Net survival of women diagnosed with breast tumours: a population-based study in Switzerland.

AIMS OF THE STUDY: Although the incidence of breast carcinoma in situ has been increasing, the prognosis of breast carcinoma in situ patients has not been extensively investigated. Thus, we aimed to compare the characteristics of invasive breast tumours based on whether or not they were preceded by a breast carcinoma in situ and to estimate the 5-year net survival of patients diagnosed with different breast tumours. METHODS: Data from women diagnosed with breast tumours between 2003 and 2016 were used in our analyses. Net survival analyses were performed using inverse probability of censoring weights (nonparametric Pohar Perme estimator). Under certain assumptions, differences in survival between the cancer population and the general population can be considered to be attributable to the cancer diagnosis (NS). RESULTS: Descriptive observation of tumour characteristics indicated that invasive breast tumours following a breast carcinoma in situ were more frequently detected at an earlier stage and had less missing information in tumour-specific variables, compared to invasive breast tumours not preceded by a breast carcinoma in situ. Breast carcinoma in situ patients had a 5-year net survival of 1.02 (95% CI: 1.01-1.03), whereas patients diagnosed with invasive breast cancer without a recorded breast carcinoma in situ had a 5-year net survival of 0.89 (95% CI: 0.88-0.90). Patients diagnosed first with breast carcinoma in situ and then with invasive breast cancer had a 5-year net survival of 0.92 (95% CI: 0.85-1.01). CONCLUSION: Invasive breast tumours that were preceded by a breast carcinoma in situ were detected more frequently at an earlier stage, compared to those that were not. The estimated 5-year net survival of patients with breast tumours was good.

Time-trends and age and stage differences in 5-year relative survival for common cancer types by sex in the canton of Zurich, Switzerland.

BACKGROUND: Survival trends help to evaluate the progress made to reduce the burden of cancer. The aim was to estimate the trends in 5-year relative survival of patients diagnosed with breast, prostate, lung, colorectal cancer and skin melanoma in the time periods 1980-1989, 1990-1999, 2000-2009 and 2010-2015 in the Canton of Zurich, Switzerland. Furthermore, we investigated relative survival differences by TNM stage and age group. METHODS: Data from the Cancer Registry of Zurich was used from 1980 to and including 2015, including incident cases of breast (N = 26,060), prostate (N= 23,858), colorectal (N= 19,305), lung cancer (N= 16,858) and skin melanoma (N= 9780) with follow-up until 31 December 2020. The cohort approach was used to estimate 5-year relative survival. RESULTS: The 5-year relative survival increased significantly between 1980 and 1989, and 2010 and2015: from 0.70 to 0.89 for breast, from 0.60 to 0.92 for prostate, from 0.09 to 0.23 (men) and from 0.10 to 0.27 (women) for lung, from 0.46 to 0.66 (men) and from 0.48 to 0.68 (women) for colorectal cancer, and from 0.74 to 0.94 (men) and from 0.86 to 0.96 (women) for skin melanoma. Survival for stage IV tumors was considerably lower compared to lower-staged tumors for all cancer types. Furthermore, relative survival was similar for the age groups <80 years but lower for patients aged 80 years and older. CONCLUSION: The observed increasing trends in survival are encouraging and likely reflect raised awareness around cancer, improved diagnostic methods, and improved treatments. The fact that stage I tumor patients have generally high relative survival reflects the efforts made regarding early detection.

Is Season of Diagnosis a Predictor of Cancer Survival? Results from the Zurich Cancer Registry.

