Secondhand Smoking and the Risk of Esophageal Squamous Cell Carcinoma in a High Incidence Region, Kashmir, India: A Case-control-observational Study

Environmental tobacco smoking (ETS) and esophageal cancer: A population-based case-control study in Jiangsu Province, China

Esophageal cancer continues to pose a significant public health issue in areas with increased incidence rates such as China. Although involuntary smoking was defined as a group 1 carcinogen for lung cancer, few studies have explored the impact of environmental tobacco smoking (ETS) on esophageal cancer. In this paper, we examined the association between ETS and esophageal cancer in high-risk groups in Jiangsu Province, China. Epidemiologic data were collected for 2969 newly diagnosed cases and 8019 population controls including exposure to active/passive smoking and risk factors. The unconditional logistic regression model and the semi-Bayes (SB) method were applied to assess adjusted odds ratios (ORs) and confidence intervals (CIs). ETS exposure (ever vs. never) was positively associated with esophageal cancer with an SB-adjusted OR (95% CI) of 1.44 (1.31-1.58) among overall population, and 1.56 (1.35-1.82) among non-smokers (i.e., non-active smokers), with corresponding population attributable fractions of 15.0% (95% CI: 10.3%-18.9%) and 12.1% (95% CI: 8.8%-19.8%), respectively. The association was more prominent in men at work and in women at home, with SB-adjusted OR (95% CI) of 1.36 (1.17-1.58) and 1.61 (1.35-1.58), respectively. A dose-response relationship between ETS exposure and the disease was detected across the entire population as well as in non-smokers. This is the largest population-based case-control study of ETS and esophageal cancer and the first study to evaluate such association among non-smokers in a Chinese population. We recommend strengthening the ongoing anti-tobacco public health initiatives in China with a particular emphasis on creating a tobacco-free work/home environment.

Secondhand smoke is associated with peptic ulcer disease and gastroesophageal reflux disease in non-smokers in a large Taiwanese population study

Background

Active smokers are known to be at an increased risk of both gastroesophageal reflux disease (GERD) and peptic ulcer disease (PUD), however the role of passive smoking remains unclear. In this study, we aimed to examine whether secondhand smoke (SHS) is associated with PUD and GERD.

Methods

In this population-based study, we conducted a large-scale analysis with 88,297 never-smokers (male: 18,595; female: 69,702; mean age 50.1 ± 11.0 years) from the Taiwan Biobank. The exposure group was comprised of those who had been exposed to SHS, and the no exposure group as those without SHS exposure. According to the frequency of exposure, we further divided the participants into "no exposure," "<1 h per week," and "≥1 h per week" groups. A cutoff point of 1 h per week was chosen according to the median exposure time in our participants. Associations between SHS and SHS frequency with PUD and GERD were assessed.

Results

Of the 88,297 enrolled participants, 11,909 (13.5%) had PUD and 76,388 (86.5%) did not. In addition, 11,758 (13.3%) had GERD and 76,539 (86.7%) did not. Multivariable analysis showed a significant association between SHS with PUD (odds ratio [OR] = 1.166; 95% confidence interval [CI] = 1.084-1.254; p < 0.001), and GERD (OR = 1.131; 95% CI = 1.053-1.216; p = 0.001). Furthermore, those exposed to SHS ≥ 1 h per week (vs. no exposure) were associated with higher risks of PUD (OR = 1.232; 95% CI = 1.121-1.355; p < 0.001) and GERD (OR = 1.200; 95% CI = 1.093-1.319; p < 0.001).

Conclusion

SHS was significantly associated with PUD and GERD. Furthermore, exposure to SHS ≥ 1 h per week (vs. no exposure) was associated with a 1.23-fold higher risk of PUD and 1.20-fold higher risk of GERD. This study represents the largest population-based investigation to explore the association between SHS with PUD and GERD in Taiwanese never-smokers.

Colorectal Cancer (CRC): Investigating the Expression of the Suppressor of Fused (SuFu) Gene and Its Relationship with Several Inflammatory Blood-Based Biomarkers

BACKGROUND

Suppressor of fused (SuFu) is a tumor-suppressor gene that regulates hedgehog signaling. Its involvement in some malignancies is broadly accepted. However, its association with colorectal cancer (CRC) pathogenesis is not clear. Likewise, no study has clearly associated blood-based inflammatory biomarkers with cancer diagnosis/prognosis as yet.

