Selected complications in neuro-oncology patients

The neural basis of temporal preparation: Insights from brain tumor patients

When foreperiods (FPs) of different duration vary on a trial-by-trial basis equiprobably but randomly, the RT is faster as the FP increases (variable FP effect), and becomes slower as the FP on the preceding trial gets longer (sequential effects). It is unclear whether the two effects are due to a common mechanism or to two different ones. Patients with lesions on the right lateral prefrontal cortex do not show the typical FP effect, suggesting a deficit in monitoring the FP adequately [Stuss, D. T., Alexander, M. P., Shallice, T., Picton, T. W., Binns, M. A., Macdonald, R., et al. (2005). Multiple frontal systems controlling response speed. Neuropsychologia, 43, 396-417]. The aim of this study was two-fold: (1) to replicate this neuropsychological result testing cerebral tumor patients before and after surgical removal of the tumor located unilaterally in the prefrontal, premotor or parietal cortex, respectively and (2) to investigate whether the sequential effects would change together with the FP effect (supporting single-process accounts) or the two effects can be dissociated across tumor locations (suggesting dual-process views). The results of an experiment with a variable FP paradigm show a significant reduction of the FP effect selectively after excision of tumors on right prefrontal cortex. On the other hand, the sequential effects were reliably reduced especially after surgical removal of tumors located in the left premotor region, despite a normal FP effect. The latter dissociation between the two effects supports a dual-process account of the variable FP phenomena. This study demonstrates that testing acute cerebral tumor patients represents a viable neuropsychological approach for the fractionation and localisation of cognitive processes.

Managing symptoms and side effects during brain tumor illness

Malignant brain tumors and the therapies used to treat them can present challenging problems. Headache is the most common symptom during brain tumor illness. Etiology determines the exact management approach, but pharmacologic and non pharmacologic measures may be used. Seizures also commonly occur and are best managed with anti epileptic drug therapy. Infection and deep venous thrombosis are concerns and are best approached by preventive measures and early aggressive intervention if those measures fail. Depression, fatigue, memory and personality changes may complicate care and are approached on an individual basis. Early discussion about end-of-life issues is necessary because the disease itself can impair decision-making ability.

Validation of the M.D. Anderson Symptom Inventory Brain Tumor Module (MDASI-BT)

BACKGROUND

Symptom occurrence has been shown to predict treatment course and survival in patients with solid tumors. Primary brain tumor (PBT) patients are unique in the occurrence of neurologic symptoms. Currently, no instrument exists that measures both neurologic and cancer-related symptoms.

METHODS

Patients diagnosed with PBT participated in this study. Data was collected at one point in time and included demographic and clinical factors, and the M.D. Anderson Symptom Inventory-Brain Tumor Module (MDASI-BT). The study evaluated the reliability and validity of the MDASI-BT in primary brain tumor patients.

RESULTS

Two hundred and one patients participated in this study. Mean symptom severity of items as well as cluster analysis was used to reduce the number of total items to 22 (13 core, 9 brain tumor items). Regression analysis showed more than half (56%) of the variability in symptom severity was explained by brain module items. The MDASI-BT measures six underlying constructs including affective, cognitive, focal neurologic deficit, constitutional, generalized symptom, and a gastrointestinal related factor. The internal consistency (reliability) of the instrument was 0.91. The MDASI-BT was sensitive to disease severity based on performance status (P<0.001), tumor recurrence (P<0.01), and mean symptom interference (P<0.001).

CONCLUSIONS

The 22 item MDASI-BT demonstrated validity and reliability in patients with PBT. This instrument can be used to identify symptom occurrence throughout the disease trajectory and to evaluate interventions designed for symptom management.

Content validity of self-report measurement instruments: an illustration from the development of the Brain Tumor Module of the M.D. Anderson Symptom Inventory

PURPOSE/OBJECTIVES

To illustrate one technique for establishing content validity of measurements using the initial development and testing of the M.D. Anderson Symptom Inventory Brain Tumor Module.

DATA SOURCES

Published articles, book chapters, and subjective judgments of experts.

DATA SYNTHESIS

Content validity is the essential first step in the development of items to be included in a measurement instrument. Content validity is a criterion-referenced process that is judged by how well each item in a newly developed instrument reflects its respective objective or content domain. The stages in addressing content validity include a developmental stage and a judgment-quantification stage. Steps involved in the developmental stage include domain identification, item generation, and instrument formation. The judgment-quantification stage is when experts review the items and either report validity of the items subjectively or with an empirically referenced method, such as calculation of the content validity index. The content validity of a set of questions designed to measure symptoms in a population of patients with primary brain tumors was ascertained by using the calculation of the content validity index.

CONCLUSIONS

The final version of the M.D. Anderson Symptom Inventory Brain Tumor Module consists of the 13 core items and 18 additional items designated as valid by a panel of experts. The instrument will be administered to a group of patients to determine construct validity and reliability of the items.

IMPLICATIONS FOR NURSING

Self-report instruments are used to measure various health outcomes in oncology. Oncology nurses are in a key position to develop such instruments to be used in clinical care and research of symptoms associated with cancer. Understanding the process of content validation is an essential first step in developing new instruments.