Body mass index and mortality from lung cancer in smokers and nonsmokers: A nationally representative prospective study of 220,000 men in China

Lung cancer mortality and associated predictors: systematic review using 32 scientific research findings

Background

Cancer is a chronic disease brought on by mutations to the genes that control our cells' functions and become the most common cause of mortality and comorbidities. Thus, this study aimed to assess the comprehensive and common mortality-related risk factors of lung cancer using more than thirty scientific research papers.

Methods

Possible risk factors contributing to lung cancer mortality were assessed across 201 studies sourced from electronic databases, including Google Scholar, Cochrane Library, Web of Science (WOS), EMBASE, Medline/PubMed, the Lung Cancer Open Research Dataset Challenge, and Scopus. Out of these, 32 studies meeting the eligibility criteria for meta-analysis were included. Due to the heterogeneous nature of the studies, a random-effects model was applied to estimate the pooled effects of covariates.

Results

The overall prevalence of mortality rate was 10% with a 95% confidence interval of 6 and 16%. Twenty studies (62.50%) studies included in this study considered the ages of lung cancer patients as the risk factors for mortality. Whereas, eighteen (56.25%) and thirteen (40.63%) studies incorporated the gender and smoking status of patients respectively. The comorbidities of lung cancer mortality such as cardiovascular disease, hypertension, diabetes, and pneumonia were also involved in 7 (21.90%), 6 (18.75%), 5 (15.63%), and 2 (6.25%) studies, respectively. Patients of older age are more likely to die as compared to patients of younger age. Similarly, lung patients who had smoking practice were more likely to die as compared to patients who hadn't practiced smoking.

Conclusion

The mortality rate of lung cancer patients is considerably high. Older age, gender, stage, and comorbidities such as cardiovascular, hypertension, and diabetes have a significant positive effect on lung cancer mortality. The study results will contribute to future research, management, and prevention strategies for lung cancer.

Obesity Does Not Increase Perioperative Outcomes in Older Patients Undergoing Thoracoscopic Anatomic Lung Cancer Surgery

Objectives

To investigate the relationship between obesity status and perioperative outcomes in elderly patients undergoing thoracoscopic anatomic lung cancer surgery.

Methods

From January 2016 to December 2018, we performed a monocentric retrospective cohort study among 4164 consecutive patients aged 65 years or older who underwent thoracoscopic anatomic lung cancer surgery at Shanghai Chest Hospital. Two groups were stratified by body mass index (BMI): nonobese (BMI<28kg/m²) and obese status (BMI≥28kg/m²). Using a 1:1 propensity score matching (PSM) analysis to compare perioperative outcomes between two groups.

Results

4035 older patients were eventually enrolled, with a mean age of 69.8 years (range: 65-87), and 305 patients were eligible for obese status, with a mean BMI of 29.8 ± 1.7kg/m². Compared with nonobese patients, obese patients were more likely to have higher rates of intraoperative hypoxemia (1.2% vs 3.9%, P=0.001) and new-onset arrhythmia (2.3% vs 4.3%, P=0.034). The difference in intraoperative transfusion and conversion rates and postoperative outcomes regarding pulmonary complications, new-onset arrhythmia, transfusion, length of hospital stay, 30-day readmission and hospitalization costs between two groups were not significant (P>0.05). After a 1:1 PSM analysis, the difference in both intraoperative and postoperative complications among two groups were not significant (P>0.05). In subgroup analysis, patients with BMI≥30kg/m² had a similar incidence of perioperative complications compared to patients with BMI between 28 and 30 kg/m² (P>0.05).

Conclusions

Our research data support evidence for “obesity paradox” and also contribute the growing body of evidence that obesity in older patients should not exclude candidates for thoracoscopic anatomic lung cancer surgery.

Impact of body mass index on perioperative and oncological outcomes in elderly patients undergoing minimally invasive McKeown esophagectomy for esophageal squamous cell carcinoma

Background

The association between elevated body mass index (BMI) and perioperative and oncological outcomes among elderly patients undergoing minimally invasive McKeown esophagectomy (MIE) remains unclear.

Methods

We performed a single‐center retrospective analysis of 526 consecutive patients aged 65 years or older who underwent MIE for esophageal squamous cell carcinoma (SCC) between January 2016 and December 2019. Two groups were stratified by BMI: normal (18.5 ≤ BMI < 24 kg/m²) and elevated groups (BMI ≥ 24 kg/m²). A 1:1 propensity score matching (PSM) analysis was used to compare perioperative and oncological outcomes between the two groups.

Results

A total of 480 elderly patients were eventually enrolled, with a mean age of 70.2 years (range: 65–87), and 185 patients were eligible for elevated BMI, with a mean BMI of 26.3 ± 1.9 kg/m². Compared with the normal BMI group, the elevated BMI group had prolonged operation time (261.7 ± 57.2 vs. 278.9 ± 62.7 mins, p = 0.002) and increased incidence of intraoperative hypoxemia (12.2% vs. 21.6%, p = 0.006). The differences in intraoperative estimated blood loss, transfusion, new‐onset arrhythmia, and conversion rates and postoperative outcomes regarding pulmonary and surgical complications, intensive care unit and 30‐day readmissions, the length of hospital stay, and oncological outcomes regarding R0 dissection, and the number of dissected lymph nodes between two groups were comparable. After a 1:1 PSM analysis, there was no significant difference in both perioperative and oncological outcomes between two groups.

Conclusions

Among elderly patients undergoing MIE for esophageal SCC, there was insufficient evidence to demonstrate that elevated BMI could increase perioperative and oncological adverse outcomes.

Body Mass Index, Height, Weight Change, and Subsequent Lung Cancer Risk: The Japan Public Health Center-Based Prospective Study

BACKGROUND

Body mass index (BMI) is inversely associated with lung cancer risk, while residual confounding by smoking or weight change is controversial. Evidence on height and lung cancer is scarce.

METHODS

We investigated the associations between anthropometrics, BMI, and height, and incidence of lung cancer among 92,098 study subjects (44,158 men and 47,940 women) in the Japan Public Health Center-based Prospective Study. Cox proportional hazards regression was performed with adjustment for potential confounders and by cancer subtypes and smoking status. Information on weight and height was self-reported at baseline, and validated using measured health check-up data.

