Survival from five common cancers in Georgia, 2015–2019 (CONCORD)

BackgroundPopulation-based cancer survival is a key metric of the effectiveness of health systems in managing cancer. Data from population-based cancer registries are essential for producing reliable and robust cancer survival estimates. Georgia established a national population-based cancer registry on 1 January 2015. This is the first analysis of population-based cancer survival from Georgia.MethodsData were available from the national cancer registry for 16,359 adults who were diagnosed with a cancer of the stomach, colon, rectum, breast (women) or cervix during 2015–2019. We estimated age-specific and age-standardised net survival at one, two and three years after diagnosis for each cancer, by sex.ResultsThe data were of extremely high quality, with less than 2% of data excluded from each dataset. For the patients included in analyses, at least 80% of the tumours were microscopically verified.Age-standardised three-year survival from stomach cancer was 30.6%, similar in men and women. For colon cancer, three-year survival was 60.1%, with survival 4% higher for men than for women. Three-year survival from rectal cancer was similar for men and women, at 54.7%. For women diagnosed with breast cancer, three-year survival was 84.4%, but three-year survival from cervical cancer was only 67.2%.ConclusionEstablishment of a national cancer registry with obligatory cancer registration has enabled the first examination of population-based cancer survival in Georgia. Maintenance of the registry will facilitate continued surveillance of both cancer incidence and survival in the country.     

World-wide trends in net survival from pancreatic cancer by morphological sub-type: An analysis of 1,258,329 adults diagnosed in 58 countries during 2000–2014 (CONCORD-3)

BackgroundDuctal adenocarcinomas and neuroendocrine tumours are the two main morphological sub-types of pancreatic cancer. Using data from CONCORD-3, we examined whether the distribution of morphological sub-types could help explain international variations in pancreatic cancer survival for all morphologies combined. We also examined world-wide survival trends from pancreatic cancer, by morphological sub-type and country.MethodsWe estimated age-standardised one- and five-year net survival by country, calendar period of diagnosis (2000–2004, 2005–2009, 2010–2014) and morphological sub-type, using data from 295 population-based cancer registries in 58 countries for 1,258,329 adults (aged 15–99 years) diagnosed with pancreatic cancer during 2000–2014 and followed up until 31 December 2014.ResultsCarcinomas were by far the most common morphological sub-type, comprising 90% or more of all pancreatic tumours in all countries. Neuroendocrine tumours were rare, generally 0–10% of all tumours.During 2010–2014, age-standardised one-year net survival ranged from 10% to 30% for carcinomas, while it was much higher for neuroendocrine tumours (40% to 80%).Age-standardised five-year survival was generally poor (less than 10 %) for carcinomas, but it ranged from 20% to 50% for neuroendocrine tumours.ConclusionsSurvival from pancreatic carcinoma remains poor world-wide and trends showed little improvement during 2000–2014. Despite slight declines in the proportion of carcinomas, they continue to comprise the majority of pancreatic tumours. Increases in survival from neuroendocrine tumours were greater than those for carcinomas, indicating that enhancements in diagnostic techniques and treatments have helped improve survival over time.     

Role of age and tumour stage in the temporal pattern of 'cure' from stomach cancer: a population-based study in Osaka, Japan

