esophageal cancer ( ec ) is the eight most common cancer worldwide , accounting for 3.2% of total new cases in 2012.(1 ) about 80% cases of ec worldwide occur in less developed regions.(2 ) according to globocan 2012 estimate , in india , there were 42,000 new cases of ec , the incidence being 4.13% of all new cancer cases , and 39,000 deaths were caused due to ec.(1 ) acharya tulsi regional cancer treatment & research institute , bikaner , rajasthan is a regional cancer center witnessing a large number of cancer patients from northwest india . despite various advances in the treatment of ec ,
it is one of the least responsive tumors to cancer therapy , and the overall prognosis remains poor .
the ratio between mortality to incidence is about 0.88 , more than 80% of the cases die within 2 years of diagnosis even in developed nations.(3 ) it is the nation 's most common malignancy involving the gastrointestinal tract.(4 ) in north america and western europe , alcohol and tobacco use are the major risk factors for squamous cell carcinoma ( scc ) , accounting for 8090% of cases.(5 ) diets of scant amounts of fruits , vegetables , and animal products are associated with increases in scc.(6 ) other risk factors associated with ec include plummer - vinson syndrome ( a condition characterized by iron - deficiency anemia and low riboflavin levels ) , achalasia , and tylosis.(7 ) in india , ec is being reported in increasing numbers from assam , kashmir , tamil nadu , karnataka , and kerala.(8 ) no literature is present from northwest india about the etiopathology of ec .
therefore , it is important to understand various aetiopathological factors associated with ec to find out various schemes for primary prevention of the disease . in this clause , we have reviewed the sociodemographic parameters of the patients with ec who visited the oncology department of our center in the last 10 years .
this is a retrospective analysis of medical records of the cancer patients registered in the regional cancer center of northwest india from january 2003 to december 2012 .
being a retrospective study , no ethical approval was required for the study as all the patients were treated with the standard departmental protocol . for extracting the data ,
the computerized data , hard copies of the files , and also the radiotherapy files of the patients were reviewed .
a total of 55,242 patients with a variety of malignancies were registered in the 10-year duration . out of this ,
the sociodemographic parameters including age , gender , locality , socioeconomic status , religion , education , occupation , and the addiction patterns of the patients were studied .
nonsmokers were defined as having smoked fewer than 100 cigarettes in their lifetime or less than one cigarette per day for 6 months or more .
all others were counted as smokers for the purpose of recording in the history sheet . to assess alcohol consumption ,
subjects were asked about their usual intake of beer , wine , and liquor from the age at which they started drinking at least one alcoholic beverage per month .
modified bg prasad classification(9 ) was used to assess the socioeconomic status of the patients as per the institutional policy . to calculate odds ratio ( or ) for smoking ,
the data of global adult tobacco survey ( india ) was used to define the control population.(10 ) the data from global survey on alcohol and health data by world health organization ( who ) region was utilized to calculate or for alcohol abuse.(11 ) all the recorded data was entered in windows excel sheet and imported to the statistical software to perform the calculations .
statistical calculations were performed used statistical package for social sciences ( spss ) for windows version 20.0 ( ibm corp . ,
out of 55,742 patients registered in our hospital , 3,667 were diagnosed to have ec .
53.4% patients were males with male : female ratio of 1.15:1 , indicating almost similar incidence of ec in males and females of northwest india .
the mean age was 54.6  11.7 years ; 66.2% of the patients were illiterate and 48.6% belonged to the low socioeconomic status ; 41% cases were of > 60 years age , while 3.4% of the patients were of 30 years ; and 76% of the patients came from the rural areas .
the primary location of the disease was 19.4 , 43.9 , and 28.9% in upper , middle , and lower third of the esophagus , respectively .
squamous cell histology was identified in 75.6% of the patients , while 18% patients had adenocarcinoma .
smoking was identified as a risk factor in 48% of the patients with bidi as the most commonly ( 26% ) smoked form of the tobacco , 25% of the patients were addicted to alcohol , while 11% had the habit of chewing tobacco .
strong associations was observed between smoking and ec ( or = 5.7 , 95% confidence interval ( ci ) = 5.36.1 ) .
alcohol abuse was also associated with increased risk of ec ( or = 2.7 , 95% ci = 2.13.3 ) .
ec is a disease with poor prognosis with approximately half of the patients presenting with unresectable or metastatic disease , thus cure rate of more than 15% are seldom achieved .
most of the western literature has reported male to female ratio of 4:1.(1213 ) however , in our study , this ratio is 1.15:1 , thus indicating a higher incidence of ec in females of northwest india . using the interactive cancer atlas which is a project of the national cancer registry programme , it was found that highest age adjusted incidence rate of ec ( international classification of diseases ( icd)-10 : c15 ) in females of india is in east khasi hills district of meghalaya ( 10.8 per 100,000 population ) ; while for males , it is 9.9 per 100,000 at the same place.(14 ) however , for males , this figure is highest in aizawl , mizoram ( 26.7 per 100,000 ) .
studies from south india have reported a ratio of 2:1.(1516 ) another study from western india observed a ratio of 1.4:1.(17 ) kamangar et al .