RESULTS

During follow-up between 1990 and 2013 (average, 19.1 years), a total of 2,152 lung cancer cases were newly diagnosed. In a multivariate regression model, lower BMI was positively associated with overall lung cancer risk [<19 kg/m² HR = 1.48; 95% confidence interval (CI) = 1.18-1.85 and 19-22.9 kg/m²; HR = 1.19; 95% CI = 1.05-1.35; P _trend = <0.001] in men. The risk estimate was also elevated for adenocarcinoma in the BMI <19 kg/m² category and for squamous cell carcinoma among men in the 19-22.9 kg/m² BMI category. An association was also observed between low BMI, weight decrease, and squamous cell carcinoma in women. No significant associations were observed for other weight categories, height, weight change and lung cancer, adenocarcinoma, squamous and small cell carcinoma.

CONCLUSIONS

Our prospective study suggests that lower BMI may be associated with an increased risk of smoking-related lung cancer in Japan, irrespective of gender.

IMPACT

This study highlights the association between lower BMI and the risk of lung cancer in men.

Obesity, Sarcopenia, and Outcomes in Non-Small Cell Lung Cancer Patients Treated With Immune Checkpoint Inhibitors and Tyrosine Kinase Inhibitors

Body composition refers to the proportional content of body fat mass and lean body mass that can lead to a continuum of different phenotypes ranging from cachectic/sarcopenic state to obesity. The heterogenetic phenotypes of body composition can contribute to formation of some cancer types and can sometimes lead to disparate outcomes. Both of these extremes of the spectrum exist in patients with non-small cell lung carcinoma (NSCLC). The discovery of new pathways that drive tumorigenesis contributing to cancer progression and resistance have expanded our understanding of cancer biology leading to development of new targeted therapies including tyrosine kinase inhibitors (TKI) and immune checkpoint inhibitors (ICI) that have changed the landscape of NSCLC treatment. However, in the new era of precision medicine, the impact of body composition phenotypes on treatment outcomes and survival is now being elucidated. In this review, we will discuss the emerging evidence of a link between body composition and outcomes in patients with NSCLC treated with TKI and ICI. We will also discuss suggested mechanisms by which body composition can impact tumor behavior and anti-tumor immunological response.

A three serum miRNA panel as diagnostic biomarkers of radiotherapy-related metastasis in non-small cell lung cancer

Serum microRNAs (miRNAs) have been implicated as noninvasive biomarkers for lung cancer diagnosis. However, there are no sensitive and specific biomarkers for the detection of radiotherapy-related non-small cell lung cancer (NSCLC) metastasis. The present study aimed to investigate the role of three serum miRNAs, namely miRNA (miR)-130a, miR-25 and miR-191*, in diagnosing NSCLC, and their biological functions in radiation-mediated development of metastatic properties in A549 cells. To determine this, serum samples were collected from 84 patients with NSCLC and 42 age- and sex-matched healthy controls. Differential expression of serum miRNAs was analyzed by quantitative PCR. Significant associations between miRNA expression and overall survival of patients with NSCLC were identified using the Cox proportional regression model. A receiver operating characteristic curve was generated to evaluate diagnostic accuracy. The functions of miR-130a, miR-25 and miR-191* in lung cancer cells were studied by transfecting A549 cells with miRNA mimics and inhibitors. The results of the present study demonstrated that the expression levels of miR-130a, miR-25 and miR-191* in the serum of patients with NSCLC were increased compared with those in healthy controls, and these increases were associated with advanced age (≥60 years), radiotherapy, histological type (squamous carcinoma), low survival rate and low median survival time. Additionally, irradiation induced the upregulation of miR-130a, miR-25 and miR-191* expression in A549 cells in vitro and in a xenograft mouse model. Irradiation also promoted the invasiveness of A549 cells in vitro and metastasis in vivo. In conclusion, miR-130a, miR-25 and miR-191* may be potential biomarkers for the diagnosis of patients with NSCLC and may serve oncogenic roles in radiation-mediated metastasis of NSCLC.

Prevalence of low body mass index among newly diagnosed lung cancer patients in North India and its association with smoking status

There is limited data from South Asia on the prevalence of low body mass index (BMI) among newly diagnosed lung cancer patients at presentation and its association with smoking status. A retrospective analysis of a prospective cohort of newly diagnosed lung cancer patients is presented here. Patients were categorized as normal/overweight (BMI ≥ 18.50 kg/m² ; group I), mild/moderately underweight (BMI = 16.00-18.49 kg/m² ; group II) or severely underweight (BMI < 16.0 kg/m² ; group III). Smoking status was assessed using the smoking index (SI; product of number of bidis/cigarettes smoked per day with number of years smoked). Based on the SI, patients were categorized as never-smokers, light/moderate smokers [SI = 1-300] and heavy smokers [SI ≥ 301]. A low BMI was present in 155 (44.3%) patients. Compared to group I, patients in groups II and III had higher percentages of men and current/ex-smokers. On univariate logistic regression analysis (LRA), SI = 1-300 [odds ratio (OR) = 2.75; 95% confidence intervals (CI) = 1.27-5.97] and SI ≥ 301 [OR = 4.57; 95% CI = 2.20-9.49] were associated with higher odds of the presence of low BMI among non-small cell lung cancer (NSCLC) patients while female sex had lower odds [OR = 0.34; 95% CI = 0.16-0.72]. On multivariate LRA, only SI ≥ 301 [OR = 3.74; 95% CI = 1.59-8.80] had a significant association with occurrence of low BMI. Low BMI is common among newly diagnosed lung cancer patients in North India. Heavy smoking is independently associated with presence of low BMI at presentation among NSCLC patients.

Combining serum miRNAs, CEA, and CYFRA21-1 with imaging and clinical features to distinguish benign and malignant pulmonary nodules: a pilot study : Xianfeng Li et al.: Combining biomarker, imaging, and clinical features to distinguish pulmonary nodules

BACKGROUND: Our study was designed to improve the accuracy of determining whether pulmonary nodules are benign or malignant.

METHODS

We evaluated the clinical and imaging features and serum markers: neuron specific enolase (NSE), carcino-embryonic antigen (CEA), cytokeratin fragment antigen 21-1 (CYFRA 21-1), miRNA-21-5p, and miR-574-5pof in 39 patients with pathology information. Factors that differed significantly between those with benign versus malignant pulmonary nodules were used to establish a prediction model for identifying malignant nodules.

