***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE Complaints of cognitive dysfunction are frequent among cancer patients . Many studies have identified neuropsychological compromise associated with cancer and cancer therapy ; however , the neuropsychological compromise was not related to self-reported cognitive dysfunction . In this prospect i ve study , the authors examined if confounding factors masked an underlying association of self-perceived cognitive function with actual cognitive performance . Determinants of self-perceived cognitive dysfunction were investigated . METHODS Self-perceived cognitive function and cognitive performance were assessed before treatment , at the end of treatment , and 1 year after baseline in 101 breast cancer patients r and omized to st and ard versus intensified chemotherapy .  Linear mixed-effects models were applied to test the relationships of performance on neuropsychological tests , patient characteristics , and treatment variables to self-reported cognitive function . Change of cognitive performance was tested as a predictor of change in self-reports . RESULTS Self-perceived cognitive function deteriorated during chemotherapy and had partially recovered 1 year after diagnosis . The personality trait negative affectivity , current depression , and chemotherapy regimen were consistently related to cognitive self-reports . No significant associations with performance in any of the 12 cognitive tests emerged . Change of cognitive performance was not reflected in self-reports of cognitive function . CONCLUSIONS Neuropsychological compromise and self-perceived cognitive dysfunction are independent phenomena in cancer patients . Generally , cancer-associated neuropsychological compromise is not noticed by affected patients , but negative affectivity and treatment burden induce pessimistic self- appraisal s of cognitive functioning regardless of the presence of neuropsychological compromise . Clinicians should consider this when determining adequate therapy for patients who complain of ' chemobrain ' PURPOSE We previously evaluated fatigue , menopausal symptoms , and cognitive dysfunction in patients receiving adjuvant therapy for breast cancer and matched healthy women . Here we report assessment of these women 1 and 2 years later . PATIENTS AND METHODS Patients without relapse and controls were evaluated by the Functional Assessment of Cancer Treatment-General Quality of Life question naire , with subscales for fatigue and endocrine symptoms , and by the High Sensitivity Cognitive Screen . RESULTS There were 104 , 91 , and 83 patients and 102 , 81 , and 81 controls assessed at baseline and at 1 and 2 years , respectively . Median Functional Assessment of Cancer Treatment-Fatigue scores ( range , 0 to 52 ) for patients improved from 31 ( on chemotherapy ) to 43 and 45 at 1 and 2 years , respectively , but were stable in controls ( 46 to 48 ) . Median Functional Assessment of Cancer Treatment-Endocrine Symptoms scores ( range , 0 to 72 ) for patients improved from 57 ( on chemotherapy ) to 59 and 61 at 1 and 2 years , respectively , and were stable in controls ( 64 to 65 ) . Differences between patients and controls remained significant for these scales . The incidence of moderate-severe cognitive dysfunction by the High Sensitivity Cognitive Screen  decreased in patients from 16 % ( on chemotherapy ) to 4.4 % and 3.8 % and in controls from 5 % to 3.6 % and 0 % at 1 and 2 years , respectively . There were minimal differences between estrogen receptor-positive patients who started hormonal therapy ( mainly tamoxifen ) after chemotherapy and estrogen receptor-negative patients who did not . Differences in quality of life between patients and controls were significant only at baseline . CONCLUSION Fatigue , menopausal symptoms , and cognitive dysfunction are important adverse effects of chemotherapy that improve in most patients . Hormonal treatment has minimal impact on them The aim of this study was to investigate the influence of baseline quality of life ( QoL ) on survival in patients with advanced colorectal cancer . From 1992 to 1998 , four r and omised clinical trials in advanced colorectal cancer were conducted at this institution . The European Organization for Research and Treatment of Cancer- Quality of Life Core 30 ( EORTC-QLQ-C30 ) question naire was completed prior to the commencement of chemotherapy . Analyses were performed on median-dichotomised baseline Quality of Life ( QoL ) and clinical prognostic factors . Baseline QoL question naires were completed by 501 patients .  