Lack of a chemobrain effect for adjuvant FOLFOX chemotherapy in colon cancer patients. A pilot study

Quantifying chemotherapy-induced cognitive impairment in gastrointestinal cancer patients: A scoping review of methodological concerns in the literature

PURPOSE

Chemotherapy is one of the common treatments in cancer management. However, chemotherapy-induced cognitive impairment (CICI) is one notable side effect that can greatly impact a patient's quality of life. Literature on CICI in gastrointestinal (GI) cancers are few and inconsistent. This review aims to identify the methodological differences in such studies.

METHODS

A systematic search was performed in four electronic databases. All peer-reviewed primary literature published in English that evaluated cognitive-related functioning scores related to chemotherapy in GI cancer patients were included. Information about each study such as CICI findings, study limitations, methodology, and sample characteristics was extracted and synthesized.

RESULTS

A total of 19 studies were included. Evidence of CICI was found in 50.0% (8 of 16) and 62.5% (5 of 8) studies that used objective and subjective measures, respectively. Methodological differences such as groups used for comparison, instruments used, and assessment from the length of time since chemotherapy were highlighted between studies that did and did not find evidence of CICI.

CONCLUSIONS

This review suggests that the mixed findings can be attributed to the heterogeneous methodologies adopted in the evaluation of CICI in this field.

IMPLICATIONS FOR CANCER SURVIVORS

Further studies are necessary to establish the presence and chronicity of CICI, and in which groups of patients to facilitate targeted interventions and treatments.

A scoping review of cognitive assessment tools and domains for chemotherapy-induced cognitive impairments in cancer survivors

Backgrounds

Cancer survivors suffer from specific symptoms known as chemotherapy-induced cognitive impairments (CICIs). CICIs are difficult to capture with existing assessments such as the brief screening test for dementia. Although recommended neuropsychological tests (NPTs) exist, international consensus and shared cognitive domains of assessment tools are unknown. The aim of this scoping review was as follows: (1) to identify studies that assess CICIs in cancer survivors; (2) to identify shared cognitive assessment tools and domains by mapping the domains reported in studies using the International Classification of Functioning, Disability and Health (ICF) framework.

Methods

The study followed the recommendations made by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. We searched the following three databases through October 2021: PubMed, CINAHL, and Web of Science. Prospective longitudinal or cross-sectional studies were selected to determine CICI-specific assessment tools for adult cancer survivors.

Results

Sixty-four prospective studies (36 longitudinal studies and 28 cross-sectional studies) were included after checking for eligibility. The NPTs were divided into seven main cognitive domains. The specific mental functions were often used in the order of memory, attention, higher-level cognitive functions, and psychomotor functions. Perceptual functions were used less frequently. In some ICF domains, shared NPTs were not clearly identified. In some different domains, the same NPTs were used, such as the trail making test and the verbal fluency test. When the association between the publishing year and the amount of NPT use was examined, it was found that the amount of tool use tended to decline over the publication years. The Functional Assessment of Cancer Therapy-Cognitive function (FACT-Cog) was a shared consensus tool among the patient-reported outcomes (PROs).

Conclusion

Chemotherapy-induced cognitive impairments are currently gaining interest. Shared ICF domains such as memory and attention were identified for NPTs. There was a gap between the publicly recommended tools and the tools actually used in the studies. For PROs, a clearly shared tool, FACT-Cog, was identified. Mapping the domains reported in studies using the ICF can help in the process of reviewing consensus on which NPTs may be used to target cognitive domains.

Systematic review registration

https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000053710, identifier UMIN000047104.

The impact of surgery and adjuvant chemotherapy on health-related quality of life in patients with colon cancer: Changes at group level versus individual level

OBJECTIVE

This study aims to evaluate changes in health-related quality of life (HR-QoL) 1 year after surgical treatment in patients with primary resectable colon cancer and to assess whether changes at group level differ from changes at individual level. In addition, we assess which characteristics are associated with a decline of HR-QoL.

METHODS

Patients with primary resectable colon cancer who received surgical treatment and adjuvant chemotherapy if indicated were selected from the Prospective Dutch ColoRectal Cancer cohort (PLCRC). HR-QoL was assessed using EORTC-QLQ-C30 questionnaire before surgery and 12 months post-surgery. Outcomes were assessed at group and individual levels. Logistic regression analysis was conducted to assess which socio-demographic and clinical characteristics were associated with a clinically relevant decline of HR-QoL at 12 months.