RESULTS

The studied nodules were 51.3% malignant and 48.7% benign. Age, smoking status, nodule diameter, history of emphysema, vascular sign, burr sign, CYFRA21-1, CEA, miRNA-21-5p, and miRNA-574-5p differed significantly between the benign and malignant nodule groups. Serum levels of CYRFA21-1 and CEA could be used to distinguish between malignant and benign nodules with a positive predictive value (PPV) of 80.0%, a negative predictive value (NPV) of 84.2%, and an area under the receiver operating characteristics curve (AUC) of 0.863. Using the serum levels of miRNA-21-5p and miRNA-574-5p, the PPV was 55%, the NPV was 84.2%, and the AUC was 0.797. When all four serum markers were combined, the PPV was 80%, the NPV was 89.5%, and the AUC was 0.921. We established a prediction model for malignant nodules, including clinical features, imaging features, and serum markers. In cross-validation, the ratio of discriminant conformance was 95%.

CONCLUSIONS

Serum levels of miRNA-21-5p and miRNA-574-5p are significantly higher in patients with malignant nodules than in patients with benign nodules and are potential serum biomarkers. Our prediction model could improve malignant nodule diagnosis.

Body mass index and mortality in lung cancer patients: a systematic review and meta-analysis

Studies examining the relation of body mass index (BMI) and mortality in patients with lung cancer have shown diverse results. We conducted a meta-analysis to investigate the association using all available studies from January 1982 to October 2016. PubMed and EMBASE were searched to identify relevant studies. We calculated the summary hazard ratio (HR) and 95% confidence interval (CI) using random effects model. The dose-response relationship was assessed by random effects meta-regression model. Fifty-five articles from 51 studies involving 3 152 552 subjects (males, 54.8%) were included. The pooled results suggested that on average a high BMI decreased risk of death from lung cancer or all-cause. Each 5 kg/m² increase in BMI had a 12% lower risk of lung cancer-specific mortality (HR=0.88, 95% CI: 0.75-1.02, P=0.09) and a 14% lower risk of all-cause mortality (HR=0.86, 95% CI: 0.77-0.96, P<0.01). When stratifying by ethnicity, each 5 kg/m² increase in BMI was associated with 22% and 28% reduction, respectively, in the risk of lung cancer-specific mortality (P<0.01) and all-cause mortality (P<0.01) in Asians, but no association was found in Westerners (P=0.51 and P=0.53, respectively). In conclusion, lung cancer patients with a higher BMI have a longer survival than those with a lower BMI. Considering the significant heterogeneity between included studies, future studies are needed to confirm these findings.

Effect of body mass index on survival of patients with stage I non-small cell lung cancer

Background

Body mass index (BMI) has a U-shaped association with lung cancer risk. However, the effect of BMI on prognosis is controversial. This retrospective study aimed to investigate the effect of BMI on the survival of patients with stage I non-small cell lung cancer (NSCLC) after surgical resection.

Methods

In total, 624 consecutive stage I NSCLC patients who underwent radical resection were classified into four groups according to their BMI: underweight (BMI < 18.5 kg/m²), normal weight (BMI = 18.5–22.4 kg/m²), overweight (BMI = 22.5–28.0 kg/m²), and obese (BMI > 28.0 kg/m²). The effect of BMI on progression-free survival (PFS) and overall survival (OS) was estimated using the Kaplan–Meier method and Cox proportional hazards model. Postoperative complications in each group were analyzed using the Chi square test or Fisher’s exact test.

Results

A univariate analysis showed that PFS and OS were longer in the overweight group than in other groups (both P < 0.05). A multivariate analysis showed that OS was longer in the overweight group than in other groups (compared with the other three groups in combination: hazard ratio [HR] = 1.87, 95% confidence interval [CI] 1.30–2.68, P = 0.003; compared with the underweight group: HR = 2.24, 95% CI 1.18–4.25, P = 0.013; compared with the normal weight group: HR = 1.58, 95% CI 1.07–2.33, P = 0.022; compared with the obese group: HR = 2.87, 95% CI 1.48–5.59, P = 0.002), but PFS was similar among the groups (HR = 1.28, 95% CI 0.97–1.68, P = 0.080). A subgroup analysis showed an association between being overweight and prolonged OS in patients at stage T1a (P = 0.024), T1b (P = 0.051), and T2a (P = 0.02), as well as in patients with a non-smoking history (P = 0.001). Overweight patients had lower rates of postoperative complications, such as respiratory failure (compared with the underweight and obese groups: P = 0.014), myocardial infarction (compared with the obese group: P = 0.033), and perioperative death (compared with the other three groups: P = 0.016).

Conclusions

Preoperative BMI is an independent prognostic factor for stage I NSCLC patients after resection, with overweight patients having a favorable prognosis.

EGFR mutations in non-small cell lung cancer: an audit from West China Hospital

OBJECTIVES

To discover the incidence and characteristics of EGFR mutations in non-small cell lung cancer (NSCLC) in a single, large cohort as a part of routine diagnostic investigations.

METHODS

We reviewed EGFR mutations investigated by Amplification Refractory Mutation System (ARMS) PCR (covering 29 known mutations) using DNA samples from FFPE tissue or cell clot specimens in a total of 3894 cases of NSCLC analysed between 2012-2014.

RESULTS

EGFR mutations are preferentially associated with adenocarcinomaand adenosquamous histology, particularly those well to moderately differentiated, and were significantly more common in female than male patients irrespective of histological subtypes. Exon 19 deletion (45.7%) and exon 21 L858R (45.6%) accounted for the vast majority of the EGFR mutations detected, with the remaining mutations being infrequent (<2%). Compound mutations were seen in 51 (3%) of the mutant cases, the combination of these compound mutations could be classified into three subgroups according to the potential impact of individual mutations on EGFR TKI therapy. Accordingly, 7 cases had both sensitive mutations, 4 cases harboured one sensitive and one less responsive /uncertain mutation, 19 cases contained one sensitive and one resistant change, and a further 21 cases had two less responsive /uncertain mutations.

CONCLUSION

Our data represents the largest EGFR mutation survey based on routine clinical diagnostic laboratory data from a single institution, it confirms the incidence and characteristics of EGFR mutations in NSCLC seen in Asian patients, and also unravels the combinatorial nature of rare compound EGFR mutations.

