smoking tobacco not only predisposes to the development of disease , it increases disease severity and treatment failure rates . for these reasons ,
smoking cessation particularly benefits those patients who have smoking - related cancers such as head and neck or lung cancer and those who are diagnosed with curable disease .   
cigarette smoking and alcohol consumption are well - established risk factors for developing squamous cell carcinoma of the head and neck .
furthermore , a number of studies have revealed an association between tobacco carcinogens and the molecular progression of squamous cell carcinoma of the head and neck . in countries with a high prevalence of smoking ,
furthermore , the increased incidence of lung cancer from smoking is proportional to the length and intensity of smoking history .
smoking cessation before diagnosis reduces the risk of developing a primary tumour of all major histological types of lung carcinoma .  
prolonged tobacco smoking in cancer patients has many adverse effects during the oncology treatment plan as well .
studies with head and neck and lung cancer patients demonstrate that tobacco smoking reduces survival time   and increases the risk of a recurrence or a second primary tumor [ 4 , 5 ] .
smoking also reduces the efficacy of radiotherapy in head and neck cancer patients , as smokers have a lower rate of complete response and poorer 2-year survival rate than nonsmokers and those who quit prior to treatment . tobacco smoking also exacerbates and prolongs radiotherapy induced complications such as mucositis , dry mouth , loss of taste , voice , impaired pulmonary function , wound healing , as well as tissue and bone necrosis [ 4 , 7 ] . despite these adverse health effects , 23% to 35% of head and neck cancer patients [ 5 , 810 ] and 13% to 20% of lung cancer patients who smoked prior to diagnosis continue to do so after diagnosis .
comorbid conditions such as depression , disease - related anxiety , and alcohol abuse often make cessation challenging .
the diagnosis of cancer allows an opportunity for patients to review and change their lifestyle habits [ 11 , 12 ] .
the earliest descriptions of smoking cessation interventions in the health care setting are described in a summary report by schwartz .
interventions may be hospital - based , community - based , or based on individual counseling .
current smoking cessation interventions can be either pharmacological , nonpharmacological or a combination of both .
examples of effective approaches include identifying tobacco use in patients , motivating them to quit and supporting them to quit through brochures and pamphlets , counseling , pharmacotherapy as well as regular followup . despite the substantial benefits of tobacco cessation in cancer patients ,
there is still a relative paucity of data on how to best achieve cessation in this population .
the aim of our study was to systematically review the literature to summarize tobacco cessation interventions for cancer patients and the associated smoking cessation rates as a consequence of these interventions .
this systematic review was performed in accordance with a predetermined protocol consisting of eligibility criteria , a search strategy , outcomes , and statistical analysis .  
our primary aim was to perform a pooled analysis of smoking cessation rates if appropriate .    
the literature was searched using ovid medline ( 1950 through november 2010 ) , embase ( 1980 to november 2010 ) , and the cochrane library ( cochrane database of systematic reviews ( 2010 issue 12 ) .
relevant articles and abstracts were selected and reviewed , and the reference lists from these sources and recent review articles or meta - analyses were searched for additional publications .   the literature search of the electronic databases combined disease specific keywords ( cancer , neoplasm , and malignancy ) with outcome specific keywords ( tobacco cessation , smoking cessation , nicotine cessation , quit rates , patient education , and patient intervention ) for the following study designs and publication types : retrospective studies , prospective cohort studies , randomized controlled trials ( rcts ) , systematic reviews , and meta - analyses .
the literature search was not limited for study design or publication date to ensure all relevant published articles were captured .
articles were included in the systematic review of the evidence if they were fully published reports or abstracts of randomized controlled trials ( rcts ) evaluating a tobacco smoking cessation intervention versus standard usual care in the adult smoking cancer population ( > 18 years of age ) . to be included ,
articles were excluded if they were published in a language other than english , did not discuss a tobacco cessation intervention , discussed nontobacco products without separation of data , or were in the pediatric population .
relevant data was extracted from fully published reports by two independent review authors using prescribed tables .
primary authors of included studies were contacted if further elaboration on data was needed [ 1 , 13 ] . where studies were duplicated , the larger data set was used for the analysis [ 13 , 18 ] .
statistical calculations were performed using the statsdirect software ( chesire , uk ) .   given that we analyzed prospectively gathered data from randomized trials , we calculated a pooled relative risk .
the relative risk was a ratio of the risk of tobacco cessation in the intervention group versus the risk of tobacco cessation in the control group .  
the relative risks were calculated where data was available by intention - to - treat analysis .  
pooled relative risks were calculated using the rothman - boice type of mantel - haenszel method assuming fixed effects .
the random - effects model of pooled relative risks was calculated using the dersimonian - laird method .
the decision to use either a random effects model or a fixed effects model was based on calculation of heterogeneity of the data using an i calculation . where heterogeneity of the data was large , a random effects model was used .
confidence intervals of the pooled relative risk were calculated using the greenland - robin variance formula .
eight studies [ 1 , 4 , 11 , 13 , 17 , 2022 ] were narrowed down through the search ( figure 1 ) .
all the studies identified were rcts in the adult smoking population which described a tobacco smoking cessation intervention and smoking cessation rates .
all published studies ( table 1 ) were rcts , which were either single center [ 11 , 13 , 17 , 21 , 22 ] or multicenter [ 1 , 4 , 20 ] .
the included studies did not show significant differences in baseline characteristics of mean age and gender distribution except in studies that included only head and neck patients [ 11 , 13 ] ( table 1 ) .
interventions were nonpharmacological ( cognitive behavioral therapy , self - help material , education modules , motivational interviewing ) , or pharmacological ( nicotine replacement therapy or bupropion ) ( table 2 ) . all studies evaluated tobacco smoking .