AIM

Our goal was to look at SuFu expression levels in CRC patients and its relationship with other clinicopathological factors. Additionally, we looked into the function of a few blood-based biomarkers in CRC and whether or not a combined strategy at the genetic and clinical levels can be applied in CRC.

METHODS

The investigation included 98 histopathologically confirmed CRC samples and adjacent normal tissues (controls). A colonoscopy was followed by a targeted biopsy for each suspected colon cancer patient. A CT scan and MRI were also performed on every patient with rectal cancer. Real-time polymerase chain reaction and immunohistochemistry (IHC) were used for assessment. A Beckman Coulter DxH900 was used to examine blood parameters. A Beckman Coulter DxI800 was used to identify pretreatment carcinoma embryonic antigens (CEA) and carbohydrate antigens (CA 19-9) in CRC patients.

RESULTS

The expression of SuFu was associated with gender, education, passive smoking, tumor grade, perineural invasion (PNI), lymph node metastasis (LNM), node status, stage, vital status, and recurrence (p < 0.05). In the combined analysis, the areas under the curve produced by the platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), and red cell distribution width (RDW) were the greatest (AUCRDW+PLR+NLR = 0.91, 95% CI: 0.86-0.93, p < 0.05). Furthermore, the most severe pathological features were linked to RDW, PLR, NLR, and HPR. SuFu expression, node status, LNM, PNI, and stage all had significant correlations with OS and DFS rates in IHC-based univariate survival analysis (p < 0.05). According to the Cox regression, CA-19.9 had a strong independent predictive link with 3-year DFS (p < 0.05).

CONCLUSION

In CRC, SuFu was downregulated both transcriptionally and translationally, was primarily nucleo-cytoplasmic, and was expressed less in high-grade tumors. In addition, SuFu was linked to a poor overall and disease-free survival rate. It may be possible to use SuFu as a therapeutic target for CRC in the future. However, SuFu expression had no effect on RDW, PLR, NLR, or HPR serum levels.

Epidemiological Review: Esophagus Squamous Cell Carcinoma in India

Worldwide the incidence of esophagus squamous cell carcinoma (ESCC), remains one of the most common causes of cancer death. ESCC is one of the leading types of cancer in the North and Northeast regions of India among both genders. Risk factors of ESCC include tobacco, alcohol, areca nut, hot beverages, low fruit diet, poor oral hygiene, unpiped water, and human papillomavirus infection. This review tries to elaborate on various modifiable risk factors for ESCC, which have been studied worldwide and need to be studied in India. PubMed was used as a search platform using keywords, such as “esophagus cancer,” “esophagus squamous cell carcinoma,” “epidemiology,” “India,” “incidence,” “mortality,” “risk factors,” “treatment,” “survival,” “prevention” and their corresponding Medical Subject Heading terms, were used in combination with Boolean operators “OR” and “AND.” Studies from India are mostly hospital-based case-control studies from the North region. Further research is required in India to understand the etiology, to design large-scale screening and prevention strategies.

Malondialdehyde Level and Tissue Apoptosis Count as an Early-Detection Marker of Oral Potentially Malignant Disorders

OBJECTIVES

 The malondialdehyde (MDA) level and TA count represent the progression of oral potentially malignant disorders (OPMD) to malignancy and thus may be used as an indicator of oral epithelial dysplasia (OED). This study aimed to determine the MDA level and tissue apoptosis (TA) count in oropharyngeal tissue of Wistar rats exposed to sidestream cigarette smoke.

MATERIALS AND METHODS

 Wistar rats were divided into three groups: T4 group (4-week cigarette smoke exposure), T8 group (8-week cigarette smoke exposure), and control group, which was not exposed to cigarette smoke. The oropharyngeal tissue of the rats from each group was examined histopathologically to count the number of apoptotic cells, and then the blood serum was made to measure the MDA level.

STATISTICAL ANALYSIS

 Bonferroni test was performed to see the differences in each group for MDA level. While the data from tissue apoptosis were analyzed using Mann-Whitney U test for the significance. All data were considered significant if p < 0.05.

RESULTS

 The MDA level and TA count increased as the duration of cigarette smoke exposure increased. In the T8 group, the MDA level and TA count were significantly higher compared with the T4 and control groups with a p-value < 0.05.

CONCLUSIONS

 Exposure to sidestream cigarette smoke increased the TA count and MDA level in the oropharyngeal tissue of Wistar rats. The TA count and MDA level may be used as markers of OPMD.