RESULTS

Of all 324 patients, the baseline level of HR-QoL summary score was relatively high with a mean of 88.1 (SD 11.4). On group level, the change of HR-QoL at 12 months varied between -2% for cognitive functioning and +9% for emotional functioning. On individual level, 15% of all patients experienced a clinically relevant decline in HR-QoL summary score at 12 months. Older age, comorbidity burden or the reception of adjuvant chemotherapy was independently associated with a decline of HR-QoL in one of the functional subscales of EORTC-QLQ-C30 at 12 months.

CONCLUSION

Only trivial changes of HR-QoL were observed after colon cancer treatment on group level, whereas on individual level, at least 1 out of 10 patients experienced a decline of HR-QoL 12 months post-surgery. It is important to consider individual differences while making a treatment decision.

Four decades of chemotherapy-induced cognitive dysfunction: comprehensive review of clinical, animal and in vitro studies, and insights of key initiating events

Cognitive dysfunction has been one of the most reported and studied adverse effects of cancer treatment, but, for many years, it was overlooked by the medical community. Nevertheless, the medical and scientific communities have now recognized that the cognitive deficits caused by chemotherapy have a strong impact on the morbidity of cancer treated patients. In fact, chemotherapy-induced cognitive dysfunction or 'chemobrain'  (also named also chemofog) is at present a well-recognized effect of chemotherapy that could affect up to 78% of treated patients. Nonetheless, its underlying neurotoxic mechanism is still not fully elucidated. Therefore, this work aimed to provide a comprehensive review using PubMed as a database to assess the studies published on the field and, therefore, highlight the clinical manifestations of chemobrain and the putative neurotoxicity mechanisms.In the last two decades, a great number of papers was published on the topic, mainly with clinical observations. Chemotherapy-treated patients showed that the cognitive domains most often impaired were verbal memory, psychomotor function, visual memory, visuospatial and verbal learning, memory function and attention. Chemotherapy alters the brain's metabolism, white and grey matter and functional connectivity of brain areas. Several mechanisms have been proposed to cause chemobrain but increase of proinflammatory cytokines with oxidative stress seem more relevant, not excluding the action on neurotransmission and cellular death or impaired hippocampal neurogenesis. The interplay between these mechanisms and susceptible factors makes the clinical management of chemobrain even more difficult. New studies, mainly referring to the underlying mechanisms of chemobrain and protective measures, are important in the future, as it is expected that chemobrain will have more clinical impact in the coming years, since the number of cancer survivors is steadily increasing.

Systematic Review of Cognitive Impairment in Colorectal Cancer Survivors Who Received Chemotherapy

PROBLEM IDENTIFICATION

Cognitive impairment is a common and troublesome side effect experienced by many cancer survivors. It can have a significant impact on survivors' ability to function and enjoy a high quality of life. However, most cognitive impairment research has focused on breast cancer survivors, despite the high rates of colorectal cancer and the toxicity of treatment agents in some colorectal cancer chemotherapeutic regimens, which have been linked to cognitive impairment. This review provides a novel synthesis of what is known about cognitive impairment in colorectal cancer survivors.

LITERATURE SEARCH

CINAHL®, Cochrane Library, Embase®, PsycINFO®, and PubMed® were systematically searched by a health sciences librarian.

DATA EVALUATION

Data were extracted across studies; findings about the prevalence, severity, and correlates of cognitive impairment were synthesized.

SYNTHESIS

Across findings from 26 articles representing 24 independent studies, 13%-57% of participants had cognitive impairment. Potential demographic, physiologic, and psychological correlates of cognitive impairment were identified.

IMPLICATIONS FOR PRACTICE

Findings indicate a need to focus research and patient assessments on early identification of risk factors, assessing for existing cognitive deficits and testing interventions to decrease cognitive impairment in colorectal cancer survivors.

Neurocognitive Effects of Chemotherapy for Colorectal Cancer: A Systematic Review and a Meta-Analysis of 11 Studies

Purpose

Chemotherapy-related cognitive impairment (CRCI) is a controversial concept not much explored on colorectal cancer patients.

Materials and Methods

We identified 11 prospective studies: eight studies on 696 colorectal cancer patients who received chemotherapy and three studies on 346 rectal cancer patients who received neoadjuvant chemoradiotherapy. Standardized mean differences (SMDs) of neuropsychological test results and the cognitive quality-of-life scale were calculated using random effect models. A meta-regression was conducted to investigate the association between mean study population age and effect sizes.