Objectives: To evaluate progress in stomach cancer care in Japan since 1975. Design: Population-based study of data extracted from the Osaka Cancer Registry. Setting: Population-based cancer registry in the area of Osaka Prefecture. Participants: All 66,032 cases diagnosed with a stomach cancer in Osaka Prefecture, Japan between 1975 and 2000 and registered in the Osaka Cancer Registry. Main outcome measures: ‘Cure’ fraction and median survival time for ‘uncured’ patients were estimated with multivariable mixture ‘cure’ model. The role played by age and stage at diagnosis on the changes in ‘cure’ parameters between 1975 and 2000 was evaluated. Missing stage was handled by multiple imputation approach. Results: More than 50% of the patients diagnosed with a stomach cancer in 1996–2000 were estimated ‘cured’ from their cancer, corresponding to a 20% increase since 1975–1980. Median survival time for ‘uncured’ patients however remained unchanged at about 8 months. ‘Cure’ fraction was over 85% for localised tumours and 30% for regional tumours, but stayed as low as 2.5% for distant metastatic cancers. Improvement was underestimated by about 10% because of ageing of cancer patients. Changes in stage distribution explained up to 40% of the increase in ‘cure’ fraction among men and up to 13% in women. Overdiagnosis was unlikely to play any role in these patterns. Conclusions: ‘Cure’ fraction from stomach cancer dramatically increased in Osaka, Japan since 1975, partly because of earlier stage at diagnosis, but mostly due to improvement in treatment of stomach cancer patients. This study, based on a leading country in term of stomach cancer management, provides insightful results for other countries in which ‘cure’ fraction is usually much lower.     

Trend breaks in incidence of non-cardia gastric cancer in the Netherlands

IntroductionThe incidence of gastric cancer declined over the past decades. Recently, unfavorable trend breaks (i.e. rise in incidence) were seen for non-cardia cancer in younger age groups in the US. It is unclear whether these also occur in other Western countries. We aimed to analyze the gastric cancer incidence trends by age, sex, subsite and stage in the Netherlands.MethodsData on all patients with gastric adenocarcinoma diagnosed from 1973 to 2011 (n = 9093) were obtained from the population-based Eindhoven cancer registry. Incidence time trends (European standardized rates per 100,000) were separately analyzed by sex, age group (<60, 60–74, and >75 years), subsite, and pathological stage. Joinpoint analyses were performed to discern trend breaks, age–period–cohort analyses to examine the influence of longitudinal and cross-sectional changes.ResultsThe incidence of non-cardia cancer declined annually by 3.5% (95% CI −3.8; −3.3). However, in males <60 years, the incidence flattened since 2006, and tended to rise in those >74 years. This pertained to corpus cancers. The incidence of cardia cancer peaked in 1985 and decreased subsequently by 2.4% (95% CI −3.2; −1.5) yearly. The absolute incidence of stage IV disease at first diagnosis initially decreased, but then remained stable over the past 15–20 years.ConclusionsThe incidence of non-cardia cancer declined over the past four decades in the Netherlands, but now seems to be stabilizing particularly in males. Unfavorable trend breaks are seen for corpus cancer in younger and older males. The trend breaks in the Netherlands are however not similar to those observed in the US.     

Socioeconomic inequalities in breast cancer survival in Reunion Island: The contribution of stage at diagnosis as a mediator

IntroductionAlthough breast cancer survival has improved in France, it appears that women living in deprived areas are more likely to die from breast cancer. However, no study has yet examined socioeconomic inequalities in breast cancer survival in La Réunion. Our objective was to examine whether socioeconomic inequalities in breast cancer survival exist in Reunion Island and whether stage at diagnosis could partly explain these differences.MethodsA population-based cohort study of all women on Reunion Island with primary breast cancer diagnosed between 2008 and 2016 was conducted. Each woman was assigned a deprivation index based on her area of residence at diagnosis. Net survival by deprivation group and stage at diagnosis was estimated by the non parametric Pohar Perme method. The role of stage (indirect effect) was assessed using a mediation analysis extended to the relative survival framework.ResultsAt five years, net survival was significantly lower in women living in the most deprived areas than in women living in the least deprived areas (81 % (95 % CI 77–86) and 91 % (95 % CI 89–94), respectively, p < 0.0001), and mediation analysis showed that the contribution of stage at diagnosis to these survival differences was 43 %.DiscussionOur result shows that although measures to promote earlier diagnosis are important, they would only reduce socioeconomic inequalities in breast cancer survival by 43 %. To further investigate these inequalities, future research should explore the role of unmeasured mediators, such as comorbidities and treatment received, as well as the impact of specific interventions that might address the differences in mediator distribution.     