One-year survival was 38.3 and 72.5 % ( P<0.0001 ) for patients with global QoL scores below and above the median ( 67 ) , respectively . Other than cognitive functioning , fatigue , appetite , constipation , diarrhoea and financial domains , all QoL scales were significant independent predictors of survival ( P<0.035 ) . In the final model , the global QoL score remained highly significant as an independent predictor of survival ( P<0.0001 ) . Baseline QoL is a strong independent predictor of survival in patients with advanced colorectal cancer . Measurements should be routinely recorded in clinical trials to stratify cohorts and aid in trial comparison A subset of survivors has cognitive impairment after cancer treatment . This is generally subtle , but may be sustained . In October 2006 , the second international cognitive workshop was held in Venice . The workshop included neuropsychologists , clinical and experimental psychologists , medical oncologists , imaging experts , and patient advocates . The main developments since the first Cognitive Workshop in 2003 have been the following . ( i ) studies evaluating cognitive function in patients receiving chemotherapy for cancers other than breast cancer , and in patients receiving hormonal therapy for cancer . ( ii ) The publication of longitudinal prospect i ve studies which have shown that some patients already exhibit cognitive impairment on neuropsychological testing before receiving chemotherapy , and some patients have deterioration in cognitive functioning from pre- to postchemotherapy . ( iii ) Studies of the underlying mechanisms of cognitive impairment both in patients and in animal models . ( iv ) Use of structural and functional imaging techniques to study changes in brain morphology and activation patterns associated with chemotherapy . ( v ) At present cognitive research in cancer is limited by method ological challenges and the lack of st and ardization in neuropsychological studies . The current workshop addressed many of these issues and established an international task force to provide guidelines for future research and information on how best to manage these symptoms OBJECTIVES Changes in cognitive function have been identified in and reported by many cancer survivors . These changes have the potential to impact patient quality of life and functional ability . This prospect i ve longitudinal study was design ed to quantify the incidence of change in cognitive function in newly diagnosed ovarian cancer patients throughout and following primary chemotherapy . METHODS Eligible patients had newly diagnosed , untreated ovarian cancer and had planned to receive chemotherapy . Web-based and patient reported cognitive assessment s and quality of life question naires were conducted prior to chemotherapy , prior to cycle four , after cycle six , and six months after completion of primary therapy . RESULTS Two-hundred-thirty-one evaluable patients entered this study between May 2010 and October 2011 . At the cycle 4 time point , 25.2 % ( 55/218 ) of patients exhibited cognitive impairment in at least one domain . At the post-cycle 6 and 6-month follow up time points , 21.1 % ( 44/208 ) and 17.8 % ( 30/169 ) of patients , respectively , demonstrated impairment in at least one domain of cognitive function . There were statistically significant , but clinical ly small , improvements in processing speed ( p<0.001 ) and attention ( p<0.001 ) but not in motor response time ( p=0.066 ) , from baseline through the six-month follow up time period . CONCLUSIONS This was a large , prospect i ve study design ed to measure cognitive function in ovarian cancer . A subset of patients had evidence of cognitive decline from baseline during chemotherapy treatment in this study as measured by the web-based assessment ; however , changes were generally limited to no more than one domain OBJECTIVES To report on the longitudinal cognitive functioning of older women receiving adjuvant chemotherapy for breast cancer . DESIGN Neuropsychological and functional status testing were performed before chemotherapy and 6 months after chemotherapy . SETTING Cancer center . PARTICIPANTS Thirty-one patients aged 65 and older with Stage I to III breast cancer . Of the 31 patients enrolled , three refused post-testing , and 28 were evaluable . MEASUREMENTS The following domains of cognitive function were examined : attention ; verbal memory ; visual memory ; and verbal , spatial , psychomotor , and executive functions . RESULTS Participants had a mean age of 71 ( range 65 - 84 ) : 39 % Stage I , 50 % Stage II , and 11 % Stage III . The number of scores 2 st and ard deviations ( SDs ) below the norm were calculated for each patient before and 6 months after chemotherapy ; 14 ( 50 % ) had no change , 11 ( 39 % ) worsened , and three ( 11 % ) improved ( P=.05 ) . Seven patients ( 25 % ) experienced a decline in cognitive function , defined as a 1-SD decline from pre- to post-testing in two or more neuropsychological domains . Exploratory analyses revealed no significant difference between functional status , comorbidity , and depression scale scores and change in overall quality -of-life scores before and after chemotherapy . CONCLUSION In this cohort of older women receiving adjuvant chemotherapy , a subset