all the studies used self - reported rates of tobacco cessation .   in addition , some studies used biochemical verification as well for smoking cessation .
two of the studies used breath testing of carbon monoxide ( co ) [ 11 , 21 ] , two studies used urine cotinine levels [ 1 , 11 ] and two studies used saliva cotinine levels [ 13 , 17 ] where possible to confirm self - reported rates ( table 2 ) .    
cessation rates depending on randomization varied for each study at different followup times ( table 3 ) .
the studies were evaluated in two groups , one group with a shorter followup time , mean of 5 weeks [ 13 , 17 , 22 ] and the other group had a longer followup time of at least 6 months [ 1 , 4 , 11 , 20 ] .   in the second group ,
pooled rates were calculated from the 6 month abstinence rates in all studies except in one study which did not report a 6 month rate but only a 12 month rate .
schnoll et al'.s study   was excluded from the longer followup group and analysis due to a purely pharmacological intervention compared to the other studies in the other group which were combination interventions . for the purpose of pooling data ,
when we examined the shorter followup group , the pooled relative risk was calculated to be 1.16 ( 95% ci = 0.80 to 1.76 ) in the short followup group ( figure 2 ) .  
the longer followup group had a pooled relative risk of 1.19 ( 95% ci = 0.78 to 1.78 ) ( figure 3 ) .  
the pooled relative risk of the three most recent studies shows a result that is much more positive , with the relative risk achieving statistical significance .  
this pooled rate was calculated to be 1.42 ( 95% ci , 1.05 to 1.94 ) .
when necessary , authors were contacted to provide additional data to ensure an accurate data set .
the identified papers were methodologically sound with prospectively gathered data , randomized study populations , and suitable control groups .    
only one study   looked at a purely pharmacological approach to tobacco cessation while three studies had only a nonpharmacological approach [ 1 , 13 , 17 ] . four studies [ 4 , 11 , 20 , 22 ] had a combination approach of nicotine replacement therapy , counseling and/or cognitive behavioral study .
duffy et al .   looked at the combination of cognitive behavioral therapy in addition to bupropion and nicotine replacement therapy .
comparison of the confidence intervals of the calculated relative risks of the studies does not demonstrate a significant difference in tobacco smoking cessation rates between any of the different types of intervention .
similar to other systematic reviews , our analysis comprised of a relatively high heterogeneity of treatments and patient groups .
the studies were divided into two groups  short followup time ( mean 5 weeks ) and longer followup time ( 6 months ) .
while comparing the pooled relative risks of the two groups , it does not demonstrate a significant difference in the cessation rates despite the fact that a longer followup time would tend to represent better cessation rates .
however , considering the shorter followup times , it is difficult to state whether at 6 months , this group would continue to have the same cessation rates .  
when we examined the longer followup group , four studies were included [ 1 , 4 , 11 , 20 ] .  
this study examined a group of 186 head and neck cancer patients and utilized a nonpharmacological counseling - based approach .  
if this original study is excluded from the analysis , this long - term followup group does appear to yield a statistically significant effect due to a multi - modal cessation intervention .  
notably , these other three studies [ 4 , 11 , 20 ] were performed in the most recent decade and examined 705 patients with diverse oncologic diagnoses .   
furthermore , these three studies all included a pharmacological approach in addition to nonpharmacological intervention .
these differences may account for the reason that the pooling most recent studies reaches a statistically significant effect for smoking cessation intervention .  
in addition , the setting in which the cessation methods were offered are also different .
some studies counseled patients on smoking cessation during a postoperative hospital admission , while other interventions were provided in the clinics .
comparing the cessation rates of the individual studies does not demonstrate a significant difference in the cessation patterns based on setting .  
it is unlikely the self - reported rates would bias our review towards a negative result .  
when all studies are analyzed in the short and long - term , there was no statistical to a tobacco smoking cessation intervention in addition to usual care .   however , when examining the effect of a multifaceted approach ( pharmacological and nonpharmacological ) to smoking cessation , the analysis suggested a more positive result .
our review does not demonstrate a significant difference in tobacco smoking cessation rates through these interventions .
the data does , however , suggest that the combination of both pharmacological and nonpharmacological approaches may be more successful at achieving tobacco cessation .  
collaboration within the health - care team is paramount in implementing a smoking cessation intervention .
the significant benefits of tobacco cessation demand the oncology team continue to explore and investigate novel and known methods to help patients become tobacco - free .
 
 background . 
 tobacco smoking cessation interventions in the oncology population are an important part of comprehensive treatment plan . objectives . to evaluate through a systematic review smoking cessation interventions and cessation rates in cancer patients . 
 search strategy . 
 the literature was searched using medline , embase , and the cochrane library ( inception to november 2010 ) by three independent review authors . 
 selection criteria . 
 studies were included if tobacco smoking cessation interventions were evaluated and patients were randomized to usual care or an intervention . 
 the primary outcome measure was cessation rates . 
 data collection and analysis . 
 two authors extracted data independently for each paper , with disagreements resolved by consensus . 
 main results . the systematic review found eight rcts investigating smoking cessation interventions in the oncology patient population . 
 pooled relative risks were calculated from two groups of rcts of smoking cessation interventions based on followup duration . in both groups , the pooled relative risk did not suggest a statistically significant improvement in tobacco cessation compared to usual care . 
 conclusions . 
 our review demonstrates that recent interventions in the last decade which are a combination of non - pharmacological and pharmacological approaches yield a statistically significant improvement in smoking cessation rates compared to usual care . 
1. Introduction
2. Methods
3. Results
4. Discussion
5. Conclusion