Cancer survival in the northwestern of São Paulo State,Brazil: A population-based study

BackgroundPopulation-based cancer registry (PBCR) data provide crucial information for evaluating the effectiveness of cancer services and reflect prospects for cure by estimating population-based cancer survival. This study provides long-term trends in survival among patients diagnosed with cancer in the Barretos region (São Paulo State, Brazil).MethodsIn this population-based study, we estimated the one- and five-year age-standardized net survival rates of 13,246 patients diagnosed with 24 different cancer types in Barretos region between 2000 and 2018. The results were presented by sex, time since diagnosis, disease stage, and period of diagnosis.ResultsMarked differences in the one- and five-year age-standardized net survival rates were observed across the cancer sites. Pancreatic cancer had the lowest 5-year net survival (5.5 %, 95 %CI: 2.9–9.4) followed by oesophageal cancer (5.6 %, 95 %CI: 3.0–9.4), while prostate cancer ranked the best (92.1 %, 95 %CI: 87.8–94.9), followed by thyroid cancer (87.4 %, 95 %CI: 69.9–95.1) and female breast cancer (78.3 %, 95 %CI: 74.5–81.6). The survival rates differed substantially according to sex and clinical stage. Comparing the first (2000–2005) and last (2012–2018) periods, cancer survival improved, especially for thyroid, leukemia, and pharyngeal cancers, with differences of 34.4 %, 29.0 %, and 28.7 %, respectively.ConclusionTo our knowledge, this is the first study to evaluate long-term cancer survival in the Barretos region, showing an overall improvement over the last two decades. Survival varied by site, indicating the need for multiple cancer control actions in the future with a lower burden of cancer.     

Survival of cancer patients in urban and rural areas of Germany—A comparison

BackgroundCancer care services including cancer prevention activities are predominantly localised in central cities, potentially causing a heterogeneous geographic access to cancer care. The question of an association between residence in either urban or rural areas and cancer survival has been analysed in other parts of the world with inconsistent results. This study aims at a comparison of age-standardised 5-year survival of cancer patients resident in German urban and rural regions using data from 11 population-based cancer registries covering a population of 33 million people.Material and methodsPatients diagnosed with cancers of the most frequent and of some rare sites in 1997–2006 were included in the analyses. Places of residence were assigned to rural and urban areas according to administrative district types of settlement structure. Period analysis and district type specific population life tables were used to calculate overall age-standardised 5-year relative survival estimates for the period 2002–2006. Poisson regression models for excess mortality (relative survival) were used to test for statistical significance.ResultsThe 5-year relative survival estimates varied little among district types for most of the common sites with no consistent trend. Significant differences were found for female breast cancer patients and male malignant melanoma patients resident in city core regions with slightly better survival compared to all other district types, particularly for patients aged 65 years and older.ConclusionWith regard to residence in urban or rural areas, the results of our study indicate that there are no severe differences concerning quality and accessibility of oncological care in Germany among different district types of settlement.     

Difference in net survival using regional and national life tables in Japan

BackgroundNational life table is commonly used for estimating cancer net survival. However, the national life table does not reflect condition of people in local area accurately, because there are disparities in cancer mortality rates among the local area in many cases. We investigated magnitude of difference in cancer net survival using the local area in Japan and Japanese life tables.MethodsWe analyzed data from 32,942 cancer patients diagnosed between 2010 and 2012 in Aomori prefecture, Japan. Expected survival rates in Aomori (ESA) and Japan (ESJ) were estimated based on the life table of each area. Five-year net survival rates using ESA and the ESJ were estimated using the Pohar-Perme method.ResultsThe difference between net survival rates using the ESA (NSA) and the ESJ (NSJ) were larger than in men (0.3－3.0%) than in women (0.1－0.8%). The largest difference in the net survival rate was observed in prostate cancer patients, because the difference in the expected survival in oldest old men was remarkable.ConclusionTwo factors affected the difference in the net survival rates resulting from the sensitivity analysis. The difference was larger (1) among older patients or (2) with a longer observation period (person-years).     