Results

The association between chemotherapy and cognitive impairment was not clear in colorectal cancer patients (SMD, 0.003; 95% confidence interval, −0.080 to 0.086). However, a meta-regression showed that older patients are more vulnerable to CRCI than younger patients (β=–0.016, p < 0.001).

Conclusion

Chemotherapy has an overall positive negligible effect size on the cognitive function of colorectal patients. Age is a significant moderator of CRCI.

Systematic review of cognitive sequelae of non-central nervous system cancer and cancer therapy

PURPOSE

The aim of this review is to provide an updated overview of chemotherapy-related cognitive impairment (CRCI) in patients with cancer outside central nervous system (CNS), its incidence and prevalence, the cognitive pattern in neuropsychological studies, neuroimaging findings, and the relationship between chemobrain and aging. Methodological limitations of studies are also discussed.

METHODS

This review was guided by the PRISMA statement. The MEDLINE and Scopus databases were employed to search articles about CRCI in non-CNS cancer patients published from January 2004 to September 2019. Two types of research were reviewed: prospective studies addressing the effects of chemotherapy on cognition and systematic reviews about factors related with CRCI, also as neuroimaging findings and current available treatments.

RESULTS

Fifty-nine studies meeting the criteria were analyzed: 47 were longitudinal studies on cancer and cognition and 12 were reviews on risk factors, neuroimaging, and treatment. The majority of studies find cognitive impairment in patients with cancer treated with chemotherapy. The body of the literature on breast cancer is the most abundant, but there are also studies on colorectal, testicular, and lung cancer. Neuroimaging studies show changes in structure and activation in patients undergoing chemotherapy. Non-pharmacological treatment is effective for improving cognition and quality of life.

CONCLUSIONS

The occurrence of CRCI during the course of treatment in people with different types of cancer is frequent. Some risk factors have been identified, but CRCI is a complex phenomenon, with mediating factors related to cancer and treatment and moderating factors related with lifestyle and health.

IMPLICATIONS FOR CANCER SURVIVORS

This review highlights the importance of recognizing that this cognitive dysfunction is frequent, mild to moderate in nature but with great impact on quality of life.

A Hypothesis-Generating Study Using Electrophysiology to Examine Cognitive Function in Colon Cancer Patients

INTRODUCTION

The purpose of this study was to describe the trajectory of cognitive function using neuropsychological tests and electrophysiological measures in individuals receiving 5FU/oxaliplatin chemotherapy for colon cancer.

METHODS

A total of 10 participants were tested at baseline (within 3 weeks of starting chemotherapy), 6 months (coinciding with the end of chemotherapy treatment), and 12 months (approximately 6 months post-chemotherapy). Participants completed neuropsychological tests and electrophysiology recordings of P300 event-related potential (ERP) elicited by a sustained attention to response task paired with experience sampling of attentional states (subjective reports of on-task or mind wandering).

RESULTS

No change in mean neuropsychological test performance was observed. Comparison of mean P300 ERP amplitudes as a function of attentional states (on-task vs. mind wandering) revealed no main effect of attentional state observed at baseline or 6 months, but a significant effect of attention was observed at 12 months, consistent with effects observed in healthy individuals.

CONCLUSIONS

Future studies can consider sustained attention constructs when studying cognitive function in colon cancer patients.

Cognitive impairment after cytotoxic chemotherapy

Background

Neurotoxicity is a frequent side effect of cytotoxic chemotherapy and affects a large number of patients. Despite the high medical need, few research efforts have addressed the impact of cytotoxic agents on cognition (ie, postchemotherapy cognitive impairment; PCCI). One unsolved question is whether individual cytotoxic drugs have differential effects on cognition. We thus examine the current state of research regarding PCCI. Neurological symptoms after targeted therapies and immunotherapies are not part of this review.

Methods

A literature search was conducted in the PubMed database, and 1215 articles were reviewed for predefined inclusion and exclusion criteria. Thirty articles were included in the systematic review.

Results

Twenty-five of the included studies report significant cognitive impairment. Of these, 21 studies investigated patients with breast cancer. Patients mainly received combinations of 5-fluorouracil, epirubicin, cyclophosphamide, doxorubicin, and taxanes (FEC/FEC-T). Five studies found no significant cognitive impairment in chemotherapy patients. Of these, 2 studies investigated patients with colon cancer receiving 5-fluorouracil and oxaliplatin (FOLFOX). Independent risk factors for PCCI were patient age, mood alterations, cognitive reserve, and the presence of apolipoprotein E e4 alleles.

