Risk of lung cancer among women in relation to lifetime history of tobacco smoking: a population-based case-control study in France (the WELCA study)

Fat intake modifies association between cigarette smoking and lung cancer in a prospective cohort study: A potential explanation for the lung cancer paradox

BACKGROUND & AIMS

It remains unclear why the association between cigarette smoking and lung cancer was substantially stronger in Western countries than in Asian countries. As experimental studies have revealed that fat intake modulates tobacco carcinogen metabolism and the growth of transplanted or carcinogen-induced lung tumors in mice, the present study sought to investigate whether the association between cigarette smoking and lung cancer was modified by intake of total fat and types of fat (saturated, monounsaturated, and polyunsaturated fats) in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.

METHODS

During a median follow-up of 8.9 years, 1,425 cases of lung cancer were documented from 100,864 participants eligible for the present analysis. Cox proportional hazards regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

After adjustment for established or suspected confounders, the strength of the association between cigarette smoking and lung cancer was remarkably larger among individuals with high fat intake. HRs (95% CIs) comparing current with never smokers were 23.0 (13.4, 39.6), 32.7 (20.3, 52.8), and 59.8 (30.2, 118.2) for the tertile 1 (≤13.48 g/day), tertile 2 (13.49-21.89 g/day), and tertile 3 (≥21.90 g/day) of saturate fat intake, respectively. A similar pattern of the non-significant interaction was observed when the accumulated amount of cigarette smoking (1-19, 20-39, and ≥40 vs. 0 pack-years) was entered into the regression models.

CONCLUSIONS

The present study showed that lung cancer risk associated with both the status and accumulated amount of cigarette smoking was remarkably stronger in individuals with high intakes of fat, particularly saturated fat. However, this interaction was not statistically significant and thus warrants further investigations in other studies.

Characteristics and patient-reported outcomes of long-term lung cancer survivors

Background

Due to advances in screening and treatment of lung cancer, there has been increased interest in long-term lung cancer survivors (LTLCS). The aim of this study was to evaluate the prevalence of LTLCS, their characteristics and patient-reported outcomes (PROs) of LTLCS.

Methods

Cross-sectional study that included patients diagnosed with primary lung cancer between Jan 2012 and Dec 2016 whose overall survival (OS) was greater than 5 years. A self-administered questionnaire was applied, including European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core-30 (EORTC QLQ-C30), Patient Health Questionnaire-4 (PHQ-4) and two open questions regarding quality of life (QoL) and suggestions for improvements. Factors potentially related to QoL were analysed.

Results

Of 767 lung cancer patients, 158 (20.6%) were LTLCS and LTLCS' proportion increased yearly. Most patients were male (70.9%) with median age of 65 [interquartile range (IQR), 56-71] years. Fifty-seven percent had adenocarcinoma, 66.2% were diagnosed at early stages but 8.9% were at stage IV. During follow-up, 77.1% quitted smoking, 31.8% had disease progression/relapse and 15.2% developed other tumours. Of all living LTLCS, 100 (85%) patients answered the PROs questionnaire. The median Global Health score was 66.67 (IQR, 50-83), social functioning had the best score and emotional functioning the worst. Pain and fatigue were the symptoms with the worst impact on QoL. PHQ-4 identified mental distress in 36% and patients with a lower QoL were more likely to present anxiety (35.3% vs. 9.4%, P=0.007) or depression (27.9% vs. 3%, P=0.006). In the open questions, patients reported pain (17%), lack of familiar/financial support (16%), dyspnoea (14%), depression (8%), concern for the future (8%) and limitations performing daily activities (8%) as the aspects with most impact in QoL. The most suggested measures were improvement of care provided by health institutions (25%) and better social support (16%).

Conclusions

Prevalence of LTLCS is increasing and survivors may experience a high prevalence of anxiety and depression as well as a high disease burden affecting QoL. Therefore, it's important to provide multidisciplinary continuous patient-centred care and a careful follow-up for all lung cancer patients, including LTLCS.

Impacts of ezetimibe on risks of various types of cancers: a meta-analysis and systematic review

BACKGROUND

Ezetimibe is a widely used medication to reduce the plasma cholesterol level, particularly low-density lipoprotein level. However, its impact on cancer remains controversial. Here, its impacts on risks of various types of cancers were meta-analyzed.