Ethnic,racial and socioeconomic disparities in breast cancer survival in two Brazilian capitals between 1996 and 2012

ObjectiveTo study the impact of socio-economic status and ethno-racial strata on excess mortality hazard and net survival of women with breast cancer in two Brazilian state capitals.MethodWe conducted a survival analysis with individual data from population-based cancer registries including women with breast cancer diagnosed between 1996 and 2012 in Aracaju and Curitiba. The main outcomes were the excess mortality hazard (EMH) and net survival. The associations of age, year of diagnosis, disease stage, race/skin colour and socioeconomic status (SES) with the excess mortality hazard and net survival were analysed using multi-level spline regression models, modelled as cubic splines with knots at 1 and 5 years of follow-up.ResultsA total of 2045 women in Aracaju and 7872 in Curitiba were included in the analyses. The EMH was higher for women with lower SES and for black and brown women in both municipalities. The greatest difference in excess mortality was seen between the most deprived women and the most affluent women in Curitiba, hazard ratio (HR) 1.93 (95%CI 1.63–2.28). For race/skin colour, the greatest ratio was found in Curitiba (HR 1.35, 95%CI 1.09–1.66) for black women compared with white women. The most important socio-economic difference in net survival was seen in Aracaju. Age-standardised net survival at five years was 55.7% for the most deprived women and 67.2% for the most affluent. Net survival at eight years was 48.3% and 61.0%, respectively. Net survival in Curitiba was higher than in Aracaju in all SES groups.”ConclusionOur findings suggest the presence of contrasting breast cancer survival expectancy in Aracaju and Curitiba, highlighting regional inequalities in access to health care. Lower survival among brown and black women, and those in lower SES groups indicates that early detection, early diagnosis and timely access to treatment must be prioritized to reduce inequalities in outcome among Brazilian women.     

Net survival in recurrence-free colon cancer patients

PurposeConditional net survival in recurrence-free patients (CNS-RF) provides relevant clinical information and has never been assessed yet in a non-selected colon cancer population. We aimed to estimate conditional 5-year net survival in recurrence-free patients with colon cancer in the population-based Digestive Cancer Registry of Burgundy (France).MethodsCNS-RF was estimated in the 3736 patients resected for cure for primary colon cancer between 1976 and 2006, using a flexible parametric model of net survival for every additional year survived at diagnosis and from 1 to 5 years thereafter.ResultsThe net probability of surviving 5 more years increased from 72% at diagnosis to 92% for recurrence-free patients who survived 5 years after diagnosis. CNS-RF was over 90% 3 years after diagnosis in patients aged 75 and below. CNS-RF was over 95% in patients diagnosed after 2000 who were recurrence-free 3, 4 or 5 years after diagnosis. CNS-RF was similar between patients with stage I and II disease from 2 years after diagnosis and patients with stage III disease from 5 years after diagnosis. The initial differences in net survival related to gross features, clinical presentation, number of harvested nodes in stage II, and number of involved nodes in stage III disappeared after 2 years.ConclusionsCNS-RF is a relevant measure of prognosis in patients who have already achieved a period of remission. Providing an updated estimation of prognosis in the years following diagnosis may improve the survivors’ quality of life and access to credit or insurance.     

