The completeness of the Swedish Cancer Register – a sample survey for year 1998

Barlow, Lotti; Westergren, Kerstin; Holmberg, Lars; Talbäck, Mats

doi:10.1080/02841860802247664

Cited by 978 publications

(839 citation statements)

References 9 publications

Supporting

Mentioning

831

Contrasting

Order By: Relevance

“…13 The Swedish national cancer register has been validated and shown to have high level of completeness (98%). 45 Leu et al 33 showed that familial risk estimates from linkage of the Swedish multigeneration register and the national cancer register have minimal bias due to lefttruncation of cancer diagnoses before the start-up of cancer registration, thus allowing us to include all cases from 1958 and providing good statistical power. Our work shows how cancer risk changes with time from the first cancer diagnosis in a sibling.…”

Section: Epidemiologymentioning

confidence: 99%

Patterns of changing cancer risks with time since diagnosis of a sibling

Lee

Czene

Rebora

et al. 2014

Intl Journal of Cancer

View full text Add to dashboard Cite

Family history is a well-known risk factor for many cancers. However, it is important to know if/how the familial risk of cancer changes over time. For each of four major cancers (colorectal, breast, prostate and melanoma), we identified siblings of cancer patients (case siblings) and siblings of matched cancer-free controls sampled from Swedish population-based registers. Effects of age and time since diagnosis on sibling risks were examined using Poisson regression and presented graphically as smoothed hazard ratios (HRs). Screening effects were investigated by comparing hazards before/after the introduction of mammography for breast cancer and prostate-specific antigen (PSA) testing for prostate cancer. Case siblings had higher cancer incidence than control siblings for all cancers at all ages, with overall incidence rate ratios (IRRs) of 2.41 (95% confidence interval 2.14-2.71) for colorectal cancer, 2.37 (2.24-2.52) for breast cancer, 3.69 (3.46-3.93) for prostate cancer and 3.20 (2.72-3.76) for melanoma. Risks were highest in siblings who were young when the first cancer was diagnosed in the family, with siblings aged 30-40 having IRR 9.05 (3.03-27.00) for colorectal cancer and 4.30 (2.87-6.45) for breast cancer. Smoothed HRs remained fairly constant for up to 20 years except for prostate cancer, where the HR decreased steeply during the first few years. After introduction of PSA testing, men had higher incidence of prostate cancer shortly after diagnosis in a brother, but no such screening effect was found for breast cancer. Our findings can help inform the screening and counseling of family members of cancer patients.Family history is long recognized as an important risk factor for cancer and has also been found to be associated with cancer prognosis. One of the main, but simple, ways to begin to understand cancer etiology is by identifying the involvement of heritable genes through investigation of familial aggregation. There is a large body of published research providing estimates of increased risk for various cancer sites in different types of relatives. [1][2][3][4] However, in addition to the estimates of overall or lifetime increased risk in family members, it is important to know if/how this risk changes over time. To address this question, different time scales need to be considered when studying the relatives at risk: current age, age at the time of diagnosis of the first cancer in the family, elapsed time from the cancer diagnosis and calendar time.Age is the strongest risk factor for cancer onset and many studies show both the age of relatives and the age of the cancer patient at diagnosis to be associated with the family cancer risk. 5,6 Young age at onset of cancer has been shown to have high heritability and so is an important factor in familial risk. 7,8 However, few studies have investigated in detail how this risk changes with time since the first (index) cancer diagnosis in a family. 9 Such risk profiles would not only provide insight into underlying etiology but could also be used to ...

show abstract

Section: Epidemiologymentioning

confidence: 99%

Patterns of changing cancer risks with time since diagnosis of a sibling

Lee

Czene

Rebora

et al. 2014

Intl Journal of Cancer

View full text Add to dashboard Cite

show abstract

“…The two cohorts were assembled from population-based registers: the first cohort comprising all women with CBC in Sweden from 1976 to 2004, as ascertained from the nationwide and virtually complete Swedish Cancer Register [16,17]. We retrieved information on dates of birth and cancer diagnosis for all patients.…”

Section: Study Populationmentioning

confidence: 99%

Diagnostic work-up of contralateral breast cancers has not improved over calendar period

Sandberg

Hartman

Edgren

et al. 2010

Breast Cancer Res Treat

View full text Add to dashboard Cite

Women who have been treated for breast cancer are typically followed up with regular mammography and palpation, with the aim of detecting recurrences and contralateral breast cancer (CBC). This study aims to investigate if the diagnostic work-up of breast cancer patients has improved over the last 25 years and resulted in earlier diagnoses of CBC. Two population-based cohorts were used; all CBCs in Sweden 1976Sweden -2004Sweden (n: 2932, and all CBCs in Stockholm, Sweden, 1976Sweden, -2005, both cohorts with a maximum of 3 years between the two cancers. Synchronous CBC was defined as two cancers \3 months apart, the remainder was defined as metachronous CBC. We calculated the odds ratio of being diagnosed synchronously, relative to metachronously, using logistic regression, adjusting for whether the second cancer was detected through clinical work-up or not. The odds of synchronous CBC were significantly increased: 1.27 (95% CI, 1.13-1.42) per 5-year period, compared to metachronous, and was not affected by detection mode, but seemed to be explained by adjuvant therapy. The proportion of CBCs detected by clinical work-up did not increase over the study period, and the mean size of the second tumor remained constant. We found an increase in the proportion of synchronous CBCs compared to metachronous, over calendar period, a change that was not associated with clinical work-up, but with adjuvant therapy. This study gives no indications that any improvement in diagnostic work-up of CBC have occurred over the last 25 years.

show abstract

“…All physicians and pathologists are obliged to report all cancer cases, and the register has a minimum 96% nationwide completeness rate. 17 The Register of the Total Population was used to censor cohort members who died or emigrated during follow-up. These patients were censored from the date of first emigration or the exact date of death.…”

Section: Data Collectionmentioning

confidence: 99%