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Background:Period analysis is increasingly used to compute long-term cancer survival, as it provides better prediction of survival of newly diagnosed patients than traditional cohort analysis. However, the patient population to which period survival estimates best pertain to and which should be described in a study is less obvious.Methods:Using Finnish Cancer Registry data on 23 common cancer sites, age-standardized period estimates of 5-, 10-, 15-, and 20-year relative survival were computed for each 2-, 5-, and 10-year calendar period in 1954-2003 and compared with survival estimates for two cohorts by means of mean, mean absolute and mean squared differences: a full cohort of all patients potentially contributing some data to the survival analysis and a restricted cohort of patients diagnosed in the period of interest.Results:In most computations, survival estimates for the full cohorts were on average closer to the period estimates for the majority of cancer sites. For 10-year survival, results were less obvious with respect to the mean difference. However, mean squared and mean absolute differences were smaller for the majority of cancers when using the full cohort.Conclusion:Our results suggest that the full cohort should be described in reports of period survival analysis. [ABSTRACT FROM AUTHOR]

Background:Relative survival estimates cancer survival in the absence of other causes of death. Previous work has shown that standard errors of non-standardised relative survival may be substantially overestimated by the conventionally used method. However, evidence was restricted to non-standardised relative survival estimates using Hakulinen's method. Here, we provide a more comprehensive evaluation of the accuracy of standard errors including age-standardised survival and estimation by the Ederer II method.Methods:Five- and ten-year non-standardised and age-standardised relative survival was estimated for patients diagnosed with 25 common forms of cancer in Finland in 1989-1993, using data from the nationwide Finnish Cancer Registry. Standard errors of mutually comparable non-standardised and age-standardised relative survival were computed by the conventionally used method and compared with bootstrap standard errors.Results:When using Hakulinen's method, standard errors of non-standardised relative survival were overestimated by up to 28%. In contrast, standard errors of age-standardised relative survival were accurately estimated. When using the Ederer II method, deviations of the standard errors of non-standardised and age-standardised relative survival were generally small to negligible.Conclusion:In most cases, overestimations of standard errors are effectively overcome by age standardisation and by using Ederer II rather than Hakulinen's method. [ABSTRACT FROM AUTHOR]

Background: Previous studies have reported lower colorectal cancer (CRC) survival in patients with low compared to high educational levels. We investigated the impact of education on CRC survival by using both individual and area-based information on education., Methods: Patients diagnosed with CRC in Finland in 2007-2016 were followed up for death until the end of 2016. Age-standardized relative survival and relative excess risk of death (RER) were estimated by sex using period approach. RERs were adjusted for age, stage at diagnosis, cancer site, urbanity, hospital district and municipality by using Bayesian piecewise constant excess hazard models. Analyses were conducted including individual (basic, secondary, high) and area-based (quartiles Q1-Q4 based on the proportion of population with basic education) education separately as well as both measures in one model., Results: We analysed in all 24 462 CRC patients. There was a clear gradient in 5-year relative survival across education groups (men: basic 62 %, secondary 64 %, high 69 %; women: basic 61 %, secondary 67 %, high 71 %). Compared to the basic education group, RER in the high education group was significantly lower. This association was still present after including area-based education in the models (men: RER 0.72, 95 % Confidence interval (CI) 0.64-0.81; women: RER 0.76, 95 % CI 0.59-0.96). Area-based education revealed smaller effect estimates than individual education in CRC survival and no association for men., Conclusion: Individual education information should be preferred over area-based when survival differences are studied by education. Educational differences in CRC survival are still present in Finland., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Individuals heterozygous for germline ATM mutations have been reported to have an increased risk for breast cancer but the role for ATM genetic variants for breast cancer risk has remained unclear. Recently, a common ATM variant, ATMivs38 -8T>C in cis with the ATMex39 5557G>A (D1853N) variant, was suggested to associate with bilateral breast cancer among familial breast cancer patients from Northern Finland. We have here evaluated the 5557G>A and ivs38-8T>C variants in an extensive case-control association analysis. We also aimed to investigate whether there are other ATM mutations or variants contributing to breast cancer risk in our population., Methods: Two common ATM variants, 5557G>A and ivs38-8T>C, previously suggested to associate with bilateral breast cancer, were genotyped in an extensive set of 786 familial and 884 unselected breast cancer cases as well as 708 healthy controls. We also screened the entire coding region and exon-intron boundaries of the ATM gene in 47 familial breast cancer patients and constructed haplotypes of the patients. The identified variants were also evaluated for increased breast cancer risk among additional breast cancer cases and controls., Results: Neither of the two common variants, 5557G>A and ivs38-8T>C, nor any haplotype containing them, was significantly associated with breast cancer risk, bilateral breast cancer or multiple primary cancers in any of the patient groups or subgoups. Three rare missense alterations and one intronic change were each found in only one patient of over 250 familial patients studied and not among controls. The fourth missense alteration studied further was found with closely similar frequencies in over 600 familial cases and controls., Conclusion: Altogether, our results suggest very minor effect, if any, of ATM genetic variants on familial breast cancer in Southern Finland. Our results do not support association of the 5557G>A or ivs38-8T>C variant with increased breast cancer risk or with bilateral breast cancer.