Conclusions

There is evidence that certain chemotherapy regimens cause PCCI more frequently than others as evidenced by 21 out of 23 studies in breast cancer patients (mainly FEC-T), whereas 2 out of 3 studies with colon cancer patients (FOLFOX) did not observe significant changes. Further studies are needed defining patient cohorts by treatment protocol in addition to cancer type to elucidate the effects of individual cytotoxic drugs on cognitive functions.

Cognitive Functioning and Psychological Well-being in Breast Cancer Patients on Endocrine Therapy

BACKGROUND/AIM

Anti-cancer therapies may deteriorate cognitive functioning, affective functioning and psychological well-being.

MATERIALS AND METHODS

In this prospective longitudinal pilot study, premenopausal and postmenopausal patients received adjuvant endocrine therapy (ET) (tamoxifen with or without LHRH analog or aromatase inhibitor) or were observed only (control group). At baseline testing and 6, 12 and 24 months thereafter, cognitive, depression and anxiety tests and quality of life (QOL) measurements were performed.

RESULTS

Overall, 46 cases were evaluated. None of the studied cognitive parameters differed between the subgroups or changed by time. No differences were found regarding anxiety, depression or QOL measures either. Baseline cognitive test and QOL results were in association with later anxiety and depression.

CONCLUSION

No cognitive impairment was found during the two years of ET. Baseline cognitive scores and QOL dimensions proved good predictors of later anxiety and depression.

Cognitive impairment following chemotherapy for breast cancer: The impact of practice effect on results

Chemotherapy-Related Cognitive Impairment (CRCI) can be an adverse effect in women treated for breast cancer. Some longitudinal studies reported deficits in attention, memory, and executive function following treatment, but other studies did not find cognitive changes. It is known that practice effects (PE) on repeated assessments with cognitive tests contribute to the discrepancies in these results, but its influence on scores has not been systematically explored. The present study examines the impact of PE on retest scores in a group of women with breast cancer treated with chemotherapy and evaluated longitudinally.

METHOD

51 women with breast cancer treated with a combination of 5-fluorouracil, epirubicin, and cyclophosphamide with or without taxanes were assessed after surgery but before chemotherapy (T1), post-chemotherapy (T2), and at one year after T2 (T3). Longitudinal changes on cognitive performance were analyzed twice: when retest scores were not corrected for PE and when correction for PE was applied to T2 and T3 scores.

RESULTS

When PE was not corrected, progressive improvement over time in measures of memory and divided attention at T2 and T3 was observed. In contrast, when PE was corrected, worsening was found in measures of memory, fluency, executive function, and attention at T2 and in attention and executive function at T3. Results after correction for PE are in line with previous longitudinal studies that report cognitive impairment after treatment with chemotherapy for breast cancer.

CONCLUSION

Accounting for PE is recommended to identify true change on cognition through treatment with chemotherapy for breast cancer.

Distinct attentional function profiles in older adults receiving cancer chemotherapy

PURPOSE

While attentional function is an extremely important patient outcome for older adults, research on changes in function in this group is extremely limited. The purposes of this study were to: identify subgroups of older patients (i.e., latent growth classes) based on changes in their level of self-reported attentional function; determine which demographic and clinical characteristics were associated with subgroup membership; and determine if these subgroups differed on quality of life (QOL) outcomes.

METHODS

Older oncology outpatients (n = 365) who were assessed for changes in attention and working memory using the Attentional Function Index a total of six times over two cycles of chemotherapy (CTX). QOL was assessed using the Medical Outcomes Study-Short Form 12 and the QOL-Patient Version Scale. Latent profile analysis (LPA) was used to identify subgroups of older adults with distinct attentional function profiles.

RESULTS

Three distinct attentional functional profiles were identified (i.e., low, moderate, and high attentional function). Compared to the high class, older adults in the low and moderate attentional function classes had lower functional status scores, a worse comorbidity profile and were more likely to be diagnosed with depression. In addition, QOL scores followed an expected pattern (low class < moderate class < high attentional function class).

CONCLUSIONS

Three distinct attentional function profiles were identified among a relatively large sample of older adults undergoing CTX. The phenotypic characteristics associated with membership in the low and moderate latent classes can be used by clinicians to identify high risk patients.

