Cancer Epidemiology最新文献

Introduction: Smoking is a strong modifiable prognostic factor for lung cancer survival. We compared eight smoking metrics to determine which metric best models the relationship between smoking exposure with overall survival (OS) and lung cancer-specific survival (LCSS). These metrics included cigarettes-per-day, smoking duration, pack-years, square-root pack-years, logcig-years, the comprehensive smoking index, age-of-initiation, and years-since-quit.

Materials/methods: This retrospective, pooled analysis included 25 International Lung Cancer Consortium studies between June 1, 1983-December 31, 2019. The performance of smoking metrics for modelling OS was compared based on 1) strength and significance in adjusted Cox-proportional hazard models and 2) linearity based on the goodness-of-fit assuming the log-hazard varies linearly with each smoking metric (i.e. the hazard ratio is constant across different values of the smoking metric) compared to models using non-linear splines. This process was repeated across clinicodemographic subgroups and for LCSS.

Results: In total, 28,702 lung cancer patients were included (median age 64 [IQR: 57-71]; 53% male). Logcig-years (log(cigarettes/day+1)·years-smoked) had the highest adjusted hazard ratio per standard deviation (aHR 1.11; 95% CI: 1.09-1.13) and best goodness-of-fit when modelled linearly. Square-root pack-years had a similar effect size (aHR 1.11; 95% CI: 1.09-1.13) and had a strong linear relationship on visual assessment of spline curves. In subgroup analyses, logcig-years had a large effect size and maintained a linear relationship regardless of age, sex, stage, and histology. For lung cancer-specific survival (LCSS), logcig-years again had the highest aHR (1.09; 95% CI: 1.05-1.12) and the best linear goodness-of-fit, while square-root pack-years demonstrated the most linear relationship on visual assessment.

Discussion: Logcig-years best modelled the relationship between smoking exposure and OS as well as LCSS, and had consistent associations across clinicodemographic subgroups. Logcig-years should be considered in clinical and research applications for quantifying smoking exposure in lung cancer.

Background: Most existing evidence on secondhand smoke (SHS) exposure and lung cancer in never-smoking women comes from case-control studies, while findings from prospective cohort studies remain inconsistent. Regional variation in SHS-associated risk is poorly understood, and the potential impact of reducing SHS exposure in never-smoking women has not been quantified.

Methods: We analyzed data from 20,401 never-smoking women in the Wenling lung cancer screening cohort (Zhejiang, China), applying Cox proportional hazards regression models to evaluate the association between SHS exposure and lung cancer risk. We further conducted a meta-analysis of published studies to examine regional variation and estimated the population attributable fraction (PAF) of SHS exposure for lung cancer incidence in never-smoking women.

Results: SHS exposure was associated with an increased lung cancer risk (HR=1.52, 95% CI: 1.19-1.95). Lung cancer risk tended to increase with higher smoking intensity, with a linear trend observed for cigarettes per day, years of smoking, and pack-years of co-residents and colleagues (P_overall<0.05; P_non-linear>0.05). In meta-analysis, the pooled relative risk was higher in Asia than in Europe and America [RR= 1.31 (95% CI: 1.20-1.43) vs 1.13 (95% CI: 1.04-1.23); P_het = 0.039]. The PAF suggested that 16.9% (95% CI: 11.6%-22.0%) of lung cancer cases among never-smoking women could be attributed to SHS exposure.

Conclusions: SHS exposure is a risk factor for lung cancer in never-smoking women, with stronger effects observed in Asian populations. Reducing SHS exposure could prevent a substantial proportion of lung cancer cases, underscoring the urgent need for strengthened tobacco control policies.

Background: Bladder cancer is a neoplasm with a higher prevalence in men and older adults. In Colombia, it accounts for approximately 1% of all cancer cases, with a marked difference between sexes (1.6% in men vs. 0.5% in women).

Objective: To determine the incidence, mortality, and 5-year relative survival (RS5) of bladder cancer in six population-based cancer registries (PBCRs) in Colombia, 2003-2018.

Methods: This retrospective observational study employed data from six population-based cancer registries (Barranquilla, Bucaramanga, Cali, Manizales, Medellín, Pasto). Crude and age-standardized incidence and mortality rates were calculated by the direct method using the Segi world standard population. Trends were evaluated using Joinpoint regression (Annual Percent Change, APC). RS5 was estimated using the Pohar-Perme method. Analyses were stratified by sex, age, PBCR, and histological subtype.

Results: During the study period, 3019 cases were registered (69.9% male, 30.1% female). The incidence was 2.3 times higher in men compared to women, with age-standardized rates ranging from 4.3 to 6.8 per 100,000, increasing sharply after the age of 55. Urothelial carcinoma of the bladder (UCB) was the most frequent subtype (77.9%), followed by the unspecified category (16.7%), adenocarcinoma (2.2%), and squamous cell carcinoma (1.9%). For the survival analysis (n = 2066, excluding Cali), RS5 varied significantly across registries, ranging from 42.6% (Pasto) to 83.7% (Medellín). In all registries, NS5 was consistently higher in men than in women.

Conclusion: Bladder cancer in Colombia showed a marked male predominance, with incidence increasing sharply after the sixth decade of life. The urothelial subtype was the most frequent and exhibited the most prognosis among the reported cases.

Introduction: Chronic pancreatitis (CP) is driven by smoking, excessive alcohol use, and chronic inflammation - all known contributors to carcinogenesis. However, its association with malignancies beyond the pancreas remains underexplored. This study aimed to assess the frequency and spectrum of cancers in patients with CP.

Method: A retrospective cohort study was conducted at Nottingham University Hospitals of patients diagnosed with CP between 1 January 2006 and 31 December 2014, identified through a multisource case ascertainment strategy. Cancer frequencies were assessed in patients residing within Greater Nottingham. Age-adjusted standardised incidence ratios (SIRs) were calculated using national cancer incidence data from England as the reference population. Statistical analyses were performed using R (version 4.3.3).

Results: Of the 1003 CP patients identified, 678 resided in Greater Nottingham (median age at diagnosis 68 years (IQR 53-79); 66% male; 92% Caucasians. The median follow-up period was 7.3 years (IQR 2.8-11.6). Compared to the general population, patients with CP demonstrated significantly higher SIRs for upper respiratory tract (12.4; 95%CI 6.6-21.1; p < 0.0001), pancreatic (10.8; 95%CI 6.2-17.6; p < 0.0001), liver (8.8; 95%CI 2.4-22.6; p < 0.0001), lung (5.6; 95%CI 4.0-7.7; p < 0.0001), renal tract (4.8; 95%CI 2.7-7.9; p < 0.0001) oesophageal (4.8; 95%CI 1.8-10.4; p = 0.0001) and colorectal (2.5; 95%CI 1.4-4.2; p = 0.0009) cancers.

Conclusion: CP confers a markedly elevated risk of both pancreatic and extra-pancreatic cancers. These findings hypothesise that CP might be a high-risk state for malignancy that could warrant proactive, risk-based cancer surveillance in this vulnerable population.