Influence of Body Mass Index on the Prognostic Value of Tumor ¹⁸F-FDG Uptake in Stage I Non-Small Cell Lung Cancer

Background

The impact of host energy balance status on outcome of lung cancer has not been fully explored. It is also unknown if there is a potential modifying effect of body mass index (BMI) on tumor cell behavior in patients with early-stage non-small cell lung cancer (NSCLC). We therefore investigated the interactive effects of tumor [¹⁸F]-fluorodeoxyglucose (FDG) avidity and BMI.

Methods

We investigated 1,197 patients with stage I NSCLC who underwent preoperative FDG positron emission tomography followed by curative resection. The primary outcome measure was disease-free survival (DFS). A multivariable Cox proportional hazards model was used to assess the potential independent effects of the prognostic variables. A stratified Cox regression analysis was also performed to assess the potential modifying effects of BMI on the relationship between tumor FDG uptake and patient survival.

Results

There were 145 tumor recurrences and 19 deaths during a median follow-up of 30 months. Tumor-related variables, including tumor size, maximum standardized uptake value (SUVmax), histologic cell type, differentiation, lymphovascular invasion, and visceral pleural invasion, did not differ significantly according to BMI status. In multivariable Cox regression analysis, overweight or obesity [hazard ratio (HR), 0.59; 95% CI, 0.43–0.81; P = 0.001] and tumor SUVmax (HR, 1.72; 95% CI, 1.43–2.07; P < 0.001) were significantly associated with DFS. There was a significant modifying effect of BMI (P for interaction < 0.001 in multivariable analysis). High tumor SUVmax was more strongly associated with worse DFS in normal weight patients (HR, 4.72; 95% CI, 2.77–8.06; P < 0.001) than in overweight or obese patients (HR, 2.61; 95% CI, 1.58–4.31; P < 0.001).

Conclusions

Tumor FDG avidity is an independent predictor of DFS in patients with early-stage NSCLC and this prognostic value was strengthened in normal weight patients than in overweight or obese patients. These results suggest that the host-tumor interaction between host energy balance status and tumor glucose metabolism plays an important role in the outcome of early-stage NSCLC.

Mitochondrial D310 instability in Chinese lung cancer patients

To characterize the somatic mutation spectrum of mitochondrial DNA at D310 in Chinese lung cancer patients and evaluate its potential significance in Chinese lung cancer diagnosis, in this study, 237 samples, including lung tumor, adjacent normal tissue and blood samples of 79 lung cancer patients were analyzed. By comparing sequences of D310 between lung cancer tissues, adjacent normal tissue and blood samples, the somatic mutations at D310 were detected in 17.72% (14/79) of Chinese lung cancer patients; this implied that somatic mutations at D310 could be served as valuable biomarker for diagnostic of Chinese lung cancer. Further analyses indicated that deletion and heterogeneity were the predominant characters for somatic mutations detected at D310 of Chinese lung cancer patients.

[Obesity and lung cancer: incidence and repercussions on epidemiology, pathology and treatments]

INTRODUCTION

Obesity and lung cancer are major public health problems. The purpose of this work is to review the data concerning this association.

METHOD

We report clinical and epidemiological data on obesity and discuss the impact on the incidence of lung cancer, as well as the safety and efficiency of anti-tumor treatments.

RESULTS

Obesity does not contribute to the occurrence of lung cancer, unlike other malignancies. Patients may be more likely to undergo treatment at lower risk. Regarding surgery, obesity makes anaesthesia more difficult, increases the operative duration but does not increase postoperative morbidity and mortality. Chemotherapy and radiotherapy seem to be administered according to the same criteria as patients with normal weight. Paradoxically, survival rates of lung cancer are better in obese patients as well after surgery than after non-surgical treatment.

CONCLUSION

Obesity is related to many neoplasms but not to lung cancer. Regarding long-term survival all treatments combined, it has a favorable effect: this is the "obesity paradox".

Integrative genomic analysis reveals a high frequency of LKB1 genetic alteration in Chinese lung adenocarcinomas

Liver kinase B1 (LKB1) genetic alteration in lung cancer involves not only point mutations and small deletion of several base pairs but also exonic loss. However, most of recent studies in LKB1 gene status only focus on point mutations and small deletion, and thus may underestimate the actual frequency of LKB1 genetic alteration in lung cancer. Thus, an integrative analysis of LKB1 genetic alteration is timely and important for providing a better estimate for the incidence of genetic alterations in this important tumor suppressor gene. One hundred and seven lung adenocarcinomas with more than 70% tumor have been analyzed for mutation of LKB1 as well as LKB1 large deletions detection by using multiplex ligation-dependent probe amplification analysis. These samples were also analyzed for EGFR, KRAS, HER2, BRAF, ALK, ROS1, and RET status in stepwise method. Among 107 lung adenocarcinomas analyzed, 29 (27.1%) harbored LKB1 genetic alteration. Twenty-three (21.5%) harbored LKB1 large exonic deletions and eight (7.48%) had LKB1 points mutations, two samples harbored both LKB1 large exonic deletions and point mutations. Eighty-seven samples (81.31%) harbored known driver mutations and 20 samples (18.69%) had no identifiable driver mutations. A high rate of LKB1 genetic alteration in Chinese lung adenocarcinomas is revealed by the integrative analysis of point mutation and exonic deletion. Moreover, LKB1 genetic alterations are concurrent with EGFR, KRAS, HER2, and CD74-ROS fusions.

Body mass index and its association with clinical outcomes for advanced non-small-cell lung cancer patients enrolled on Eastern Cooperative Oncology Group clinical trials

INTRODUCTION

Obesity increases the risk of death from many adverse health outcomes and has also been linked with cancer outcomes. The impact of obesity on outcomes of advanced non-small-cell lung cancer patients is unclear.

METHODS

The authors evaluated the association of body mass index (BMI) and outcomes in 2585 eligible patients enrolled in three consecutive first-line trials conducted by the Eastern Cooperative Oncology Group. BMI was categorized as underweight (BMI < 18.5 kg/m), normal weight (BMI: 18.5 to < 25 kg/m), overweight (BMI: 25 to < 30 kg/m), and obese (BMI ≥ 30 kg/m). In addition to analyzing overall and progression-free survival, reasons for treatment discontinuation were also assessed by BMI group.

