorectal cancer associated with living in the least disadvantaged areas compared with most disadvantaged areas were 0.73 (95% CI 0.53–1.00, p for trend = 0.06) and 0.80 (95% CI 0.57–1.12, p for trend = 0.22) respectively. Further adjustment for hospital case-load, tumour characteristics, and lifestyle factors did not change the estimates materially. Level of educational attainment and country of birth were not independent predictors of the risk of dying from colorectal cancer. Despite a universal health care system in Australia, socioeconomic inequalities in survival from colorectal cancer exist, and an enduring challenge is to ensure that improvements in colorectal cancer survival are shared equally across the population.     

An example of record linkage methods to monitor mortality and cancer incidence

Linkage of New York State record systems was the key strategy in a restrospective cohort study with a 24–34 year followup interval. Parents of children with anencephaly or spina bifida and matched control parents were traced to determine the parents'' cancer and death experience. Birth certificates for Upstate New York for 1945–55 were the source of the study groups. This report describes the methodology employed. The New York State Health Department''s Cancer Registry and vital records, the State motor vehicle license files, and city and phone directories were searched for the most recent record indicating residence in Upstate New York, cancer incidence, or death.Among the parents of the 1,152 index children were 18,571 person-years of followup for mothers and 21,675 person-years for fathers. Among the 1,152 controls, there were 19,682 person-years of followup for mothers and 22,596 person-years for fathers. Although losses were larger than the optimal, a large proportion of the maximum possible person-years were obtained, regardless of the birth year of the index child. Patterns of loss to followup were similar for cases and controls.Record linkage techniques are especially applicable in followup studies if the risk factor is identifiiable from routinely collected information (for example, congenital neural tube defects listed on birth certificates) and the outcome is also identifiable from such records (for example, cancer registry certificate or death certificate). If the outcome is definitive, reported routinely and comprehensively, and stored on a machine-readable medium, use of a computerized record linkage design is very efficient. A major advantage of the design is that cases and controls are treated equally with respect to outcome ascertainment and followup, so that some potential biases are eliminated. Finally, the method is non-intrusive; the subjects are never contacted or interviewed. Strictly maintained confidentiality is, of course, required.     

Cancer identification using a tumor registry versus death certificates in occupational cohort studies in the United States.

Studies of cancer incidences among occupational cohorts are rarely performed in the United States because of incomplete registration and a limited time period available for follow-up. This study used data from concurrent studies of cancer mortality and incidence among a cohort of 4,528 fire fighters and police officers employed by the cities of Seattle and Tacoma, Washington, between 1944 and 1979 to examine the relative advantages of tumor registry and death certificate information. As expected, an increased ability to study relatively common cancers with low fatality rates was demonstrated using incidence data. The most dramatic example was seen for bladder cancer. Twenty-four bladder cancers had been diagnosed among the study cohort between 1974 and 1989, whereas only two deaths were attributed to this malignancy. The standardized incidence ratio for bladder cancer was 1.05 (95% confidence interval 0.67-1.55), whereas the corresponding standardized mortality ratio was 0.46 (95% confidence interval 0.05-1.65). The observed relative risk estimates for rapidly fatal cancers were similar using the two sources of information, and no increase in precision was observed. Of 142 persons in the registry area who died of cancer during the study period, 20 (14%) had a different site listed on the death certificate than was identified by the registry. Approximately 7% of the potential person-years of follow-up were lost due to migration out of the registry area; loss to follow-up was greater among older and short-term workers, but did not exceed 13% of the person-years. Population-based tumor registries can be a useful resource in the investigation of occupational cancer in the United States, especially for the study of cancers with high survival rates.     

Accuracy of cancer registration.

In South Wales cancer registration is done principally by means of the Hospital Activity Analysis. Altogether 1460 hospital records of cancer patients (19% of the 1972 registrations received by May 1973) were studied and the principal items of information required for cancer registrations by the Office of Population Censuses and Surveys were copied and subsequently compared with the corresponding registrations at the Welsh Hospital Board''s cancer bureau. Differences between these ''re-registrations'' and the original registrations were analysed item by item. There were 234 registrations with errors in the diagnostic summary (although 110 of these would cause misclassification only under the fourth digit of the ICD code), 164 with errors in date of birth (36 of which would cause classification in the wrong WHO age group) and 198 with errors in the date of registration (112 of which were wrongly ascribed to the year 1972). Error and omission rates were particularly high for NHS number, occupation, place of birth, and histology.     

