Introduction
Pelvic exenteration (PE) is a treatment option for advanced primary or locally recurrent cancers, involving the partial or complete removal of organs in the pelvis, posing high-risk of psychological distress post-surgery. The Distress Thermometer (DT) is a practical, single-item tool to screen for distress. This study examined the convergent validity, responsiveness, and optimal cutoff points of the DT in patients receiving PE to inform clinical practice.
Methods
A secondary analysis was conducted using cohort study data collected from adult patients who underwent PE at a quaternary referral hospital. The Emotional Wellbeing (EWB) subscale of the FACT-G was used as an external criterion to examine responsiveness. Receiver Operating Characteristic curve analysis assessed whether the DT adequately distinguished those with worsened emotional well-being. Correlation coefficient analysis was performed between the item "I feel nervous" and the DT score to assess Convergent validity. To determine the optimal cutoff score, the following indices were evaluated using the existing EWB cutoff: sensitivity, specificity, positive/negative predictive values, and Clinical Utility Index (CUI).
Results
377 patients were included in the analyses (mean age:61 years, 56% male; 41% recurrent rectal cancer). Responsiveness was demonstrated through the Area Under the Curve of 0.72 for distinguishing those with worsened emotional well-being from baseline to post-6 months. Convergent validity was demonstrated through a moderately positive correlation between the DT score and the item "I feel nervous" (rs=0.48, P<.001, n=370) as predicted. Data supported an optimal cutoff DT score of 4.5 against EWB: Sensitivity; 81.5%, Specificity; 58.4%, CUI+value; 0.32 (poor utility for case finding), CUI- value; 0.53 (satisfactory utility for ruling out cases).
Conclusions
The DT is an appropriate screening tool for monitoring psychological distress after PE. However, the high false-positive rate indicates that this tool should not be used as a diagnostic tool.