RESULTS

Of the patients enrolled, 4.6% were underweight, 44.1% were normal weight, 34.3% of patients were classified as overweight, and 16.9% were obese. Nonproportional hazards existed for obese patients relative to the other three groups of patients, with a change in overall survival hazard occurring at approximately 16 months. In multivariable Cox models, obese patients had superior outcomes earlier on study compared with normal/overweight patients 0.86 (HR=0.86, p=0.04; 95% CI: 0.75-0.99), but later experienced increased hazard (HR=1.54, p< 0.001; 95% CI: 1.22-1.94), indicating a time effect while undergoing treatment.

CONCLUSION

Data from these three trials suggest differential outcomes associated with BMI, and additional studies of the mechanisms underlying this observation, as well as dietary and lifestyle interventions, are warranted to help optimize therapy.

Particulate air pollution and mortality in a cohort of Chinese men

Few prior cohort studies exist in developing countries examining the association of ambient particulate matter (PM) with mortality. We examined the association of particulate air pollution with mortality in a prospective cohort study of 71,431 middle-aged Chinese men. Baseline data were obtained during 1990-1991. The follow-up evaluation was completed in January, 2006. Annual average PM exposure between 1990 and 2005, including TSP and PM10, were estimated by linking fixed-site monitoring data with residential communities. We found significant associations between PM10 and mortality from cardiopulmonary diseases; each 10 μg/m(3) PM10 was associated with a 1.6% (95%CI: 0.7%, 2.6%), 1.8% (95%CI: 0.8%, 2.9%) and 1.7% (95%CI: 0.3%, 3.2%) increased risk of total, cardiovascular and respiratory mortality, respectively. For TSP, we observed significant associations only for cardiovascular morality. These data contribute to the scientific literature on long-term effects of particulate air pollution for high exposure settings typical in developing countries.

Outcome of active anti-cancer treatment in elderly patients with advanced non-small cell lung cancer: A single center experience

BACKGROUND

This study aimed to evaluate the characteristics of active anti-cancer treatment (AAT) compared with best supportive care (BSC) in elderly patients with advanced non-small cell lung cancer (NSCLC).

METHODS

A retrospective analysis of 144 patients, aged 70 or older, with stage IIIb/IV NSCLC from 672 patients with confirmed lung cancer, was conducted.

RESULTS

Median age at diagnosis was 77 years and median survival time was five months. On multivariate analysis, AAT independently contributed to a decreased hazard ratio of death (P = 0.04), whereas male gender (P = 0.004), a body mass index of less than 18.5 (P = 0.004), and a poor performance score were associated with an increased risk of death (P < 0.001). The 52 subjects receiving AAT experienced longer survival than the 92 subjects receiving BSC (median seven months [AAT] versus three months [BSC]; P < 0.001). When sub-classified into five-year age intervals, AAT was a significant advantage in overall survival (OS) to patients aged 70-74, but not to those ≥75 years old.

CONCLUSIONS

AAT for patients ≥70 years old with advanced NSCLC extended OS. However, care should be taken in decisions on active anti-cancer treatments for patients over 75 years old. A prospective multicenter trial is required in the near future.

Body mass index, lifetime smoking intensity and lung cancer risk

There is as yet no generally accepted explanation for the common finding that low body mass index (BMI) is associated with an increased risk of lung cancer. We investigated this association in a Canadian population-based case-control study (1996-2002) with a particular view to assessing the hypothesis that the observed association was due to residual confounding by smoking. Analyses were based on 1,076 cases and 1,439 controls who provided their height at enrollment and their weight at two points in time, at age 20 and 2 years before enrollment. BMI, in kg/m(2) , was classified into underweight (<18.5), normal (18.5-24.9), overweight (25.0-29.9), and obese (≥30). Smoking history was synthesized into a comprehensive smoking index (CSI) that integrated duration, intensity and time since quitting. Odds ratios (ORs) and 95% confidence intervals (CIs) for BMI-lung cancer associations were estimated, adjusting for CSI as well as several sociodemographic, lifestyle and occupational factors. The normal BMI category was used as the reference. Among those who were underweight at age 20, there was a lower risk of lung cancer (OR = 0.69, 95% CI: 0.50-0.95). Conversely, lung cancer risk was increased among those who were underweight 2 years before enrollment (OR = 2.30, 95% CI: 1.30-4.10). The results were almost identical when stratifying analyses based on smoking history into never/lighter and heavier smokers. The inverse association between recent BMI and lung cancer is unlikely to be largely attributable to residual confounding by smoking. Reverse causality or a true relationship between BMI and lung cancer remain plausible.

Descriptive data on cancerous lung lesions detected by auto-fluorescence bronchoscope: A five-year study

BACKGROUND:

Auto-fluorescence bronchoscopy (AFB) has been used for the identification and localization of intra-epithelial pre-neoplastic and neoplastic lesions within the bronchus.

OBJECTIVES:

To determine the applicability of AFB for the detection and localization of precancerous and cancerous lesions, in addition to analyzing the morphologic presentation, their association to histological type and the variation between genders.

METHODS:

A five-year study involving 4983 patients, who underwent routine bronchoscopy [B] examination in a local tertiary teaching hospital, was done. The B examination was performed under intratracheal lidocaine, and samples were obtained using suitable approach. One thousand four hundred and eighty-five pathologically confirmed lung cancer patients were included in the study. The following parameters were studied: Morphological presentation, biopsy sites, histology. Differences between the groups were analyzed using Chi square test.

RESULT:

One thousand four hundred and eighty-five patients who had hyperplasia or neoplastic lesions were further confirmed as lung cancer pathologically. Lung cancer was more commonly found in the right lung (51.58% vs. 42.82%). The lesion occurred more frequently in the upper lobe than the lower lobe (44.17% vs. 22.42%). Male patients with squamous cell carcinoma showed upper lobe involvement more commonly, while the left main bronchus was more commonly involved in female patients. Adenocarcinoma mostly involved lesion of the upper lobe. Squamous cell carcinoma and small cell carcinoma were the major proliferative types (80.15% and 76.16% respectively).

CONCLUSION:

AFB is efficient in the detection of pre-invasive and invasive lung lesions. The morphological presentation is associated to the histological type. There is variation in the presentation and histology of cancerous lung lesions between genders.

