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prostate cancer is a major health problem in the male population both in poland and europe . in 2012 , with the number of new cases in europe up to 416,730 ( representing 22.8% of all cancer cases in male population ) , pca placed first in terms of highest incidence of malignancy in men .
the awareness of suffering from prostate cancer ( pca ) is associated with poor psychological tolerance .
systematic progress in medicine , advances in diagnostic and therapeutic procedures , accompanied by an increase in life expectancy in the male population has lead to a growing number of patients with pca  newly diagnosed , currently treated or after therapy .
tools allowing for objective evaluation of patients qol , enabling tracking its changes during the course of the disease , as well as assessing the impact of different types of therapies on qol are encapsulated by the eortc questionnaires  the quality of life in patients with cancer ( qlq - c30 ) and quality of life specific to pca ( qlq - pr25 ) .
the former concerns the functional aspects of health related quality of life ( hrqol ) and frequently occurring symptoms in cancer patients .
the latter consists of multiple parts , assessing symptoms from the urinary and gastrointestinal tracts , sexual functions , and adverse effects of treatment . both were widely tested , and are regarded as reliable instruments in the quality of life measurement [ 36 ] .
the aim of this study was to assess the quality of life in a population of polish patients suffering from prostate cancer , stratified according to the stage of the disease .
this prospective , multicenter , observational study comprised 1080 patients , of whom 1047 ( 96.9% ) completed the study .
the research project received approval from the local ethics committee . according to our inclusion criteria we enrolled men over the age of 40 , with diagnosed prostate cancer , who were able to read polish and gave their informed consent to participate in the study .
108 physicians , providing outpatient practice all around poland were involved in the study , education , and data collection from the patients .
patients were divided into 3 groups according to the stage of the disease : localized , locally advanced and metastatic pca .
patients qol was assessed using the eortc questionnaire qlq - c30 comprised of 5 scales , which assess functional status ( physical functioning , role functioning , emotional functioning , cognitive functioning , social functioning ) , three symptom scales ( fatigue , nausea / vomiting , pain ) , and further , an overall assessment of the patient 's medical condition / quality of life . furthermore , the questionnaire evaluates six individual symptoms such as dyspnoea , insomnia , appetite loss , constipation , diarrhoea and financial difficulties as a consequence of the disease were evaluated .
the second questionnaire ( qlq - pr25 ) assesses the quality of life specific to pca .
it assesses symptoms from the urinary and gastrointestinal tract , sexual function , and adverse effects of treatment .
a high score on the functional scale represents a high / healthy level of functioning ; a higher score on symptom scales shows higher symptom expression / lower health level .
a difference of 510 points in the scores represents small change , 1020 points  moderate change and greater than 20 points 
the examination procedure consisted of patients filling out qlq - c30 and qlq - pr25 questionnaires , implementation of an educational program during the first visit , and afterwards re - evaluation of the quality of life based on the previously mentioned questionnaires after a period of three months .
the proportion of patients from the study group according to stage of disease : localized prostate cancer 377 ( 34.9%)locally advanced 516 ( 47.8%)metastatic disease 187 ( 17.3% ) patients . 
 
localized prostate cancer 377 ( 34.9% ) locally advanced 516 ( 47.8% ) metastatic disease 187 ( 17.3% ) patients .
the proportion of patients with prostate cancer by decades of life:<60 years of age 77 ( 7.6%)6070 years 296 ( 27.3%)7080 years 430 ( 40%)>80 years of age 271 ( 25.1% ) patients ( figure 1 ) 
  < 60 years of age 77 ( 7.6% ) 6070 years 296 ( 27.3% ) 7080 years 430 ( 40% ) > 80 years of age 271 ( 25.1% ) patients ( figure 1 ) age distribution in pca patients .
the highest qol scores ( 62 points ) were observed in patients with localized prostate cancer , while the lowest were recorded in the metastatic group ( 45 points ) . in locally advanced cancer general qol
was assessed as 56 points , placing it between the two other stages of pca .
physical , emotional , cognitive and social functioning , as well as functioning in roles , evaluated using qlq - c30 , exceeded 80 points for patients with localized cancer and was lower than 70 points in patients with metastatic disease ( p < 0.05 ) ( figure 2 ) .
fatigue , nausea , pain , shortness of breath , insomnia , loss of appetite , constipation , diarrhoea as well as financial problems were more frequent in patients with metastatic disease than in those with organ - confined disease ( p < 0.05 ) ( figure 3 ) .
assessment of qol , and physical , emotional , cognitive , and social functioning showed a statistically significant correlation with the stage of the disease ( p < 0.05 ) .
qlq - c30 symptoms scale depending on the stage of the disease . according to the qlq - pr25 , urinary and gastrointestinal tract symptoms , as well as side effects associated with hormone therapy , intensified with increasing tumour stage .