METHODS

PubMed and Cochrane Library electronic databases were searched and randomized controlled trials with followed up for at least 24 weeks were selected and included. The experimental group was defined as those patients treated with ezetimibe alone or with other medications, and the control group was defined as those who received a placebo or the matched medication. The number of new cancer cases or cancer-related deaths was extracted. Statistical analysis was performed using Review Manager (version 5.3).

RESULTS

Nine trials enrolling 35 222 patients were included in the analyses. Compared with the control group, ezetimibe increased the number of new intestine cancer patients [relative risk (RR), 1.30; 95% confidence interval (CI), 1.02-1.67; P  = 0.03] and had a trend to increase the number of new breast cancer patients (RR, 1.39; 95% CI, 0.98-1.98; P  = 0.07). There was no significant difference in new hepatobiliary cancer, prostate cancer, skin cancer or cancer of other sites. Ezetimibe did not significantly increase the risk of new cancer in total (RR, 1.03; 95% CI, 0.96-1.11; P  = 0.38), cancer-related death (RR, 1.11; 95% CI, 0.98-1.26; P  = 0.10) or cancer events (RR, 1.04; 95% CI, 0.97-1.12; P  = 0.30). In terms of lipid-lowering effect, ezetimibe significantly reduced total cholesterol and low-density lipoprotein cholesterol, increased high-density lipoprotein cholesterol.

CONCLUSION

Ezetimibe may increase the risk of intestine cancer and has a trend of increasing the risk of breast cancer. There is no evidence to support that it increases or decreases the risk of other types.

Longitudinal Changes in Smoking Habits in Women and Subsequent Risk of Cancer

INTRODUCTION

This study investigated the association between longitudinal smoking habit changes and cancer risk in a cohort of Korean women.

METHODS

Study population included women aged ≥40 years who underwent 2 biennial cancer screenings (2009-2010 and 2011-2012) and were followed up until 2020. This analysis was conducted in 2021. On the basis of changes in smoking habits, participants were grouped into sustained nonsmokers, sustained quitters, new quitters, relapsers, smoking initiators, and sustained smokers. Outcomes included incident cancer cases, smoking-related cancers, and specific cancer sites.

RESULTS

Of 3,051,946 women, the mean age was 54.8 years, and the median follow-up was 8.9 years. Compared with sustained nonsmokers, other groups had a significantly increased risk of cancer and smoking-related cancers: sustained quitters (adjusted hazard ratio=1.05; 95% CI=1.01, 1.09), new quitters (adjusted hazard ratio=1.12; 95% CI=1.07, 1.17), and sustained smokers (adjusted hazard ratio=1.14; 95% CI=1.09, 1.19). A significantly increased risk of lung, stomach, liver, and pancreas cancers was found in sustained smokers and new quitters. Relapsers/smoking initiators showed a higher risk of liver, lung, and breast cancer than sustained nonsmokers, but the strength of their corresponding adjusted hazard ratio was generally lower than that of sustained smokers. The hazard ratio of cancer risk was 0.92 (95% CI=0.87, 0.97) among sustained quitters and 0.97 (95% CI=0.91, 1.03) among new quitters relative to that among sustained smokers.

CONCLUSIONS

This study found a significant association between changes in smoking behavior and cancer risk. These findings suggest that smoking cessation is critical for cancer prevention in women.

The Potential Role of MUC16 (CA125) Biomarker in Lung Cancer: A Magic Biomarker but with Adversity

Lung cancer is the second most commonly diagnosed cancer in the world. In terms of the diagnosis of lung cancer, combination carcinoembryonic antigen (CEA) and cancer antigen 125 (CA125) detection had higher sensitivity, specificity, and diagnostic odds ratios than CEA detection alone. Most individuals with elevated serum CA125 levels had lung cancer that was either in stage 3 or stage 4. Serum CA125 levels were similarly elevated in lung cancer patients who also had pleural effusions or ascites. Furthermore, there is strong evidence that human lung cancer produces CA125 in vitro, which suggests that other clinical illnesses outside of ovarian cancer could also be responsible for the rise of CA125. MUC16 (CA125) is a natural killer cell inhibitor. As a screening test for lung and ovarian cancer diagnosis and prognosis in the early stages, CA125 has been widely used as a marker in three different clinical settings. MUC16 mRNA levels in lung cancer are increased regardless of gender. As well, increased expression of mutated MUC16 enhances lung cancer cells proliferation and growth. Additionally, the CA125 serum level is thought to be a key indicator for lung cancer metastasis to the liver. Further, CA125 could be a useful biomarker in other cancer types diagnoses like ovarian, breast, and pancreatic cancers. One of the important limitations of CA125 as a first step in such a screening technique is that up to 20% of ovarian tumors lack antigen expression. Each of the 10 possible serum markers was expressed in 29-100% of ovarian tumors with minimal or no CA125 expression. Therefore, there is a controversy regarding CA125 in the diagnosis and prognosis of lung cancer and other cancer types. In this state, preclinical and clinical studies are warranted to elucidate the clinical benefit of CA125 in the diagnosis and prognosis of lung cancer.