Identification of sequence polymorphisms in the D-loop region of mitochondrial DNA as a risk factor for lung cancer

Accumulation of single nucleotide polymorphisms (SNPs) in the displacement loop (D-loop) of mitochondrial DNA (mtDNA) may be associated with an increased cancer risk. We investigated the lung cancer risk profile of D-loop SNPs in a case-controlled study. The minor alleles of nucleotides 235A/G and 324A/G were associated with an increased risk for lung cancer patients. The minor alleles of the nucleotides 151C/T, 200A/G, 524C/CA, and 16274G/A were specifically associated with the cancer risk of squamous cell carcinoma, whereas the minor allele of nucleotide 16298T/C was specifically associated with the risk of small cell lung cancer. In conclusion, SNPs in mtDNA are potential modifiers of lung cancer risk. The analysis of genetic polymorphisms in the mitochondrial D-loop can help identify subgroups of patients who are at a high risk of developing lung cancer.

The importance of exposure rate on odds ratios by cigarette smoking and alcohol consumption for esophageal adenocarcinoma and squamous cell carcinoma in the Barrett's Esophagus and Esophageal Adenocarcinoma Consortium

BACKGROUND

Cigarette smoking is associated with esophageal adenocarcinoma (EAC), esophagogastric junctional adenocarcinoma (EGJA) and esophageal squamous cell carcinoma (ESCC), and alcohol consumption with ESCC. However, no analyses have examined how delivery rate modifies the strength of odds ratio (OR) trends with total exposure, i.e., the impact on the OR for a fixed total exposure of high exposure rate for short duration compared with low exposure rate for long duration.

METHODS

The authors pooled data from 12 case-control studies from the Barrett's Esophagus and Esophageal Adenocarcinoma Consortium (BEACON), including 1242 (EAC), 1263 (EGJA) and 954 (ESCC) cases and 7053 controls, modeled joint ORs for cumulative exposure and exposure rate for cigarette smoking and alcohol consumption, and evaluated effect modification by sex, body mass index (BMI), age and self-reported acid reflux.

RESULTS

For smoking, all sites exhibited inverse delivery rate effects, whereby ORs with pack-years increased, but trends weakened with increasing cigarettes/day. None of the examined factors modified associations, except for ESCC where younger ages at diagnosis enhanced smoking effects (P<0.01). For EAC and EGJA, ORs with drink-years exhibited inverse associations in <5 drinks/day consumers and no association in heavier consumers. For ESCC, ORs with drink-years increased, with trends strengthening with greater drinks/day. There was no significant effect modification, except for EAC and EGJA where acid reflux mitigated the inverse associations (P=0.02). For ESCC, younger ages at diagnosis enhanced drinking-related ORs (P<0.01).

CONCLUSIONS

Patterns of ORs by pack-years and drink-years, delivery rate effects and effect modifiers revealed common as well as distinct etiologic elements for these diseases.

A risk model for lung cancer incidence

Risk models for lung cancer incidence would be useful for prioritizing individuals for screening and participation in clinical trials of chemoprevention. We present a risk model for lung cancer built using prospective cohort data from a general population which predicts individual incidence in a given time period. We build separate risk models for current and former smokers using 169,035 ever smokers from the multicenter European Prospective Investigation into Cancer and Nutrition (EPIC) and considered a model for never smokers. The data set was split into independent training and test sets. Lung cancer incidence was modeled using survival analysis, stratifying by age started smoking, and for former smokers, also smoking duration. Other risk factors considered were smoking intensity, 10 occupational/environmental exposures previously implicated with lung cancer, and single-nucleotide polymorphisms at two loci identified by genome-wide association studies of lung cancer. Individual risk in the test set was measured by the predicted probability of lung cancer incidence in the year preceding last follow-up time, predictive accuracy was measured by the area under the receiver operator characteristic curve (AUC). Using smoking information alone gave good predictive accuracy: the AUC and 95% confidence interval in ever smokers was 0.843 (0.810-0.875), the Bach model applied to the same data gave an AUC of 0.775 (0.737-0.813). Other risk factors had negligible effect on the AUC, including never smokers for whom prediction was poor. Our model is generalizable and straightforward to implement. Its accuracy can be attributed to its modeling of lifetime exposure to smoking.

Body mass index and risk of lung cancer among never, former, and current smokers

BACKGROUND

Although obesity has been directly linked to the development of many cancers, many epidemiological studies have found that body mass index (BMI)--a surrogate marker of obesity--is inversely associated with the risk of lung cancer. These studies are difficult to interpret because of potential confounding by cigarette smoking, a major risk factor for lung cancer that is associated with lower BMI.

METHODS

We prospectively examined the association between BMI and the risk of lung cancer among 448 732 men and women aged 50-71 years who were recruited during 1995-1996 for the National Institutes of Health-AARP Diet and Health Study. BMI was calculated based on the participant's self-reported height and weight on the baseline questionnaire. We identified 9437 incident lung carcinomas (including 415 in never smokers) during a mean follow-up of 9.7 years through 2006. Multivariable Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) with adjustment for lung cancer risk factors, including smoking status. To address potential bias due to preexisting undiagnosed disease, we excluded potentially unhealthy participants in sensitivity analyses. All statistical tests were two-sided.

RESULTS

The crude incidence rate of lung cancer over the study follow-up period was 233 per 100 000 person-years among men and 192 per 100 000 person-years among women. BMI was inversely associated with the risk of lung cancer among both men and women (BMI ≥35 vs 22.5-24.99 kg/m(2): HR = 0.81, 95% CI = 0.70 to 0.94 and HR = 0.73, 95% CI = 0.61 to 0.87, respectively). The inverse association was restricted to current and former smokers and was stronger after adjustment for smoking. Among smokers, the inverse association persisted even after finely stratifying on smoking status, time since quitting smoking, and number of cigarettes smoked per day. Sensitivity analyses did not support the possibility that the inverse association was due to prevalent undiagnosed disease.

CONCLUSIONS

Our results suggest that a higher BMI is associated with a reduced risk of lung cancer in current and former smokers. Our inability to attribute the inverse association between BMI and the risk of lung cancer to residual confounding by smoking or to bias suggests the need for considering other explanations.

Sequence polymorphisms of the mitochondrial displacement loop and outcome of non-small cell lung cancer

Accumulation of single-nucleotide polymorphisms (SNPs) in the displacement loop (D-loop) of mitochondrial DNA (mtDNA) may be associated with disease outcome. Our team investigated the prediction power of D-loop SNPs in non-small cell lung cancer (NSCLC) outcome. In an overall multivariate analysis, allele 16390 was identified as an independent predictor for NSCLC outcome. The length of survival of patients with allele 16390A was significantly shorter than that of patients with allele 16390G (relative risk, 0.323; 95% CI, 0.109-0.951; p=0.040). The analysis of genetic polymorphisms in the mitochondrial D-loop can help identify NSCLC patient subgroups at a high risk for a poor disease outcome.