Selected cancer mortality and farm practices in Iowa

Death certificate analyses of white male Iowans over age 30 who died of multiple myeloma, non-Hodgkin's lymphoma, prostate cancer or stomach cancer between 1964 and 1978 were completed. Each case was matched to two controls on age (within two years) at death, county of residence, and year of death. Consideration of usual occupation, as recorded on the death certificate, resulted in the following odds ratios for mortality due to the specified cancers among farmers: multiple myeloma, 1.48; non-Hodgkin's lymphoma, 1.26; prostate cancer, 1.19; and stomach cancer, 1.32. Each is statistically significant (p less than 0.05). Odds ratios were computed separately for three birth cohorts according to counties stratified by crop and livestock production. Multiple myeloma was elevated in those born after 1890 and was associated with number of egg-laying chickens, hog production, insecticide use, and herbicide use. Non-Hodgkin's lymphoma was elevated in those born before 1901 and was associated with egg-laying chickens, milk products sold, hog production, and herbicide use. Although prostate cancer was elevated in those born before 1901, it was not associated with any agricultural practice. Stomach cancer was elevated in each birth cohort. It was associated with milk products sold, cattle production, and corn per acre.     

Monitoring the impact of human papillomavirus vaccines on high-grade pre-invasive cervical lesions: Designing a framework of linked immunization information system and cancer registry data in Michigan

State immunization and cancer registries contain data that, if linked, could be used to monitor the impact of human papillomavirus (HPV) vaccine on cervical cancer and precancer. Michigan is uniquely positioned to examine these outcomes using two population-based resources: the state-wide cancer registry and immunization information system (IIS).We assessed the feasibility of identifying females in the IIS who had continuous Michigan residence and linking them to the cancer registry. We considered continuous residence necessary for future studies of vaccine impact to avoid misclassifying those who may have been immunized while residing out-of-state and whose immunization therefore may not have been reported in Michigan.We identified females with 1976–1996 birthdates in the IIS and used probabilistic linkage software to match them with Michigan birth records. A stratified random sample of IIS-birth matches was provided to a commercial locator service to identify females with continuous Michigan residence. Cervical carcinoma in situ cases diagnosed in 2006 among females aged 10 through 30 years were also matched with the birth records; cancer registry-birth matches were merged with the IIS-birth matches using the birth record identifier.Overall, 68% of the 1274,282 IIS and 61% of the 1358 cancer registry records could be matched with birth records. Among the sample of IIS-birth matches, most (86%) were continuous residents. Seventy percent or more of cancer registry-birth matches merged with IIS-birth matches for cases born after 1984.This is the first effort in the U.S. to show that linking records across IIS and cancer registries is practical and reasonably efficient. The increasing proportion of matches between the registries and live birth file with birth year, and the use of population-based data, strengthen the utility of this approach. Future steps include use of this method to examine incidence of cervical cancer precursors in HPV immunization-eligible females.     

淮安市淮阴区2009年居民恶性肿瘤死亡及减寿年数分析

目的：描述淮阴区居民主要恶性肿瘤死亡的情况及对人群寿命的影响.方法：利用肿瘤登记和死因监测系统收集淮阴区居民2009年恶性肿瘤死亡资料.计算死亡率、标化死亡率、潜在减寿年数、减寿率、平均减寿年数等指标.结果：2009年淮阴区居民恶性肿瘤死亡率为156.24/10万,标化死亡率为132.33/10万,占全死因的30.03%;男女死亡率比为1：0.5.恶性肿瘤死亡前5位依次为食管癌、肺癌、肝癌、胃癌和肠癌,死亡率随年龄增长而逐渐上升.恶性肿瘤死亡造成的潜在减寿年数（PYLL）为17 171人年,减寿率为19.18‰,平均减寿年数（AYLL）为12.27年,潜在减寿年数顺位处于第1的是肝癌.结论：恶性肿瘤已成为严重危害淮阴区居民生命健康的主要疾病,加强肿瘤防治是本区今后社区综合防治工作的重点.     

Linking environmental hazards and birth defects data

The authors describe methods for linking birth certificate and birth defect registry data to potential environmental hazards and assess potential confounding factors. Cases of selected birth defects from the Texas Birth Defects Registry were linked to their respective birth/ fetal death records. Comparison births were randomly selected from the 1996-2000 Texas birth records. Maternal addresses were related through a geographic information system to boundaries of hazardous waste sites and point locations of industries. Approximately 89% of maternal addresses of case births and 88% of comparison births were successfully related in distance to these sites and industries. Maternal characteristics associated with living within one mile of these sites included belonging to any group besides non-Hispanic white and having lower education attainment (< 16 years) or a residence within the city limits. In linking environmental and health outcome databases, researchers should be aware of factors that may confound associations between exposure and outcomes.     

A comparison of analyses of occupational bladder cancer: Death certificate vs. population-based case-control interview data

The authors examined the utility of death certificate data for occupational health surveillance by comparing the ability of the data to identify high-risk occupations for bladder cancer with that of a population-based case-control study. Death certificate data for white males from 23 states for 1979–1987 were analyzed using proportionate mortality ratios. The case-control study used cancer registry cases for 1977–1978. Results were compared for 21 a priori suspect occupations. A broad definition of agreement resulted in agreement for 62% of the occupations; the death certificate study identified eight of 15 occupations identified by the case-control study and neither study identified five of the categories. While death certificate data have many limitations, our results indicate that death certificate data can provide clues to some potential occupational health problems. With the advantages of inexpensive data, large sample size, and industrial coverage, more refined analyses of the data should prove useful for occupational mortality surveillance and hypothesis generation. © 1994 Wiley-Liss, Inc.     