In Switzerland, there is a large seasonal variation in sunlight, and vitamin D deficiency is relatively common during winter. The season of diagnosis may be linked to cancer survival via vitamin D status. Using data from the Cancer Registry of Zurich, Zug, Schaffhausen, and Schwyz with more than 171,000 cancer cases registered since 1980, we examined the association of the season of diagnosis with survival for cancers including prostate (ICD10 code C61; International Categorization of Diseases, version 10), breast (C50), colorectal (C18-21), lung (C34), melanoma (C43), and all sites combined. Cox proportional hazards regression models were used to assess the differences in the all-cause mortality by the season of the diagnosis. Winter was used as the reference season. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated for all the cancers combined (excluding nonmelanoma skin cancer) and for prostate (in men), breast (in women), colorectal, lung cancer, and melanomas, separately. A diagnosis in summer and/or autumn was associated with improved survival in all the sites combined for both sexes (men: HR 0.97 [95% CI 0.96-0.99]; women: HR 0.97 [95% CI 0.94-0.99]) and in colorectal (HR 0.91 [95% CI 0.84-0.99]), melanoma (HR 0.81 [95% CI 0.65-1.00]), and breast cancer (HR 0.91 [95% CI 0.94-0.99]) in women. Our study results suggest that a cancer diagnosis in summer and/or autumn is associated with a better prognosis. The improved seasonal survival coincides with the seasonal variation of sun-induced vitamin D, and vitamin D may play a protective and beneficial role in cancer survival.

Impact of comorbidities at diagnosis on the 10-year colorectal cancer net survival: A population-based study.

BACKGROUND: It is established that comorbidities negatively influence colorectal cancer (CRC)-specific survival. Only few studies have used the relative survival (RS) setting to estimate this association, although RS has been proven particularly useful considering the inaccuracy in death certification. This study aimed to investigate the impact of non-cancer comorbidities at CRC diagnosis on net survival, using cancer registry data. METHODS: We included 1076 CRC patients diagnosed between 2000 and 2001 in the canton of Zurich. The number and severity of comorbidities was expressed using the Charlson Comorbidity Index (CCI). Multiple imputation was performed to account for missing information and 10-year net survival was estimated by modeling the excess hazards of death due to CRC, using flexible parametric models. RESULTS: After imputation, approximately 35 % of the patients were affected by comorbidities. These appeared to decrease the 10-year net survival; the estimated excess hazard ratio for patients with one mild comorbidity was 2.14 (95 % CI 1.60-2.86), and for patients with one more severe or more than one comorbidity was 2.43 (95 % CI 1.77-3.34), compared to patients without comorbidities. CONCLUSIONS: Our analysis suggested that non-cancer comorbidities at CRC diagnosis significantly decrease the 10-year net survival. Future studies should estimate net survival of CRC including comorbidities as prognostic factor and use a RS framework to overcome the uncertainty in death certification.

Risk for Invasive Cancers in Women With Breast Cancer In Situ: Results From a Population Not Covered by Organized Mammographic Screening.

BACKGROUND: Even though breast cancer in situ (BCIS) incidence has been increasing, the prognosis of BCIS patients has not been extensively investigated. According to the literature, women with BCIS have a higher risk of developing subsequent invasive breast cancer; conflicting information has been reported regarding their potential risk for a subsequent invasive non-breast cancer. METHODS: Data from 1,082 women, whose first-ever cancer diagnosis was primary BCIS between 2003 and 2015 and were living in the canton of Zurich, were used. Standardized incidence ratios (SIRs) were calculated to compare the risk of an invasive breast or non-breast cancer among women with a primary BCIS with the corresponding risk of the adult female population. SIRs were calculated overall and by patient and tumor characteristics. To investigate potential risk factors (e.g., age at diagnosis, treatment) for a subsequent invasive breast or non-breast cancer we used Cox proportional hazards regression models. RESULTS: BCIS patients had 6.85 times [95% confidence interval (CI): 5.52-8.41] higher risk of being diagnosed with invasive breast cancer compared to the general population. They additionally faced 1.57 times (95% CI: 1.12-2.12) higher risk of an invasive non-breast cancer. The SIRs were higher for women < 50-years old for both invasive breast and non-breast cancer at BCIS diagnosis. Age ≥ 70-years old at BCIS diagnosis was statistically significantly associated with a subsequent invasive non-breast cancer diagnosis. CONCLUSIONS: BCIS patients had a higher risk of being diagnosed with invasive breast and non-breast cancer compared to the general population. Age 70 years or older at BCIS diagnosis was the only risk factor statistically significantly associated with a subsequent invasive non-breast cancer. Our results support the increased risk for subsequent cancers in BCIS patients reported in the literature. Future studies should establish the risk factors for subsequent cancers, highlight the need for intensive monitoring in this population, and help distinguish BCIS patients who could benefit from systemic therapy to prevent distant cancers.