Lung cancer: epidemiology, etiology, and prevention

Lung cancer is the leading cause of cancer death in the United States and around the world. A vast majority of lung cancer deaths are attributable to cigarette smoking, and curbing the rates of cigarette smoking is imperative. Understanding the epidemiology and causal factors of lung cancer can provide additional foundation for disease prevention. This article focuses on modifiable risk factors, including tobacco smoking, occupational carcinogens, diet, and ionizing radiation. It also discusses briefly the molecular and genetic aspects of lung carcinogenesis.

Lung cancer: epidemiology, etiology, and prevention

Lung cancer is the leading cause of cancer death in the United States and around the world. A vast majority of lung cancer deaths are attributable to cigarette smoking, and curbing the rates of cigarette smoking is imperative. Understanding the epidemiology and causal factors of lung cancer can provide additional foundation for disease prevention. This article focuses on modifiable risk factors, including tobacco smoking, occupational carcinogens, diet, and ionizing radiation. It also discusses briefly the molecular and genetic aspects of lung carcinogenesis.

Obesity and weight loss at presentation of lung cancer are associated with opposite effects on survival

BACKGROUND

Lung cancer is the second most common neoplasm and the leading cause of cancer deaths in the United States. In cancer, weight loss and obesity are associated with reduced survival. However, the effect of obesity or weight loss at presentation on lung cancer survival has not been well studied.

MATERIALS AND METHODS

Using an extensive cancer dataset, we identified 76,086 patients diagnosed with lung cancer during the period of 1998-2002, of which 14,751 patients presented with obesity and/or weight loss. We examined the relationship between survival and weight loss or obesity at diagnosis using univariate and multivariate analysis.

RESULTS

Median survival time (MST) for all lung cancer patients was 8.7 mo. Patients presenting with weight loss (15.8%) had shorter MST versus those who did not (6.4 versus 9.2 mo, P < 0.001) and patients with weight loss had significantly shortened MST for all stages and histologic subtypes. In contrast, obese patients at presentation (5.4%) had longer MST relative to non-obese patients (13.0 versus 8.6 mo, P < 0.001), which was significant across all stages and histologic subtypes. Multivariate analysis revealed that the absence of weight loss was an independent, positive predictor of improved survival (HR = 0.087, P < 0.001), while the absence of obesity was an independent predictor of worsened survival in lung cancer (HR = 1.16, P < 0.001).

CONCLUSIONS

Our results demonstrate an inverse relationship between survival and weight loss at presentation and a potentially protective effect of obesity in lung cancer survival, which could be due to greater physiologic reserves, thereby prolonging life by slowing the progress of cancer cachexia.

[Advances in early diagnosis of lung cancer]

Lung cancer is the most common cause of cancer death worldwide. Early diagnosis and early treatment are of great importance. Chest X-ray, spinal CT, bronchoscopy and sputum cytology have long been used as screening or diagnostic modalities for early detection of lung cancer. However, these methods have limitations in sensitivity, specificity or utility in some degree. In recent years, researchers all over the world have done lots of work on finding and identifying biomarkers for the early diagnosis of lung cancer. In this paper, recent developments in this field are reviewed.

Forced expiratory volume in one second as a prognostic factor in advanced non-small cell lung cancer

INTRODUCTION

Reduced lung function is an important risk factor for lung cancer and increases surgical risk in patients with operable stages of lung cancer. Nevertheless, there have been few studies to reveal association of lung function with mortality in patients with advanced lung cancer. The aim of this study was to investigate whether low forced expiratory volume in 1 second (FEV1) is an independent predictor of mortality in patients with advanced lung cancer.

METHODS

Data were retrospectively collected from patients with non-small cell lung cancer of stage IIIB or IV and available spirometry at diagnosis of lung cancer. They had the last follow-up consecutively between April 2003 and July 2009 in a tertiary referral hospital.

RESULTS

Among a total of 156 patients, 118 died as of July 2009. Their mean age was 65 years; 115 (74%) were men. Mean FEV1 was 1.91 liters (79% of predicted). Seventy-one patients (46%) had adenocarcinoma, and 48 (31%) had squamous cell carcinoma. In a multivariate analysis using Cox regression model, independent prognostic factors were FEV1 less than 50% of predicted (hazard ratio [HR] = 2.704, 95% confidence interval [CI]: 1.516-4.823, p = 0.001), chemotherapy (HR = 0.311, 95% CI: 0.192-0.503, p < 0.001), adenocarcinoma (HR = 0.459, 95% CI: 0.300-0.701, p < 0.001), body mass index (HR = 0.921, 95% CI: 0.870-0.975, p = 0.005), and the presence of malignant pleural effusion (HR = 1.673, 95% CI: 1.102-2.540, p = 0.016).

CONCLUSIONS

Reduced FEV1 is strongly associated with mortality in advanced non-small cell lung cancer.

Nicotine dependence and quitting behaviors among menthol and non-menthol smokers with similar consumptive patterns

AIMS

This study examines the associations between usual cigarette brand (i.e. menthol, non-menthol) and markers for nicotine dependence and quitting behaviors.

DESIGN

The 2003 and 2006/07 Tobacco Use Supplements to the Current Population Surveys were pooled to conduct secondary data analysis.

SETTING

National data were collected using in-person and telephone computer-assisted interviews by the United States Census Bureau among civilian, non-institutionalized people aged 15 years and older.

PARTICIPANTS

Data were analyzed among daily current smokers aged 18+ (n = 46,273).

MEASUREMENTS

The associations between usual cigarette brand and time to first cigarette within 5 and 30 minutes after waking, quit attempts in the past 12 months and length of smoking abstinence in the past 12 months were examined. Bivariate and multivariate logistic regression models were stratified by smoking intensity: ≤5, 6-10, 11-19 and 20+ cigarettes per day.

FINDINGS

Menthol smokers reported a mean of 13.05 compared with 15.01 cigarettes per day among non-menthol smokers (P < 0.001). Multivariate results showed that among smokers consuming 6-10 cigarettes per day, menthol smokers were significantly more likely than non-menthol smokers to consume their first cigarette within 5 minutes after waking (odds ratio = 1.22, 95% confidence interval = 1.05,1.43). The multivariate models did not show significant associations between usual cigarette brand and quit attempts in past 12 months or duration of smoking abstinence >2 weeks in the past 12 months.