The Role of Oxidative Stress in Etiopathogenesis of Chemotherapy Induced Cognitive Impairment (CICI)-"Chemobrain"

Chemobrain or chemotherapy induced cognitive impairment (CICI) represents a new clinical syndrome characterised by memory, learning and motor function impairment. As numerous patients with cancer are long-term survivors, CICI represent a significant factor which may interfere with their quality of life. However, this entity CICI must be distinguished from other cognitive syndromes and addressed accordingly. At the present time, experimental and clinical research suggests that CICI could be induced by numerous factors including oxidative stress. This type of CNS injury has been previously described in cancer patients treated with common anti-neoplastic drugs such as doxorubicine, carmustine, methotrexate and cyclophosphamide. It seems that all these pharmacological factors promote neuronal death through a final common pathway represented by TNF alpha (tumour necrosis factor). However, as cancer in general is diagnosed more commonly in the aging population, the elderly oncological patient must be treated with great care since aging per se is also impacted by oxidative stress and potentiually by TNF alpha deleterious action on brain parenchyma. In this context, some patients may develop cognitive dysfunction well before the appearance of CICI. In addition, chemotherapy may worsen their cognitive function. Therefore, at the present time, there is an acute need for development of effective therapeutic methods to prevent CICI as well as new methods of early CICI diagnosis.

Examining the effects of adjuvant chemotherapy on cognition and the impact of any cognitive impairment on quality of life in colorectal cancer patients: study protocol

BACKGROUND

Research suggests that chemotherapy can cause deficits in both patients' objectively measured and self-reported cognitive abilities which can in turn affect their quality of life (QoL). The majority of research studies have used post-treatment retrospective designs or have not included a control group in prospective cohorts. This has limited the conclusions that can be drawn from the results. There have also been a disproportionate number of studies focussed on women with breast cancer, which has limited the generalisability of the results to other cancer populations.

AIM

This study aims to identify the extent and impact of chemotherapy-induced cognitive decline in colorectal cancer patients. Possible associations with poorer QoL will also be explored.

DESIGN

This will be a longitudinal controlled cohort study. Questionnaires measuring subjective cognitive functioning, QoL, fatigue and mood, and neuropsychological assessments of objective cognitive function will be collected pre-, mid- and post- chemotherapy treatment from a consecutive sample of 78 colorectal cancer patients from five London NHS Trusts. A further 78 colorectal cancer surgery only patients will be assessed at equivalent time points; this will allow the researchers to compare the results of patients undergoing surgery, but not chemotherapy against those receiving both treatments. Pre- and post-chemotherapy difference scores will be calculated to detect subtle changes in cognitive function as measured by the objective neuropsychological assessments and the self-reported questionnaires. A standardised z-score will be computed for every patient on each neuropsychological test, and for each test at each time point. The post-chemotherapy score will then be subtracted from the pre-chemotherapy score to produce a relative difference score for each patient. ANCOVA will be used to compare mean difference z-scores between the chemotherapy and surgery-only groups while controlling for the effects of gender, age, depression, anxiety, fatigue and education.

DISCUSSION

The result from this study will indicate whether a decline in cognitive functioning can be attributed to chemotherapy or to disease, surgical or some other confounding factor. Identification of risk factors for cognitive deficits may be used to inform targeted interventions, in order to improve QoL and help patients' cope.

Cognitive Function in Patients With Colorectal Cancer Who Do and Do Not Receive Chemotherapy: A Prospective, Longitudinal, Controlled Study

PURPOSE

Cognitive dysfunction is reported in people with cancer. Therefore, we evaluated longitudinal changes in cognitive function and underlying mechanisms in people with colorectal cancer (CRC) and healthy controls (HCs).

PATIENTS AND METHODS

Participants completed cognitive assessments and questionnaires reporting cognitive symptoms, fatigue, quality of life, and anxiety/depression at baseline (before chemotherapy, if given) and 6, 12, and 24 months. Blood tests included cytokines, clotting factors, apolipoprotein E genotype, and sex hormones. Primary end point was overall cognitive function measured by the Global Deficit Score at 12 months.

RESULTS

We recruited 289 patients with localized CRC (173 received chemotherapy; median age, 59 years; 63% male), 73 patients with limited metastatic/recurrent CRC, and 72 HCs. Cognitive impairment was more frequent in patients with localized CRC than HCs at baseline (43% v 15%, respectively; P < .001) and 12 months (46% v 13%, respectively; P < .001), with no significant effect of chemotherapy. Attention/working memory, verbal learning/memory, and complex processing speed were most affected. Cognitive impairment was similar in patients with localized and metastatic CRC. Cytokine levels were elevated in patients with CRC compared with HCs. There was no association between overall cognitive function and fatigue, quality of life, anxiety/depression, or any blood test. Cognitive symptoms at 12 months were reported in 25% of patients with localized CRC versus 17% of HCs (P = .19). More participants who received chemotherapy had cognitive symptoms at 6 months (32%) versus those who did not (16%; P = .007), with no significant difference at 12 months (29% v 21%, respectively; P = .19). Objective cognitive function was only weakly associated with cognitive symptoms.