Stage at diagnosis for childhood solid cancers in Australia: A population-based study

BackgroundStage of cancer at diagnosis is one of the strongest predictors of survival and is essential for population cancer surveillance, comparison of cancer outcomes and to guide national cancer control strategies. Our aim was to describe, for the first time, the distribution of cases by stage at diagnosis and differences in stage-specific survival on a population basis for a range of childhood solid cancers in Australia.MethodsThe study cohort was drawn from the population-based Australian Childhood Cancer Registry and comprised children (<15 years) diagnosed with one of 12 solid malignancies between 2006 and 2014. Stage at diagnosis was assigned according to the Toronto Paediatric Cancer Stage Guidelines. Observed (all cause) survival was calculated using the Kaplan-Meier method, with follow-up on mortality available to 31 December 2015.ResultsAlmost three-quarters (1256 of 1760 cases, 71%) of children in the study had localised or regional disease at diagnosis, varying from 43% for neuroblastoma to 99% for retinoblastoma. Differences in 5-year observed survival by stage were greatest for osteosarcoma (localised 85% (95% CI = 72%–93%) versus metastatic 37% (15%–59%)), neuroblastoma (localised 98% (91%–99%) versus metastatic 60% (52%–67%)), rhabdomyosarcoma (localised 85% (71%–93%) versus metastatic 53% (34%–69%)), and medulloblastoma (localised 69% (61%–75%) versus metastases to spine 42% (27%–57%)).ConclusionThe stage-specific information presented here provides a basis for comparison with other international population cancer registries. Understanding variations in survival by stage at diagnosis will help with the targeted formation of initiatives to improve outcomes for children with cancer.     

Subsite- and stage-specific colorectal cancer trends in Estonia prior to implementation of screening

BackgroundThe occurrence of colorectal cancer (CRC) in Estonia has been characterised by increasing incidence, low survival and no screening. The study aimed to examine long-term incidence and survival trends of CRC in Estonia with specific focus on subsite and stage.MethodsWe analysed CRC incidence and relative survival using Estonian Cancer Registry data on all cases of colorectal cancer (ICD-10 C18–21) diagnosed in 1995–2014. TNM classification was used to categorise stage.ResultsAge-standardized incidence of colon cancer increased both in men and women at a rate of approximately 1% per year. Significant increase was seen for right-sided tumours, but not for left-sided tumours. Rectal cancer incidence increased significantly only in men and anal cancer incidence only in women. Age-standardized five-year relative survival for colon cancer increased from 50% in 1995–1999 to 59% in 2010–2014; for rectal cancer, from 38% to 56%. Colon cancer survival improved significantly for left-sided tumours (from 51% to 62%) and stage IV disease (from 6% to 15%). For rectal cancer, significant survival gain was seen for stage II (from 58% to 75%), stage III (from 34% to 70%) and stage IV (from 1% to 12%).ConclusionIn the pre-screening era in Estonia, increase in colon cancer incidence was limited to right-sided tumours. Large stage-specific survival gain, particularly for rectal cancer, was probably due to better staging and advances in multimodality treatment. Nonetheless, more than one quarter of new CRC cases are diagnosed at stage IV, emphasising the need for an efficient screening program.     

Relative survival analysis of gynecological cancers in an urban district of Shanghai during 2002–2013

ObjectiveAppraisal of cancer survival is essential for cancer control, but studies related to gynecological cancer are scarce. Using cancer registration data, we conducted an in-depth survival analysis of cervical, uterine corpus, and ovarian cancers in an urban district of Shanghai during 2002–2013.Materials and methodsThe follow-up data of gynecological cancer from the Changning District of Shanghai, China, were used to estimate the 1–5-year observed survival rate (OSR) and relative survival rate (RSR) by time periods and age groups during 2002–2013. Age-standardized relative survival rates estimated by the international cancer survival standards were calculated during 2002–2013 to describe the prognosis of cervical, uterine corpus, and ovarian cancers among women in the district.ResultsIn total, 1307 gynecological cancer cases were included in the survival analysis in the district during 2002–2013. Among gynecological cancers, the 5-year OSRs and RSRs of uterine corpus cancer were highest (5-year OSR 84.40%, 5-year RSR 87.67%), followed by those of cervical cancer (5-year OSR 73.58%, 5-year RSR 75.91%), and those of ovarian cancer (5-year OSR 53.89%, 5-year RSR 55.90%). After age adjustment, the 5-year relative survival rates of three gynecological cancers were 71.23%, 80.11%, and 43.27%, respectively.ConclusionThe 5-year relative survival rate did not show a systematic temporal trend in cervical cancer, uterine cancer, or ovarian cancer. The prognosis in elderly patients was not optimistic, and this needs a more advanced strategy for early diagnosis and treatment. The age structure of gynecological cancer patients in the district tended to be younger than the standardized age, which implies that more attention to the guidance and health education for the younger generation is needed.     