Health effects associated with smoking: a Burden of Proof study

As a leading behavioral risk factor for numerous health outcomes, smoking is a major ongoing public health challenge. Although evidence on the health effects of smoking has been widely reported, few attempts have evaluated the dose-response relationship between smoking and a diverse range of health outcomes systematically and comprehensively. In the present study, we re-estimated the dose-response relationships between current smoking and 36 health outcomes by conducting systematic reviews up to 31 May 2022, employing a meta-analytic method that incorporates between-study heterogeneity into estimates of uncertainty. Among the 36 selected outcomes, 8 had strong-to-very-strong evidence of an association with smoking, 21 had weak-to-moderate evidence of association and 7 had no evidence of association. By overcoming many of the limitations of traditional meta-analyses, our approach provides comprehensive, up-to-date and easy-to-use estimates of the evidence on the health effects of smoking. These estimates provide important information for tobacco control advocates, policy makers, researchers, physicians, smokers and the public.

Transcription Factor MAFB as a Prognostic Biomarker for the Lung Adenocarcinoma

MAFB is a basic leucine zipper (bZIP) transcription factor specifically expressed in macrophages. We have previously identified MAFB as a candidate marker for tumor-associated macrophages (TAMs) in human and mouse models. Here, we analyzed single-cell sequencing data of patients with lung adenocarcinoma obtained from the GEO database (GSE131907). Analyzed data showed that general macrophage marker CD68 and macrophage scavenger receptor 1 (CD204) were expressed in TAM and lung tissue macrophage clusters, while transcription factor MAFB was expressed specifically in TAM clusters. Clinical records of 120 patients with lung adenocarcinoma stage I (n = 57), II (n = 21), and III (n = 42) were retrieved from Tsukuba Human Tissue Biobank Center (THB) in the University of Tsukuba Hospital, Japan. Tumor tissues from these patients were extracted and stained with anti-human MAFB antibody, and then MAFB-positive cells relative to the tissue area (MAFB+ cells/tissue area) were morphometrically quantified. Our results indicated that higher numbers of MAFB+ cells significantly correlated to increased local lymph node metastasis (nodal involvement), high recurrence rate, poor pathological stage, increased lymphatic permeation, higher vascular invasion, and pleural infiltration. Moreover, increased amounts of MAFB+ cells were related to poor overall survival and disease-free survival, especially in smokers. These data indicate that MAFB may be a suitable prognostic biomarker for smoker lung cancer patients.

Excess Body Weight and Long-Term Incidence of Lung and Colon Cancer in Men; Follow-Up Study of 43 Years

Most evidence for an association between excess body weight and cancer risk has been derived from studies of relatively short duration with little reference to the effect on tumor site. This study was designed to evaluate the association between categories of body mass index (BMI: <20, 20–25, 25–30, and >30 kg/m²) and the incidence of colon and lung cancer over 43 years of follow-up (1963–2006), in 10,043 men from the Israeli Ischemic Heart Disease (IIHD) prospective cohort (mean age at baseline 49.3 years, mean BMI 25.7 kg/m²). Data from the Israel National Cancer Registry was linked with the IIHD, and the Cox proportional hazards regression model was applied to analyze the relative risks for lung and colon cancer across BMI categories at baseline. Three hundred cases of lung cancer (2.9%) and 328 cases of colon cancer (3.3%) were diagnosed in the total population. Applying a multivariate model adjusted for age, smoking intensity, and total cholesterol, higher BMI category was associated with an increased risk of colon cancer [HR = 1.22 (95% CI 1.02–1.45)], and with a decreased risk for lung cancer [HR = 0.66 (95% CI 0.56–0.77)]. In this long-term follow-up study over four decades, we observed a consistent dose-response pattern between BMI and increased risk for colon cancer, but decreased risk for lung cancer. Specific associations between excess body weight and cancer risk may suggest different patterns of body fat and cancer incidence at a given site.