patients with localized cancer scored 22 on the urinary tract symptom scale , 7 on the gastrointestinal tract symptom scale and 17 points for adverse symptoms associated with androgen deprivation therapy . among those with locally advanced disease , point scores reached 26 , 10 and 24 respectively
were recorded , whereas patients suffering from generalized pca had the worst outcomes with 32 , 12 and 29 points respectively ( figure 4 ) .
level of sexual activity and sexual functioning were scored highest by patients with cancer localized to prostate , 22 and 44 points respectively .
the worst qol was reported by patients with locally advanced pca , 17 and 35 points respectively .
accordingly , metastatic disease placed in between with 19 and 40 points respectively ( figure 4 ) .
ours is by far the largest population - based study evaluating the quality of life among polish patients with prostate cancer .
previously published data confirmed the credibility of the questionnaires eortc qlq - c30 and qlq - pr25 in terms of reliability and validity , and confirmed their role as an accurate research tool used in the assessment of the quality of life . while no differences might have been seen in general hrqol disease - targeted measures ( sexual , urinary , bowel domains ) may differ significantly . according to a prior survey by j. dobruch et al .
furthermore , a significant number of detected cases of pca will not progress to clinically significant cancer .
the urologists need to focus their therapeutic effects not only on the absolute prolongation of their patients life , but also on simultaneous achievement of the best possible quality of life .
efforts must focus on minimizing the psychological distress , in order to prevent a decrease in the quality of life in patients undergoing treatment .
the treatment of prostate cancer reduces the assessed qol in all six scales of the qlq - pr 25 questionnaire .
the best qol is observed among patients undergoing active surveillance , while patients treated with chemotherapy evaluated their quality of life as being the lowest .
taking into consideration the side effects of localized pca treatment , radiotherapy seems to be at least as good a therapeutic option as radical prostatectomy .
, in our study group fatigue was one of most frequently reported symptoms in pca patients .
the results of our observations coincide with those conducted by vanagas et al . who analysed a group of 501 patients with prostate cancer .
the highest qol was found to be in cancer stage i according to nci classification ( from 72.2 on the social functioning scale to 88.9 in role functioning ) .
the lowest results on the functioning scales were observed among patients with stage iv cancer ( from 61.2 in emotional functioning to 72.7 in social functioning ) . in our study , the differences in the quality of life between localized and metastatic pca ranged between 10 and 20 pts , which according to the results of osoba , indicates a moderate impact on the quality of life [ 8 , 18 ] .
the evaluation of sexual activity in patients suffering from pca on the basis of qlq - pr25 revealed that the best results are in patients with localized cancer followed by patients with metastatic disease .
the worst symptoms were reported by patients with locally advanced cancer . this situation may be explained by the more aggressive therapeutic procedures introduced during the process of radical treatment ( radical prostatectomy without nerve - bundle preservation , radiotherapy ) in patients with locally advanced prostate cancer , compared to those suffering from cancer localized to the organ .
a greater chance of positive margins occurrence and local recurrence of the disease in locally advanced cancer compared to localized pca requires the use of complementary therapies .
this in turn leads to the accumulation of side effects and complications associated with implemented therapeutic methods .
the hormone therapy applied in metastatic cancer has less impact on the quality of patient 's sex life in comparison with the treatment carried out in locally advanced cancer .
the assessment of the quality of life , physical , emotional , cognitive , and social functioning showed a statistically significant correlation with the stage of the disease .
the highest qol , as assessed with the qlq - c30 , was reported by patients with localized prostate cancer , while the lowest scores were observed in the metastatic group .
sexual activity and sexual functioning were scored highest by patients with localized cancer , with the lowest scores reported among patients with locally advanced tumor .
the knowledge of changes in qol in patients with prostate cancer can help to inform choice of therapy , and thus lead to greater acceptance of side effects and optimization of the patient - doctor relation .
introductionrecent advances in treatment have led to the prolongation of life among patients with prostate cancer ( pca ) , which implies greater interest in the issue of the quality of life ( qol ) in patients who undergo treatment . 
 the quality of life of patients with cancer questionnaire ( qlq - c30 ) and the quality of life questionnaire specific to pca ( qlq - pr25 ) are tools used worldwide to conduct research on this subject . in our study we assessed the quality of life in a population of polish patients suffering from prostate cancer . 
 differences in the quality of life depending on the stage of the disease were highlighted.material and methodswe conducted a prospective , multicenter , observational study using the qlq - c30 and qlq - pr25 questionnaires in a group of 1047 patients.resultsthe highest qol scores ( according to the qlq - c30 questionnaire ) were observed in patients with localized prostate cancer , while the lowest were recorded in the metastatic group . 
 sexual activity and sexual functioning assessed on the basis of qlq - pr25 was best in the group of patients suffering from localized prostate cancer , and the worst in patients with locally advanced pca.conclusionsthe assessment of qol showed a significant correlation with the stage of the disease . 
 sexual activity and sexual functioning were the best in patients with localized cancer ; worst among patients with locally advanced tumor .