Validity of initial cancer diagnoses in the Diagnosis Procedure Combination data in Japan

BackgroundIn Japan, the Diagnosis Procedure Combination (DPC) data have been used as a nationwide administrative hospital discharge database for clinical studies. However, few studies have evaluated the validity of recorded diagnoses of cancer in the database.MethodsWe compared the DPC data with hospital-based cancer registries in Osaka Prefecture, Japan to assess the validity of the recorded cancer diagnoses in the DPC data. Fifteen types of cancer were included in the analysis. Cancer stage with tumor-node-metastasis (TNM) classification was assessed for eight cancer types with >400 patients. We evaluated concordance and positive predictive value of cancer diagnosis, and concordance of cancer stage between the DPC data and the hospital-based cancer registry.ResultsIn total, we identified 29,180 eligible patients. The five types of cancer with the highest number of patients were as follows: 6,765 (23.2 %) colorectal, 6,476 (22.2 %) stomach, 4,862 (16.7 %) breast, 4,445 (15.2 %) lung, and 2,257 (7.7 %) liver. Concordance of diagnosis ranged from 63.9 %–99.5 %, and twelve of the fifteen types of cancers had concordance of over 90 %. Positive predictive values of diagnosis ranged from 86.8 %–100 %. Regarding cancer stage, the overall degree of concordance was 67.2 % in all patients and the concordance was over 70 % in four types of cancers.ConclusionsThe DPC data had high validity of cancer diagnosis. However, the potential impact of the misclassifications and low concordance in cancer stage among specific type of cancers in the DPC data should be considered.     

Diverging trends in recent population-based survival rates in oesophageal and gastric cancer

Background

Survival trends in oesophageal and gastric cancer need to be updated. A nationwide Swedish population-based study in 1961–2009 was based on registry data.

Methodology/Principal Findings

Relative survival rate, i.e. the ratio of the observed to the expected survival, adjusted for age, sex, and calendar period, and presented with 95% confidence intervals (CI), was the main outcome measure. The expected survival was calculated using the corresponding Swedish general population with no exclusions. The relative survival rates in oesophageal and gastric cardia adenocarcinoma have improved since the 1990s (p for trend <0.001), but not in oesophageal squamous cell carcinoma or gastric non-cardia adenocarcinoma. The relative 5-year survival rates during the two recent periods 1990–1999 and 2000–2008 were 12.5% (95%CI 10.1%–14.9%) and 10.3% (95%CI 8.5–12.0%) for oesophageal squamous cell carcinoma, 12.5% (95%CI 10.1%–14.9%) and 14.6% (95%CI 12.6–16.6%) for oesophageal adenocarcinoma, 11.1% (95%CI 9.6%–12.6%) and 14.3% (95%CI 12.3–16.3%) for gastric cardia adenocarcinoma, and 20.2% (95%CI 19.2%–21.1%) and 19.0% (95%CI 17.7–20.2%) for gastric non-cardia adenocarcinoma. The 3-year survival in tumour stage III in 2004–2008 was about 25% for all four tumour types.

Conclusions/Significance

The survival in oesophageal and cardia adenocarcinoma is increasing, but the lack of such increase in oesophageal squamous cell carcinoma and gastric non-cardia adenocarcinoma is a concern.     

