Cancer-Related Cognitive Dysfunction: A Narrative Review for Clinical Practice

BACKGROUND

Cancer-related cognitive dysfunction (CRCD) is a major functional disorder in patients with cancer. This central nervous dysfunction is found in up to 60% of patients after tumour therapy, often significantly limits the quality of life, and significantly impedes participation in working life. For this reason, diagnosis and treatment of CRCD are of central importance. This narrative review is intended to provide an overview and support for practical clinical care with regard to diagnostics and therapeutic options.

SUMMARY

In Germany, CRCD has received insufficient attention in clinical practice due to the lack of guidelines for diagnosis and therapy. The pathophysiology is complex and cannot be explained by chemotherapeutic treatment alone. In addition to the tumour disease as such and the tumour therapy, psychological factors such as anxiety and depression as well as sleep disorders also play a significant role. Today, it is known that in addition to age, molecular genetic changes also have an effect on cognitive function. Morphologically, CRCD can be located in the frontal cortex and hippocampus. In addition to easy-to-use screening instruments such as the visual analogue scale, validated questionnaires such as the Questionnaire of Subjectively Experienced Deficits in Attention (FEDA) developed in Germany are also available. These allow the suspected diagnosis to be substantiated and the patient to be referred to further neurological, neuropsychological, or psycho-oncological diagnostics. Within the framework of further neuropsychological diagnostics, the International Cognition and Cancer Task Force (ICCTF) recommends testing learning, memory, processing speed, and executive functions. From the authors' point of view, a step-by-step diagnosis is recommended in order to avoid overdiagnosis. In clinical practice, graduation according to the "Common Terminology Criteria for Adversity Events" (CTCAE Version 5.0) is suitable for assessing the degree of severity. Cognitive training should be behaviourally oriented and include regular practice of cognitive skills to restore attention, psychomotor speed, memory, and executive functions. The best evidence is currently found for web-based training programmes that can be used by the patient at home. There is also evidence for mindfulness training and physical exercises. In particular, the combination of these three therapeutic elements currently seems to be the optimal treatment strategy for CRCD.

KEY MESSAGES

Cognitive dysfunction should be given much more attention in the clinical care of cancer patients. Diagnostic tools for this purpose and evidence-based therapeutic interventions are available. In the future, networks should be created that allow for better care of patients with CRCD.

The congruency of neuropsychological and F18-FDG brain PET/CT diagnostics of Alzheimer's Disease (AD) in routine clinical practice: insights from a mixed neurological patient cohort

Background

Diagnostics of Alzheimer’s Disease (AD) require a multimodal approach. Neuropsychologists examine the degree and etiology of dementia syndromes and results are combined with those of cerebrospinal fluid markers and imaging data. In the diagnostic process, neuropsychologists often rely on anamnestic and clinical information, as well as cognitive tests, prior to the availability of exhaustive etiological information. The congruency of this phenomenological approach with results from FDG-PET/CT examinations remains to be explored. The latter yield highly accurate diagnostic information.

Method

A mixed sample of N = 127 hospitalized neurological patients suspected of displaying a dementia syndrome underwent extensive neuropsychological and FDG-PET/CT examinations. Neuropsychological examinations included an anamnestic and clinical interview, and the CERAD cognitive test battery. Two decisional approaches were considered: First, routine diagnostic results were obtained, i.e. the final clinical decision of the examining neuropsychologist (AD_Clinical vs. non-AD_Clinical). Secondly, a logistic regression model was implemented, relying on CERAD profiles alone. CERAD subscales that best predicted AD based on FDG-PET/CT were identified and a nominal categorization obtained (AD_Test vs. non-AD_Test). Congruency of results from both approaches with those of the FDG-PET/CT (AD_PET vs. non-AD_PET) were estimated with Cohen’s Kappa (κ) and Yule’s Y coefficient of colligation. Descriptive estimates of accuracy, sensitivity and specificity of CERAD relative to FDG-PET/CT diagnostics were derived.

Results

AD_PET patients constituted N = 33/127 (26%) of the sample. The clinical decision approach (AD_Clinical vs. non-AD_Clinical) showed substantial agreement with the FDG-PET/CT classification (κ = .69, Y = .72) involving good accuracy (84.2%), moderate sensitivity (75.8%) and excellent specificity (92.6%). In contrast, the decisional approach that relied on CERAD data alone (AD_Test vs. non-AD_Test) involved only moderate agreement with the FDG-PET/CT (κ = .54, Y = .62) with lower accuracy (74.8%), attributable to decreased sensitivity (56.3%) and comparable specificity (93.3%).

Conclusions

It is feasible to identify AD through a comprehensive neuropsychological examination in a mixed sample of neurological patients. However, within the boundaries of methods applied here, decisions based on cognitive test results alone appear limited. One may conclude that the clinical impression based on anamnestic and clinical information obtained by the neuropsychological examiner plays a crucial role in the identification of AD patients in routine clinical practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02614-4.

[Collation of word retrieval disorders in patients with Alzheimer's dementia]

BACKGROUND

One of the first symptoms of Alzheimer's disease (AD) is word retrieval deficits. A systematic evaluation of word retrieval deficits can have an important predictive value for developing Alzheimer's disease.

OBJECTIVE

Is the test for finding word retrieval deficits (word finding = WoFi) able to detect deficits in word retrieval and does it correlate with other dementia tests?

METHODS

A word retrieval test called WoFi was developed. It is an instrument that tests word retrieval deficits based on 50 questions. A maximum of 100 points can be scored.

RESULTS

The control group scored significantly better than the AD group. Using a cut-off score of 84 points WoFi could discriminate controls from subjects with a sensitivity of 95% and a specificity of 92%.

CONCLUSION

The use of WoFi was able to test for word retrieval deficits. Application required less than 15 min and test instructions are very simple. This instrument might be useful in telehealth.