Are there sex differences among colorectal cancer patients in treatment and survival? A Swiss cohort study.

BACKGROUND: Colorectal cancer (CRC) is among the three most common incident cancers and causes of cancer death in Switzerland for both men and women. To promote aspects of gender medicine, we examined differences in treatment decision and survival by sex in CRC patients diagnosed 2000 and 2001 in the canton of Zurich, Switzerland. METHODS: Characteristics assessed of 1076 CRC patients were sex, tumor subsite, age at diagnosis, tumor stage, primary treatment option and comorbidity rated by the Charlson Comorbidity Index (CCI). Missing data for stage and comorbidities were completed using multivariate imputation by chained equations. We estimated the probability of receiving surgery versus another primary treatment using multivariable binomial logistic regression models. Univariable and multivariable Cox proportional hazards regression models were used for survival analysis. RESULTS: Females were older at diagnosis and had less comorbidities than men. There was no difference with respect to treatment decisions between men and women. The probability of receiving a primary treatment other than surgery was nearly twice as high in patients with the highest comorbidity index, CCI 2+, compared with patients without comorbidities. This effect was significantly stronger in women than in men (p-interaction = 0.010). Survival decreased with higher CCI, tumor stage and age in all CRC patients. Sex had no impact on survival. CONCLUSION: The probability of receiving any primary treatment and survival were independent of sex. However, female CRC patients with the highest CCI appeared more likely to receive other therapy than surgery compared to their male counterparts.

37-year incidence and mortality time trends of common cancer types by sex, age, and stage in the canton of Zurich.

AIMS OF THE STUDY: The Cancer Registry Zurich, Zug, Schaffhausen and Schwyz is one of the oldest cancer registries in Switzerland, first registering tumours in 1980 for the canton of Zurich. The aim of this study was to analyse trends in incidence and mortality for the most common types of cancer in the canton of Zurich from 1981 to 2017. METHODS: In this analysis of population-based cancer registry data, we included malignant tumours of the breast (ICD10 C50), prostate (C61), colon/rectum (C18–C21), lung (C33–C34), and melanoma (C43), diagnosed between 1981 and 2017. Age-standardised incidence and mortality rates per 100,000 person-years were computed using the 1976 European Standard Population. Incidence and mortality time trends were assessed using joinpoint regression analysis. RESULTS: In men, incidence for prostate cancer and melanoma increased over the study period, while it decreased for colon/rectum and lung cancer. A joinpoint for prostate cancer indicated the start of a decreasing trend in 2002. In women, incidence increased for breast cancer, lung cancer and melanoma; no trend was observed for colon/rectum cancer. Cancer mortality decreased for prostate, colon/rectum and lung cancer in men, with no clear trend for melanoma. In women, mortality decreased for breast cancer, colon/rectum cancer and melanoma, but increased for lung cancer. CONCLUSIONS: The overall increasing incidence trends for prostate and breast cancer, as well as for melanoma, are in line with data from other Western countries. While lung cancer incidence is decreasing in men, it is still on the rise in women. Despite increasing incidence rates, mortality rates are decreasing for all localisations except for lung cancer in women. The opposite direction of incidence and mortality curves is probably mostly due to better and more effective treatment options, as well as earlier detection.

Increasing trends in in situ breast cancer incidence in a region with no population-based mammographic screening program: results from Zurich, Switzerland 2003-2014.