Epstein Barr virus antibody reactivity and gastric cancer: A population-based case-control study

BackgroundIn contrast to the recognized role of Helicobacter pylori in the etiology of non-cardia gastric cancer (GC), there is still insufficient epidemiological evidence for the involvement of Epstein-Barr virus (EBV) in gastric carcinogenesis. We aimed to evaluate the relation of antibody profile and antibody reactivity intensity against four individual EBV proteins to GC risk.MethodsWe used information from 281 GC cases and 2071 age and sex frequency matched controls recruited in the frame of the MCC-Spain multicase-control study, between 2008 and 2013. Sociodemographic, lifestyle and environmental factors were assessed in face-to-face interviews. Antibody responses to four EBV proteins (EBNA-1, ZEBRA, EA-D, and VCA-p18) were analyzed by multiplex serology. Odds ratios (OR) and 95% confidence intervals were calculated by using logistic regression mixed models to evaluate the association of seropositivity and antibody reactivity against EBV proteins with GC, adjusting for GC risk factors. Stratified analyses by tumor location (cardia vs. non-cardia) and morphology (intestinal vs. diffuse) were done.ResultsAmong controls, seropositivity for EA-D, ZEBRA, EBNA-1 and VCA-p18 was 85%, 91%, 97% and 99%, respectively. Even though seropositivity for none of the studied proteins was associated with a higher GC risk, increasing antibody reactivity against EBNA-1 and VCA-p18 was associated with higher OR of GC. This association was present for cardia and non-cardia cancer cases, and for intestinal and diffuse types.ConclusionOur results support the hypothesis that EBV may play a role in GC etiology, and highlight the importance of evaluating specific antibodies and the dose-response relations when studying widespread infections.     

Population-based cancer survival in the Golestan province in the northeastern part of Iran 2007–2012

ObjectiveWe studied 5-year relative survival (RS) for 14 leading cancer sites in the population-based cancer registry (PBCR) of Golestan province in the northeastern part of Iran.MethodologyWe followed patients diagnosed in 2007–2012 through data linkage with different databases, including the national causes of death registry and vital statistics office. We also followed the remaining patients through active contact. We used relative survival (RS) analysis to estimate 5-year age-standardized net survival for each cancer site. Multiple Imputation (MI) method was performed to obtain vital status for loss to follow-up (LTFU) cases.ResultsWe followed 6910 cancer patients from Golestan PBCR. However, 2162 patients were loss to follow-up. We found a higher RS in women (29.5%, 95% CI, 27.5, 31.7) than men (21.0%, 95% CI, 19.5, 22.5). The highest RS was observed for breast cancer in women (RS=49.8%, 95% CI, 42.2, 56.9) and colon cancer in men (RS=37.9%, 95% CI, 31.2, 44.6). Pancreatic cancer had the lowest RS both in men (RS= 8.7%, 95% CI, 4.1, 13.5) and women (RS= 7.9%, 95% CI, 5.0, 10.8)ConclusionAlthough the 5-year cancer survival rates were relatively low in the Golestan province, there were distinct variations by cancer site. Further studies are required to evaluate the survival trends in Golestan province over time and compare them with the rates in the neighboring provinces and other countries in the region.     

Robustness of individual and marginal model-based estimates: A sensitivity analysis of flexible parametric models