CONCLUSIONS

Findings from this national survey of daily smokers demonstrate that menthol smokers in the United States who report consuming 6-10 cigarettes per day show greater signs of nicotine dependence than comparable non-menthol smokers.

Spectrum of LKB1, EGFR, and KRAS mutations in chinese lung adenocarcinomas

INTRODUCTION

Somatic LKB1 mutations are found in lung adenocarcinomas at different frequencies in Caucasian and East Asian (Japanese and Korean) populations. This study was designed to characterize the frequency of LKB1 mutations, their relationship to EGFR and KRAS mutations, and their associated clinicopathologic characteristics in Chinese patients.

METHODS

Two hundred thirty-nine lung adenocarcinomas consecutively collected from October 2007 to July 2009 were dissected into 3 to 4 small (3 mm) pieces for histopathological analyses of tumor content. Genomic DNA and/or cDNA from 86 samples with more than 70% tumor content were used for sequencing of LKB1 (exons 1-9), EGFR (exons 18-21), and KRAS (exon 2). LKB1 germline mutation status was determined by sequencing of genomic DNA from matched histologically distant lung tissues that are histologically normal.

RESULTS

6.9% of lung adenocarcinomas harbored LKB1 somatic mutations. A total of 10.5% of patients had an LKB1 germline polymorphism, F354L. Interestingly, in two of these patients, tumors displayed loss of heterozygosity at this allele. EGFR kinase domain and KRAS mutations were found in 66.3% and 2.3% of Chinese lung adenocarcinomas, respectively. Concurrent LKB1 and EGFR somatic mutations were observed in one patient. Both KRAS-mutant tumors harbored LKB1 mutations.

CONCLUSIONS

These data provide important clinical and molecular characteristics of lung adenocarcinomas from Chinese patients.

Body-mass index and cancer mortality in the Asia-Pacific Cohort Studies Collaboration: pooled analyses of 424,519 participants

BACKGROUND

Excess bodyweight is an established risk factor for several types of cancer, but there are sparse data from Asian populations, where the proportion of overweight and obese individuals is increasing rapidly and adiposity can be substantially greater for the same body-mass index (BMI) compared with people from Western populations.

METHODS

We examined associations of adult BMI with cancer mortality (overall and for 20 cancer sites) in geographic populations from Asia and from Australia and New Zealand (ANZ), within the Asia-Pacific Cohort Studies Collaboration, by use of Cox regression analysis. Pooled data from 39 cohorts (recruitment 1961-99, median follow-up 4 years) were analysed for 424,519 participants (77% Asian; 41% female; mean recruitment age 48 years) with individual data on BMI.

FINDINGS

After excluding those with follow-up of less than 3 years, 4872 cancer deaths occurred in 401,215 participants. Hazard ratios for cancer sites with increased mortality risk in obese (BMI > or = 30 kg/m(2)) compared with normal weight participants (BMI 18.5-24.9 kg/m(2)) were: 1.21 (95% CI 1.09-1.36) for all-cause cancer (excluding lung and upper aerodigestive tract), 1.50 (1.13-1.99) for colon, 1.68 (1.06-2.67) for rectum, 1.63 (1.13-2.35) for breast in women 60 years or older, 2.62 (1.57-4.37) for ovary, 4.21 (1.89-9.39) for cervix, 1.45 (0.97-2.19) for prostate, and 1.66 (1.03-2.68) for leukaemia (all after left censoring at 3 years). The increased risk associated with a 5-unit increase in BMI for those with BMI of 18.5 kg/m(2) or higher was 1.09 (95% CI 1.04-1.14) for all cancers (excluding lung and upper aerodigestive tract). There was little evidence of regional differences in relative risk of cancer with higher BMI, apart from cancers of the oropharynx and larynx, where the association was inverse in ANZ and absent in Asia.

INTERPRETATION

Overweight and obese individuals in populations across the Asia-Pacific region have a significantly increased risk of mortality from cancer. Strategies to prevent individuals from becoming overweight and obese in Asia are needed to reduce the burden of cancer that is expected if the obesity epidemic continues.

FUNDING

National Health and Medical Research Council of Australia, Health Research Council of New Zealand, and Pfizer Inc.

Body mass index and smoking-related lung cancer risk in the Singapore Chinese Health Study

BACKGROUND

Smokers with low body mass index (BMI) may be more susceptible to lung cancer.

METHODS

We prospectively examined the association between baseline BMI and lung cancer risk in the Singapore Chinese Health Study, a cohort of 63 257 Chinese enrolled between 1993 and 1998.

RESULTS

After adjustment for smoking intensity and duration, BMI was inversely associated with risk of lung cancer among current smokers (P for trend=0.0004). Current smokers at different dosage of smoking with low BMI had significantly higher risk for lung cancer than those with high BMI. Hazard ratios (95% confidence intervals) of lung cancer for heavy smokers with BMI of > or =28, 24-<28, 20-<24, and <20 kg m(-2) were 6.37 (2.10-19.30), 9.01 (5.04-16.10), 8.53 (6.35-11.5), and 11.12 (6.60-18.70), respectively, as compared with nonsmokers. BMI had no modifying effects on lung cancer risk among nonsmokers and former smokers.

CONCLUSION

Smokers with lower BMI may experience an enhanced risk of lung cancer. The findings have significant public-health implication given the increase in smoking prevalence in developing countries, where people still have relatively low BMI.

Detection of lung cancer by oral examination

Lung cancer continues to be the leading cause of cancer deaths worldwide. Cigarette smoking is the predominant cause of lung cancer. Researchers found that tobacco-induced molecular changes in the oral epithelium are similar to those in the lung epithelium. Furthermore, there has been considerable progress in investigating the tumorigenesis of oral epithelium using molecular markers. These results offer hope that we can predict lung cancer in smokers by oral examination, which is much easier and more practical than lung biopsy. The hypothesis is to collect oral epithelial cells by gently scraping the oral mucosa, and analyze the DNA variation in these cells using molecular biological methods. Therefore, the oral epithelium is serving as a surrogate tissue for assessing smoking-induced molecular damage to the lungs and thus have important implications for early detection of lung cancer.