Potential Impact of Time Trend of Lifestyle Risk Factors on Burden of Major Gastrointestinal Cancers in China

BACKGROUND & AIMS

China has the largest number of incident liver, esophageal, gastric, and colorectal cancer cases in 2020. Examining the time trend of relevant lifestyle risk factors would help project the trend of these gastrointestinal (GI) cancer incidence in China.

METHODS

We estimated the time trend of the lifestyle factors based on the China Health and Nutrition Survey 1991 to 2011. We applied the comparative risk assessment method to estimate the population attributable fraction of GI cancers attributable to each risk factor. We also projected the prevalence of lifestyle factors and the associated burden of GI cancer from 2011 to 2031.

RESULTS

In 2011, 56.5% of colorectal, 59.8% of gastric, 48.5% of esophageal, and 35.2% of liver cancer in China were attributable to the lifestyle risk factors under study. Smoking, sodium intake, low vegetable intake, and low fruit intake have improved over time but remained far from optimal and are expected to be responsible for 170,000, 35,000, 22,000, and 50,000 GI cancer cases in 2031, respectively. High body mass index, red and processed meat consumption, and low physical activity are expected to contribute increasingly more GI cancer, accounting for 142,000, 185,000, 60,000, and 53,000 cases in 2031, respectively. The estimated population attributable fraction for all risk factors in 2031 is 52.1%.

CONCLUSIONS

Lifestyle risk factors have had an impact on the risk of GI cancer in China, and the impact is projected to increase. If everyone could adhere to the optimal lifestyle, half of all GI cancer events would be prevented by year 2031.

Esophageal cancer: the rise of adenocarcinoma over squamous cell carcinoma in the Asian belt

Esophageal cancer is a common cancer worldwide with a high associated mortality rate. Amongst the two most frequent subsets of disease, squamous cell carcinoma (SCC) and adenocarcinoma (AC), there has been an epidemiologic shift towards adenocarcinoma over the last few decades. However, squamous cell carcinoma still predominates worldwide. Within Western countries, obesity has been associated with an increase in esophageal AC. A striking report from the World Health Organization (WHO) stated that worldwide obesity has tripled since 1975. In 2016, the WHO reported that greater than 1.9 billion adults are overweight and over 650 million were obese. In this review our goal is to analyze the esophageal cancer trends of China, which is the largest contributor among the esophageal cancer "Asian belt." Our intent is to evaluate whether there is a correlation between the rise in esophageal adenocarcinoma and obesity in this esophageal cancer "hotspot." With further analysis, the high-risk populations that are identified can be targeted to implement preventative strategies. This focus will aid in decreasing the burden of esophageal cancer at the global health level by addressing preventative strategies, such as screening endoscopy and lifestyle modifications. For example, WHO developed a global action plan on physical activity in response to the rise in obesity worldwide. Prevention is key to decreasing the rate of esophageal adenocarcinoma as majority of cases are diagnosed in the late stages leading to high mortality rates.

Identification of key genes and pathways associated with esophageal squamous cell carcinoma development based on weighted gene correlation network analysis

Background: As one of the most aggressive malignancies, esophageal squamous cell carcinoma(ESCC) remains one of the leading causes of cancer related death worldwide. The majority of ESCCs are diagnosed at advanced stages with poor five-year survival rate, making it urgent to identify specific genes and pathways associated with its initiation and prognosis.

Materials and Methods: The differentially expressed genes in TCGA were analysed to construct a co-expression network by WGCNA. Gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis were performed for the selected genes. Module-clinical trait relationships were analyzed to explore the genes and pathways that associated with clinicopathological parameters of ESCC. Log-rank tests and COX regression were used to identify the prognosis-related genes.

Results: The brown module containing 716 genes which most significantly contributed to ESCC. GO analysis suggested enrichment of adaptive immune response, cyclin-dependent protein serine, regeneration and mRNA metabolic process. KEGG analysis indicated pathways including Cellular senescence, Ribosome biogenesis, Proteasome, Base excision repair and p53 signaling pathway. Clinical stage was associated with cyan module; clinical M was associated with grey60 module; clinical T was associated with darkturquoise module; while clinical N, histological type and cancer location were associated with turquoise module. Key genes of TCP1, COQ3, PTMA and MAPRE1 might be potential prognostic markers for ESCC.

Discussion: Differentially expressed genes and key modules contributing to initiation and progression in ESCC were identified by WGCNA. These findings provide novel insights into the mechanisms underlying the initiation, prognosis and treatment of ESCC.