BackgroundFlexible parametric survival models (FPMs) are commonly used in epidemiology. These are preferred as a wide range of hazard shapes can be captured using splines to model the log-cumulative hazard function and can include time-dependent effects for more flexibility. An important issue is the number of knots used for splines. The reliability of estimates are assessed using English data for 10 cancer types and the use of online interactive graphs to enable a more comprehensive sensitivity analysis at the control of the user is demonstrated.MethodsSixty FPMs were fitted to each cancer type with varying degrees of freedom to model the baseline excess hazard and the main and time-dependent effect of age. For each model, we obtained age-specific, age-group and internally age-standardised relative survival estimates. The Akaike Information Criterion and Bayesian Information Criterion were also calculated and comparative estimates were obtained using the Ederer II and Pohar Perme methods. Web-based interactive graphs were developed to present results.ResultsAge-standardised estimates were very insensitive to the exact number of knots for the splines. Age-group survival is also stable with negligible differences between models. Age-specific estimates are less stable especially for the youngest and oldest patients, of whom there are very few, but for most scenarios perform well.ConclusionAlthough estimates do not depend heavily on the number of knots, too few knots should be avoided, as they can result in a poor fit. Interactive graphs engage researchers in assessing model sensitivity to a wide range of scenarios and their use is highly encouraged.     

Increasing incidence and survival of corpus uteri cancer in Estonia over the past two decades

BackgroundCorpus uteri cancer has become the fourth most common female cancer in Europe. In Estonia, the prevalence of obesity is increasing, and corpus uteri cancer survival has been relatively low. The aim of the study was to evaluate incidence, mortality and survival trends of corpus uteri cancer in Estonia by age, stage and histological subtypes with an emphasis on surgical treatment.MethodsEstonian Cancer Registry data on incident cases of corpus uteri cancer were used to examine incidence trends (1995–2016) and calculate relative survival ratios (RSR) (1996–2016). Cases were classified by morphology and FIGO stage. Causes of Death Registry data were used to analyse corrected mortality (1995–2017).ResultsA total of 4281 cases were diagnosed in 1996–2016. A significant increase was seen in age-standardized incidence from 2009, while mortality remained stable throughout the study period. Significant increases were observed for type I cancers and age groups ≥65 years. Overall age-standardized 5-year RSR improved from 70% in 1996–2002 to 78% in 2010–2016. Survival increased for type I cancers, all age groups and all stages (significantly for stage IV). The proportion of surgically treated cases increased significantly from 85% to 89%, with the largest increases seen in older age groups and later stages.DiscussionThe rising corpus uteri cancer incidence in Estonia is driven by the type I cancer trend. Survival gain for later stages and older age groups likely reflected more frequent surgical treatment. To reduce mortality, further efforts are necessary to ensure appropriate care for all patients.     

Do prognoses of patients with second primary cancers differ from those of patients with no prior cancer? A population-based study

BackgroundSome cancer survivors develop second primary cancers. However, differences in prognosis between patients who have and have not had prior cancer have not been established. We examined and compared the prognoses of such patients.MethodsUsing the record-linked database of the population-based Cancer Registry of Osaka Prefecture and Vital Statistics in Japan, we identified patients aged ≥ 40 years who were diagnosed with stomach (n = 70,946), colorectal (n = 60,582), or lung (n = 58,016) cancers during 1995–2009. We defined these cancers as index cancers. Patients were classified into three groups according to history of prior cancer and interval between diagnosis of index and prior cancer: single (no prior cancer or interval of ≥10 years), synchronous (interval ≤3 months), and metachronous (interval 3 months to 10 years). The 5-year prognosis from index cancer diagnosis was investigated using the Kaplan–Meier method and log-rank test.Results5-year prognoses of patients with synchronous stomach and colorectal cancers were significantly worse than that of patients with single primary, about 60 % of these patients’ deaths being attributable to the prior cancer. In contrast, 5-year prognoses of patients with metachronous primaries were not significantly worse, except for men with colorectal cancer. The percentages of index cancer deaths were 1.7–4.3 times those for non-index cancer deaths.ConclusionA prior cancer contributed to an inferior prognosis in patients with synchronous stomach and colorectal cancers. The prognoses of patients with metachronous primaries were more affected by the index than by the prior cancer, whereas most of them had similar or better prognoses than did patients with a single primary. This finding would help to relieve cancer survivors’ anxiety about their development and prognosis of metachronous second primary cancer.