Establishing baseline data in cancer registration in northern England: implications for Health of the Nation targets.

OBJECTIVE--To assess the completeness and accuracy of cancer surveillance data relevant to Health of the Nation targets. DESIGN--A comparison of locally ascertained data on cancer with recorded cancer registry sources in selected diagnoses. SETTING--The district of South West Durham within the Northern Regional Health Authority. PATIENTS--All patients with lung, skin, and malignant cervical cancer who were resident and diagnosed in the district or identified in the Northern Region Cancer Registry during the calendar period 1989-91. MAIN RESULTS--Of 544 cases of cancer identified from all available sources, 448 (95.8%) were registered, ranging from 93.9% for malignant cervical cancer to 96.7% for skin cancer. In 448 cases which were both identified locally and registered, 53 (11.8%) showed disagreements between local sources and register data, involving classification of site and timing of registration. Twenty three cases were identified locally but were not registered, 22 registered but not identified locally, and 51 registered with the casenotes missing locally. CONCLUSIONS--Any real achievement of Health of the Nation targets may be masked by changes over time in the accuracy and completeness of information systems. In assessing the achievement or otherwise of targets, it is important to be aware of any differences in the completeness and accuracy of the baseline data compared to future measurements.     

Evaluation of the hospital discharge diagnoses index and the birth certificate as sources of information on birth defects

The hospital discharge diagnoses index (DI) for newborns and the birth certificate were evaluated as sources of information about birth defects by comparing them with the same births in the case registry of the California Birth Defects Monitoring Program (CBDMP). The CBDMP is an active surveillance system; the staff visit hospitals to identify children with birth defects diagnosed in the first year of life. The study population comprised 66,481 live births to residents of five counties in the San Francisco Bay area in 1983. Of these infants, 2,543 had at least one birth defect noted on the DI, and 1,623 were in the CBDMP registry; 1,020 with defects noted on the DI were also in the CBDMP registry. For this same population, 399 infants had one or more defects noted on the birth certificate; 304 of these were also in the CBDMP registry. Reporting of birth defects on the birth certificate was poor for every condition. Reporting on the DI was most reliable for oral clefts and chromosomal defects; for these defects, the DI omitted one-third of the cases but had identified only about 10 percent false-positive (that is, unverified) cases. Major central nervous system malformations were less well reported, with about one-third of them false-positive. For all other birth defects, the DI either omitted more than half of the cases, or more than half of the cases reported were false-positive cases. These findings raise questions about the validity of analytic studies of birth defects if the data are obtained only from the DI or the birth certificate.     

The geography of survival after surgery for colo-rectal cancer in southern England

This study investigates variations in survival following surgery for colo-rectal cancer in the Wessex region (part of southern England), using 5147 cases diagnosed between 1 September 1991 and 31 August 1995. Survival curve estimation by life tables and Cox's proportional hazards model were used to examine geographical variation in cancer survival, with a specific focus on distance between place of residence and treatment centre, and district of treatment. We also consider whether area deprivation has an impact on survival. In seeking to answer these questions we control for possible confounders, including: age, gender, site of tumour, stage of disease at operation, hospital size and surgery type (whether elective or non-elective). District of treatment, distance and deprivation all show a relationship to outcome using survival curves, but when adjusting for other covariates using the Cox model, and considering deaths from all causes, only district of treatment was a very significant covariate (p < 0.0001). Distance, deprivation, and gender were only weakly significant (p < 0.10). Considering only deaths related to operation (within 30 days) district of treatment remained significant, but while distance had some effect on outcome, deprivation and gender ceased to be significant covariates. There is some evidence that those who live furthest from centres of treatment have the worst outcomes but the 'geography of survival' manifests itself more through where patients are treated than through area (deprivation) effects or relative location. The results have important policy implications, as they show variations among treatment centres having controlled for potentially confounding factors.     

Using cancer registry data for survival studies: the example of the Ontario Cancer Registry

Background and ObjectivesThe Ontario Cancer Registry (OCR) is a population-based tumor registry created to provide data for epidemiologic research and for cancer surveillance. Recently it has been used for health services research. The objective of this project was to assess the quality of the OCR data that is used in survival analysis.Methods and DesignClinical information for 898 patients with squamous carcinoma of the head and neck including index tumor site, date of diagnosis, vital status, date of death, and cause of death from a prospective database at the Kingston Regional Cancer Center is compared to the same data elements in the OCR for the same patients.ResultsThere is no statistically significant difference in disease-specific survival between the information from the two databases (log rank P = .89). The OCR captured and correctly assigned index tumor site for 81.4% (detection rate). The site assignment was accurate 90.9% of the time (confirmation rate), there was agreement on vital status (dead vs. alive) for all but one patient, and there was excellent agreement on date of death. However, cause of death (cancer vs. noncancer) based on death certificates had a 31% error rate.ConclusionResearchers can be confident in the survival analysis generated from data in this registry, but need to be aware of potential sources of error.