Strenuous occupational physical activity: Potential association with esophageal squamous cell carcinoma risk

Objective:

The impact of recreational physical activity (RPA) on cancer risk has been extensively studied. However, the association of occupational physical activity (OPA), which differs in dose and intensity from RPA, with different cancers including esophageal squamous cell carcinoma (ESCC), has received less attention.

Materials and methods:

We conducted a hospital-based case–control study in Kashmir, India, majorly a rural population, to evaluate the association of OPA with ESCC risk. Histopathologically confirmed 703 ESCC cases and 1664 controls, individually matched to the respective cases for age, sex and district of residence, were recruited.

Main outcome measures:

Information on type, duration and intensity of physical activity was obtained in face-to-face interviews with participants using a structured questionnaire. Conditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). Body mass index was unable to be accounted for in the analysis.

Results:

A high level of OPA was associated with increased ESCC risk (OR = 2.17, 95% CI; 1.41–3.32), compared to subjects with moderate OPA. The association with ESCC risk was stronger in strenuous workers (OR = 3.64, 95% CI; 2.13–6.20). The association of strenuous OPA with ESCC risk persisted only in subjects that were involved in strenuous activities for equal to or greater than five days/week.

Conclusions:

Our study suggests a possible association of strenuous OPA with ESCC risk. Although our results were adjusted for multiple factors, including indicators of socioeconomic status, more replicative occupational epidemiological studies are needed to rule out any residual confounding.

A Distinct Epidemiologic Pattern of Precancerous Lesions of Esophageal Squamous Cell Carcinoma in a High-risk Area of Huai'an, Jiangsu Province, China

Better understanding of esophageal precancerous lesions (EPL) can inform prevention strategies for esophageal squamous cell carcinoma (ESCC). Here, a cross-sectional epidemiologic study based on the Early Diagnosis and Early Treatment Project of Esophageal Cancer database from 2011 to 2017 was performed to fully investigate and characterize the epidemiology of EPL in rural Huai'an District. Data of 11,518 participants ages 35-75 years were collected through face-to-face interviews by questionnaire. Participants underwent a routine endoscopy examination, tissues were biopsied, and diagnosed according to the histologic criteria of dysplasia. Unconditional univariate and multivariate logistic regression analyses were performed to obtain crude and adjusted odds ratios and corresponding 95% confidence intervals, respectively. A total of 667 subjects were diagnosed with EPL. Factors associated with an increased risk of EPL included: drinking shallow well water and surface water, irregular diet, excessive smoking, exposure to secondhand smoke, consumption of corn, corn flour, pickled food, fried food, and hot food, and having a history of digestive system diseases. In addition, liquor use, but not other alcohol types, contributed to risk of EPL. Consumption of deep well water and vegetables, fruits, and animal livers were associated with lower EPL risk. This study suggested a completely distinct pattern that alcohol use plays only a minor role in EPL and excessive tobacco use shows a significant association in rural Huai'an District, while eating habits and environmental exposure may be the dominant factors. This work may be promising to provide scientific evidence to support primary prevention of ESCC in this region.

Biomass fuel as a risk factor for esophageal squamous cell carcinoma: a systematic review and meta-analysis

BACKGROUND

The link between use of solid biomass fuel (wood, charcoal, coal, dung, and crop residues) for cooking and/or heating and esophageal squamous cell carcinoma (ESCC) is inconclusive.

OBJECTIVE

We systematically reviewed the literature and performed a meta-analysis to determine whether cooking fuel type influences esophageal squamous cell carcinoma.

METHODS

We searched MEDLINE, EMBASE, Web of Knowledge and Cochrane Database of Systematic Reviews for studies investigating cooking fuel and ESCC from 2000 until March 2019. We performed random effects meta-analysis stratified by the continent, World Bank's country income classifications and fuel type and calculated pooled odds ratios and 95% CIs for the risk of esophageal squamous cell carcinoma in biomass fuel users compared with non-users.

RESULTS

Our analysis included 16 studies (all case-control) with 16,189 participants (5233 cases and 10,956 controls) that compared risk of ESCC among those using nonsolid fuels and biomass fuels. We found use of biomass fuel was associated with Esophageal squamous cell carcinoma with a pooled odds ratio (OR) 3.02 (95% CI 2.22, 4.11, heterogeneity (I2) = 79%). In sub-group analyses by continent, Africa (OR 3.35, 95%CI 2.34, 4.80, I2 = 73.4%) and Asia (OR 3.08, 95%CI 1.27, 7.43, I2 = 81.7%) had the highest odds of ESCC. Use of wood as fuel had the highest odds of 3.90, 95% CI 2.25, 6.77, I2 = 63.5%). No significant publication bias was detected.