experienced a decline in cognitive function from before chemotherapy to 6 months after chemotherapy . Further prospect i ve study is needed to confirm these observations and to identify the subgroup at special risk OBJECTIVE Several prospect i ve studies into the effects of adjuvant systemic therapy on cognitive functioning suggest that a proportion of breast cancer patients show cognitive deficits already before the start of systemic therapy . Owing to , among others , method ological inconsistency , studies report different rates of this pre-treatment cognitive impairment . We examined the impact of four different criteria of cognitive impairment and two types of reference groups ( a study -specific healthy reference group versus published normative data ) on the prevalence of cognitive impairment . METHODS Two hundred and five postmenopausal breast cancer patients underwent a battery of neuropsychological tests before the start of endocrine therapy , 124 healthy subjects underwent the same tests .  Proportions of cognitive impaired patients were calculated for each of four criteria for cognitive impairment , using ( 1 ) study -specific healthy controls and ( 2 ) published norms of healthy controls as reference groups . RESULTS The prevalence of cognitive impairment varied greatly with the strictness of the criterion , as expected , but also was dependent on the reference group used . Cognitive impairment , relative to published norms , ranged from 1 % for the strictest to 36.6 % for the less strict criterion , cognitive impairment relative to study -specific healthy controls , ranged from 13.7 to 45.4 % for the same criteria . CONCLUSION This study highlights contrasting proportions of cognitive impairment by using different criteria for cognitive impairment and different reference groups . (Dis)advantages of the methods using a criterion for cognitive impairment , and of the use of published norms versus a study -specific reference group are discussed BACKGROUND Although high-dose chemotherapy is rapidly gaining acceptance as a treatment option for a number of cancers , the long-term toxic effects of such therapy are a concern . Cognitive deficits ( e.g. , problems with memory and concentration ) are not uncommon after chemotherapy , but they have not been documented systematic ally . In this study , we assessed the prevalence of cognitive deficits in a group of patients with high-risk breast cancer who were r and omly assigned to receive either high-dose or st and ard-dose adjuvant chemotherapy plus tamoxifen  , and we investigated whether high-dose chemotherapy impaired cognitive functioning more than st and ard-dose chemotherapy . METHODS Cognitive functioning was evaluated by use of a battery of neuropsychologic tests . In addition , patients were interviewed with regard to cognitive problems , health-related quality of life , anxiety , and depression . Results from patients who received adjuvant systemic therapy were compared with results from patients who had early stage breast cancer not treated with such therapy ( control patients ) . RESULTS The study population consisted of 34 patients treated with high-dose chemotherapy plus tamoxifen , 36 patients treated with st and ard-dose chemotherapy plus tamoxifen , and 34 control patients . For all patients , the average time since the completion of last nonhormonal therapy was 2 years . Cognitive impairment was found in 32 % of the patients treated with high-dose chemotherapy , in 17 % of the patients treated with st and ard-dose chemotherapy , and in 9 % of the control patients . In comparison with the control patients , patients treated with high-dose chemotherapy appeared to have an 8.2-times higher risk of cognitive impairment ( odds ratio ; 95 % confidence interval [ CI ] = 1.8 - 37.7 ) ; in comparison with the patients who received st and ard-dose chemotherapy , this risk of impairment was 3.5-times higher ( 95 % CI = 1.0 - 12.8 ) . CONCLUSION High-dose chemotherapy appears to impair cognitive functioning more than st and ard-dose chemotherapy .  Central nervous system toxicity may be a dose-limiting factor in high-dose chemotherapy regimens The current study sought to delineate prospect ively the rates and clinical course of emotional distress , cognitive 
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There was , however , only limited testing of the relationships between quantifiable cognitive dysfunction and HRQoL domains .
CONCLUSIONS This review suggests that in patients with solid tumours , where there is a relationship between chemotherapy treatment and cognitive impairment , the type and level of cognitive decline does not consistently appear to affect such patients ' HRQoL. This could be partly explained by variations in study design , measures used , definitions of cognitive impairment , varying measurement time frames , small sample sizes , and differences in disease severity and type of treatment regimes