, reviewed the epidemiological pattern of ec in northeastern india and reported 1:1 ratio in golestan province.(3 ) the epidemiologic feature of equally high incidence of ec among females is a rare one ; such ratios have also been reported in linxian , china.(18 ) one common feature of these areas of the world with 1:1 male to female ratio is high registry reported rate of 100 per 100,000 population.(1920 ) very high risks and this unusual incidence pattern may indicate the presence of a strong risk factor that is shared by both the genders.(3 ) thus , it can be inferred that the areas with high prevalence of ec have nearly equal ratio of females and males affected by the disease . in our study , 3.46% patients were of 30 years .
it has been found that ec is rare in individuals younger than age 30 in both low and high incidence areas ; ec cases in those 30 years of age in northern china , northeastern iran , and the surveillance , epidemiology , and end results ( seer ) registries in the us account for 0.7 , 1 , and 0.5% of cases , respectively.(212223 ) another indian study by chitra et al .
, also reported similar age patterns with 5% cases below the age of 40 years with majority 62% cases of age group 4160 year.(4 ) in the us , the mean age of ec patients at diagnosis is 68 years , while it was 54.6 years in our study.(18 ) in our study , about two - third of the ec patients were illiterate and half belonged to low socioeconomic status as per the modified bg prasad scale .
sehgal et al . , also reported that the majority ( 63% ) cases were illiterate and 59.5% from lower socioeconomic status.(16 ) thus , our data are in agreement with already published literature .
this may stem from the fact that most of the patients visiting our cancer center belong to the rural area with farming being their main occupation .
another plausible explanation of this observation may be the use of organophosphorus pesticides in farming practices in patients coming from sriganganagar district of rajasthan and patients of punjab and haryana . however , exact comment on this etiology is not possible in the absence of specifically designed studies investigating the level of organophosphates in the serum of these patients .
such studies will further provide insight into the carnal knowledge of pesticides with cancer . in our study , 19.4% patients had the malignancy of upper third of the esophagus ; 44% patients had middle and 29% had carcinoma of the lower esophagus . in 7.6% of the patients ,
insufficient data were available to locate the exact site of the lesion . in another study by giri et al . , the percentage of patients with upper , middle , and lower third cancer was 9.66 , 40.57 , and 49.76% , respectively.(17 ) in our study , 18% patients had adenocarcinoma , while 75.6% had scc . in 6.4% cases ,
western literature has reported alcohol and tobacco use to the major risk factor for scc , accounting for 8090% of the cases.(5 ) in the present study also , the addiction of smoking was present in the majority ( 48% ) of the patients .
western reports have also described the relative risk of ec in relation to the amount of alcohol and tobacco consumed , including a relative risk of 155:1 when consuming 30 g / day of tobacco with 121 g / day of alcohol.(24 ) esophageal scc risk is 4.2 times higher in current smokers in europe compared with never - smokers , a meta - analysis showed.(25 ) another meta - analysis showed that esophageal ac risk is 2.3 times higher in people with 40 + years of cigarette smoking , compared with never - smokers.(26 ) in our study , the or for smoking and risk of ec was estimated to be 5.7 . since 75.6% patients in our study had scc , our data is in agreement with the results of these meta - analyses .
esophageal scc risk is 3038% higher in people who consume around 11.5 units of alcohol per day , 2.6 times higher in those who consume around 1.56 units of alcohol per day , and 5.5 times higher in those who consume 6 + units of alcohol per day , compared with never - drinkers.(2728 ) esophageal ac risk is not associated with alcohol drinking overall ( versus not drinking).(29 )
esophageal carcinoma is one of the important cancers prevalent in northwest india with a relatively higher incidence in females as compared to the findings of other studies .
the etiology in majority of patients is linked to tobacco and alcohol , thus , modification of lifestyle with limiting the use of addictions may be an effective strategy in the prevention of this dreaded and mostly incurable disease . a nationwide campaign is required to generate public awareness about this dreaded disease along with identifying the high risk population .
besides , further research is needed to identify the causes of geographical variations in the incidence of ec and its relatively higher incidence in females of northwest india .
 background : despite various advances in the treatment of esophageal cancer ( ec ) , being one of the least responsive tumors to cancer therapy , the overall prognosis remains poor . 
 therefore , it is significant to understand various sociodemographic factors associated with ec to find out various schemes for primary prevention of the disease.materials and methods : this is a retrospective analysis of medical records of the ec patients registered in the regional cancer center of northwest india from january 2003 to december 2012 . 
 the site of the disease and the histology were also recorded in addition to the various sociodemographic parameters.results:out of 55,742 patients registered in our hospital ; 3,667 were diagnosed to have ec . 
 male : female ratio was 1.15:1 . 
 the mean age was 54.6  11.74 years ; 66.15% of the patients were illiterate and 48.6% belonged to the low socioeconomic status . 
 smoking and alcohol consumption were identified as risk factors in 48 and 25.6% of the patients , respectively.conclusions:the etiology in majority of the patients is linked to tobacco and alcohol , thus , modification of life style with limiting the use of addictions may be an effective strategy in the prevention of this dreaded and mostly incurable disease . 
Introduction
Materials and Methods
Results
Discussion
Conclusions