CONCLUSIONS

Biomass fuel is associated with increased risk of Esophageal squamous cell carcinoma. Biomass fuel status should be considered in the risk assessment for Esophageal squamous cell carcinoma.

Systematic review: the etiology of esophageal squamous cell carcinoma in low-income settings

Esophageal carcinoma causes over 380 000 deaths per year, ranking sixth worldwide in mortality amongst all malignancies. Globally, the squamous cell subtype is most common and accounts for 80% of esophageal cancers. Nonetheless, esophageal squamous cell carcinoma is much more poorly understood than esophageal adenocarcinoma, including what is driving such high prevalences, why it often presents in young patients, and shows such marked geographical delineations Areas covered: The current literature was searched for articles focusing on aetiopathogenesis of squamous cell esophageal carcinoma via a systematic review, particularly in low-resource settings. This was supplemented by papers of interest known to the authors. Expert commentary: Current putative mechanisms include polycyclic aromatic hydrocarbons, nitrosamines, acetaldehyde, cyclo-oxygenase-2 pathways, androgen and their receptor levels, as well as smoking & alcohol, micronutrient deficiencies and diet, mycotoxins, thermal damage, oral hygiene and microbiotal factors, inhaled smoke, viral infections such as HPV, and chronic irritative states. Etiology is likely multifactorial and varies geographically. Though smoking and alcohol play a predominant role in high-income settings, there is strong evidence that mycotoxins, diet and temperature effects may play an under-recognized role in low and middle-income settings.

Identification of the key transcription factors in esophageal squamous cell carcinoma

Background

Esophageal cancer (EC) is a common human malignancy worldwide. Esophageal squamous cell carcinoma (ESCC) is the predominant subtype in China. The tumorigenesis mechanism in ESCC is unclear. The aim of this study was to identify key transcription factors (TFs) in ESCC and elucidate the mechanism of it.

Methods

A total of ten published microarray datasets of ESCC was downloaded from the Gene Expression Omnibus (GEO). Then, bioinformatics analyses including differentially expressed genes (DEGs) analysis, gene ontology (GO) annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, TFs-genes regulatory network construction was performed. Quantitative real-time polymerase chain reactions (qRT-PCR) were used to detect the expression levels of TFs and DEGs in ESCC. The association between stage and TFs and the association between survival and TFs were evaluated based on The Cancer Genome Atlas (TCGA), respectively.

Results

A total of 1,248 dysregulated genes were selected as DEGs in ESCC. A total of 26 TFs and corresponding target-genes were identified. The ESCC-specific transcriptional regulatory network was constructed. The network was consisted of 882 edges and 631 nodes. BRCA1, SOX10, ARID3A, ZNF354C and NFIC had the highest connectivity with DEGs, and regulated 92, 89, 82, 79 and 78 DEGs in the network, respectively. All these 1,248 DEGs were significantly enriched in cell cycle, DNA replication and oocyte meiosis pathways. The qRT-PCR results were consistent with our microarray analysis. High expression of SREBF1 and TFAP2A were significantly correlated with the longer overall survival time of patients with ESCC.

Conclusions

BRCA1, SOX10, ARID3A, ZNF354C and NFIC might be the key TFs in carcinogenesis and development of ESCC by regulating their corresponding target-genes involved in cell cycle, DNA replication and oocyte meiosis pathways. SREBF1 and TFAP2A may be two potential prognostic biomarkers of ESCC.

CYP1A2*1F Gene Variant, Alkaline Salt Tea Intake and Risk of Esophageal Squamous Cell Carcinoma

Unlike many other cancers, the relationship of CYP1A2*1F (rs762551) polymorphism with esophageal squamous cell carcinoma (ESCC) risk has not been assessed so far. To evaluate its association with ESCC, we conducted a case control study in Kashmir, India, a high risk region. We recruited 404 histopathologically confirmed ESCC cases and 404 controls, individually matched for sex, age and residence to the respective cases. Information was obtained on dietary, lifestyle and environmental factors in face to face interviews using a structured questionnaire from each subject. Genotypes were analyzed by polymerase chain reaction, restriction fragment length polymorphism and sequencing randomly selected samples. Conditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). We found that mutant genotype (AA) of CYP1A2*1F polymorphism was associated with ESCC risk (OR = 3.11; 95% CI: 1.72-5.36). A very strong ESCC risk was observed in subjects who drank >1250 ml of salt tea daily and harbored mutant genotype of CYP1A2*1F (OR = 14.51; 95% CI: 5.33-39.47). The study indicates that CYP1A2*1F polymorphism is associated with ESCC risk and the risk is modified in salt drinkers. However, more replicative and mechanistic studies are needed to substantiate the findings.