PURPOSE: Increase in in situ breast cancer (BCIS) incidence has been reported across Europe and the USA. However, little is known about the trends in BCIS incidence in regions without population-based mammographic screening programs. We set out to investigate these trends in Zurich, Switzerland, where only opportunistic mammographic screening exists. METHODS: Data from 989 women diagnosed with a primary BCIS between 2003 and 2014 were used in our analyses. Age-standardized incidence rates per 100,000 person-years (ASR) were computed per year. Additional analyses by BCIS subtype, by age group at diagnosis and by incidence period were conducted. Incidence trends over time were assessed using joinpoint regression analysis. RESULTS: The overall BCIS ASR was 10.7 cases per 100,000 person-years with an increasing trend over the study period. A similar trend was observed for the ductal carcinoma in situ (DCIS) ASR, while the lobular carcinoma in situ (LCIS) ASR decreased. Age-specific analyses revealed that the 50-59 year age group had the highest BCIS ASR. The highest increase in BCIS ASR, even though not statistically significant, was observed for the < 40 year age group. CONCLUSIONS: BCIS ASR increased linearly over a 12-year period. The increase was reflected by an increase in DCIS ASR, whereas LCIS ASR decreased over time. The highest increase in BCIS ASR over the study period was observed for the < 40 year age group, even though not statistically significant. Patient and tumor characteristics of this group that may be associated with BCIS development warrant further investigation.

Impact of comorbidities at diagnosis on prostate cancer treatment and survival.

BACKGROUND: The aim of this study was to assess the associations of comorbidities with primary treatment of prostate cancer (PCa) patients and of comorbidities with PCa-specific mortality (PCSM) compared to other-cause mortality (OCM) in Switzerland. PATIENTS AND METHODS: We included 1527 men diagnosed with PCa in 2000 and 2001 in the canton of Zurich. Multiple imputation methods were applied to missing data for stage, grade and comorbidities. Multinomial logistic regression analyses were used to explore the associations of comorbidities with treatment. Cox regression models were used to estimate all-cause mortality, and Fine and Gray competing risk regression models to estimate sub-distribution hazard ratios for the outcomes PCSM and OCM. RESULTS: Increasing age was associated with a decreasing probability of receiving curative treatment, whereas an increasing Charlson Comorbidity Index (CCI) did not influence the treatment decision as strongly as age. The probability of OCM was higher for patients with comorbidities compared to those without comorbidities [CCI 1: hazard ratio 2.07 (95% confidence interval 1.51-2.85), CCI 2+: 2.34 (1.59-3.44)]; this was not observed for PCSM [CCI 1: 0.79 (0.50-1.23), CCI 2+: 0.97 (0.59-1.59)]. In addition, comorbidities had a greater impact on the patients' mortality than age. CONCLUSIONS: The results of the current study suggest that chronological age is a stronger predictor of treatment choices than comorbidities, although comorbidities have a larger influence on patients' mortality. Hence, inclusion of comorbidities in treatment choices may provide more appropriate treatment for PCa patients to counteract over- or undertreatment.

Primary Treatment Choice Over Time and Relative Survival of Prostate Cancer Patients: Influence of Age, Grade, and Stage.

BACKGROUND: The aim of this study was to assess associations of stage, grade, and age with the primary treatment of prostate cancer (PCa) patients comparing the incidence years 2000/2001 and 2012/2013, and to estimate the relative survival (RS) for patients diagnosed in 2000/2001. METHODS: We included 1,541 men diagnosed in 2000/2001 and 1,605 men diagnosed in 2012/2013. Multiple imputation methods were applied to missing data for stage and grade. Multinomial logistic regression analyses were used to explore the associations of stage, grade, and age with treatment. RS was estimated using the Ederer II approach. RESULTS: In 2000/2001, older patients were more likely to choose active surveillance (AS)/watchful waiting (WW) or to receive androgen deprivation therapy (ADT) compared to surgery; in 2012/2013, this association was only observed for ADT but not for AS/WW. In 2000/2001, the overall 1-, 5-, and 10-year RS was approximately 99, 94, and 92%, respectively. RS was highest for patients who underwent surgical procedures or radiotherapy and considerably lower for patients with ADT. CONCLUSION: Our data show that today AS/WW is an option not only for patients with a life expectancy of < 10 years but also for younger men with localized PCa. PCa patients have a good RS if the cancer is diagnosed at an early stage.