CONCLUSION

Patients with CRC had substantially more cognitive impairment at every assessment than HCs, with no significant added effect of chemotherapy. Mechanisms of cognitive impairment remain unknown.

Cognitive function and fatigue after diagnosis of colorectal cancer

BACKGROUND

Cognitive impairment and fatigue have been associated with cancer and its treatment. We present baseline data from a large longitudinal study that evaluates cognitive function, fatigue, and potential underlying mechanisms following diagnosis of colorectal cancer (CRC).

PATIENTS AND METHODS

We evaluated CRC patients with stage I-III disease before or after surgery, participants with limited metastatic disease and healthy controls (HC). Neuropsychological evaluation included clinical and computerised tests. Participants completed questionnaires for fatigue and quality of life (QOL)-(FACT-F), anxiety/depression, and cognitive symptoms (FACT-Cog). Ten cytokines, clotting factors, sex hormones, carcinoembryonic antigen (CEA), and apolipoprotein E genotype were evaluated. Primary end points were cognitive function on clinical tests evaluated by a Global Deficit score (GDS) and fatigue. Associations between test results, demographic, and disease related factors were explored.

RESULTS

We assessed 291 participants with early-stage disease [median age 59 (23-75) years, 63% men], 72 with metastatic disease, and 72 HC. Using GDS, 45% (126/281) of participants with early-stage CRC had cognitive impairment versus 15% (11/72) of HC (odds ratio 4.51, 95% confidence interval 2.28-8.93; P < 0.001), with complex processing speed, attention/working memory, and verbal learning efficiency being most affected. Women with early-stage CRC had greater cognitive impairment than men [55/105 (52%) versus 71/176 (40%), P < 0.050]. Cognitive symptoms were self-reported by 21% (59/286) of early-stage patients versus 17% (12/72) of HC; fatigue by 52% (149/287) of early-stage patients and 26% (19/72) of HC (P < 0.0001). Women reported more fatigue than men (P = 0.003). Fatigue, QOL, anxiety/depression, and cognitive symptoms were associated with each other (r = 0.43-0.71), but not with neuropsychological performance. Most cytokines were elevated in cancer patients. Cognitive function was not associated with cytokines, sex hormones, clotting factors, CEA, or apolipoprotein E genotype.

CONCLUSIONS

The incidence of cognitive impairment was three to five times higher in CRC patients than HC, with women having higher impairment rates than men. The cognitive impairment profile suggests dysfunction primarily in fronto-subcortical brain systems.

TRIAL REGISTRATION

NCT00188331.

Longitudinal study of cognitive dysfunctions induced by adjuvant chemotherapy in colon cancer patients

BACKGROUND

Chemotherapy can induce cognitive impairment in cancer patients. The main goal of this longitudinal study was to determine the incidence, characteristics, and duration of cognitive dysfunction in patients treated with adjuvant chemotherapy for colon cancer.

PATIENTS AND METHODS

We assessed cognitive function, quality of life, anxiety and depression, fatigue, and hemoglobin levels in colon cancer patients at three assessment points: pre-chemotherapy (n=81), post-chemotherapy (n=73), and after 6-month follow-up (n=54). All patients were treated with oxaliplatin plus 5-fluorouracil/leucovorin (FOLFOX4) for 6 months.

RESULTS

Thirty patients (37%) had cognitive impairment in the pre-chemotherapy evaluation, mainly in processing speed and psychomotor executive function (Trail Making Test A and B). At the end of treatment, the main domain affected was the verbal memory, with an acute decline detected in 56% of patients. Fifty-four percent of the patients improved their dysfunction after 6 months of follow-up, whereas 18 (33%) of them showed worsening in at least one test. Cognitive impairment was most common in older patients and in those with less years of education. Quality of life, anxiety, depression, fatigue, and hemoglobin did not influence the results of the cognitive tests.

CONCLUSIONS

Adjuvant FOLFOX4 in patients with colon cancer can have a negative effect on verbal memory. This deterioration is usually mild and transient.