Smoking and alcohol drinking in relation to the risk of esophageal squamous cell carcinoma: A population-based case-control study in China

Previous results regarding the associations between esophageal squamous-cell carcinoma (ESCC) risk and smoking/alcohol drinking in high-risk areas are inconsistent. We performed a large population-based case-control study from 2010 to 2013 in a high-incidence area of China, and enrolled 1353 ESCC cases and 1961 controls. Data regarding smoking and alcohol drinking were collected via face-to-face interviews using a structured questionnaire. Odd ratios (ORs) with 95% confidence intervals (CIs) were estimated using unconditional logistic regression models. After adjusting for alcohol drinking and other potential confounders, male heavy smokers (i.e., those who started smoked more than 20 cigarettes per day or 40 pack-years, or started smoking early), showed a moderately increased risk for ESCC; however, current smoking was not associated with an increased risk. Alcohol drinking among males significantly increased the risk for ESCC (OR = 2.20, 95%CI:1.79~2.70). We observed increasing excess ESCC risks with decreasing age at behavior initiation as well as with increasing duration and intensity of alcohol intake, which were particularly evident among current smokers. In contrast, neither smoking nor alcohol drinking was not associated with ESCC risk among females. In conclusion, alcohol drinking shows a monotonic dose-response relationship with ESCC risk among men, and this relationship is particularly evident among smokers.

Alcohol, smoking and risk of oesophago-gastric cancer

Oesophago-gastric cancers (oesophageal and gastric cancers) are common, highly fatal cancers. Oesophageal squamous cell carcinoma (OSCC) and oesophageal adenocarcinoma (OAC) are the two main histological subtypes of oesophageal cancer. Globally, OSCC remains the most common histological subtype of oesophageal cancer, with the highest burden occurring along two geographic belts, one from north central China through the central Asian republics to northern Iran, and one from eastern to southern Africa. In Western countries, the incidence of OAC has increased dramatically over the past 40 years. OAC is now the most common subtype of oesophageal cancer in the United States, United Kingdom, and Australia. Approximately 90% of gastric cancers are adenocarcinoma, with the majority of cases diagnosed in Eastern Asia, Eastern Europe, and some Latin American countries. Smoking is an established risk factor for both oesophageal (OSCC and OAC) and gastric cancers. Alcohol consumption, however, is strongly associated with increased risk of OSCC and probably increases the risk of gastric cancer, but is not associated with OAC. Here, we review the current epidemiological evidence on associations between alcohol consumption, smoking and the risk of developing oesophago-gastric cancer, and emphasize the importance of focusing efforts on controlling the worldwide burden of oesophago-gastric cancer by reducing alcohol and tobacco use.

A risk factor-based model for upper aerodigestive tract cancers in India: predicting and validating the receiver operating characteristic curve

BACKGROUND

A study was conducted to develop and validate a screening model using risk scores to identify individuals at high risk for developing upper aerodigestive tract (UADT) cancers in an Indian population.

METHODS

A hospital-based case-control study (n = 480) was conducted in Pune, India. We assessed risk factors for UADT cancers by administering a questionnaire through face-to-face interviews. We developed a risk factor model based on the statistically significant risk factors in multiple logistic regression. A total, single risk score was calculated per individual based on the adjusted odds ratio for each of their risk factors. Standard receiver operator characteristic curve was plotted for the total score and the presence of UADT cancers. The stratification ability of the model was determined using the c-statistic. The optimal criterion value was determined at the point on curve at which the Youden's index was maximal. Confidence intervals were calculated by bootstrapping.

RESULTS

Total risk score for each individual ranged from 0 to 26. Area under the receiver operating characteristic curve (95.8; P < 0.001) suggests strong predictive ability. A risk score criterion value of ≤10 produced optimal sensitivity (93.5%), specificity (71.1%), false-positive rate (28.8%), false-negative rate (6.4%), positive predictive value (74.8%), and negative predictive value (96.6%).

CONCLUSION

This risk factor-based model has the potential of satisfactorily screening and detection of UADT cancers at its early stage in a high-risk population like India. The identified at-risk individuals can then be targeted for clinical examination and for focused preventive/treatment measures at the hospital.