Psychological Distress and Quality of Life in Patients with Colon Cancer: Predictors, Moderating Effects, and Longitudinal Impact

<b>Background/Objectives</b>: Psychological distress, including anxiety and depression, significantly impacts quality of life (QoL) in colorectal cancer patients. This study explores the relationship between psychological distress and QoL, identifies risk factors (e.g., advanced disease stage, socioeconomic status, and social support levels), and evaluates the influence of emotional and social functioning on patient well-being. Additionally, this study examines workplace reintegration challenges faced by cancer survivors. <b>Methods</b>: A longitudinal study was conducted with 50 patients diagnosed with colorectal cancer undergoing chemotherapy. QoL was assessed using the EORTC QLQ-C30 and EQ-5D scales, while anxiety and depression were measured using the Hospital Anxiety and De-pression Scale (HADS). Assessments were conducted at baseline and at the end of a six-month treatment period. Data were analyzed using correlation and multivariate regression analyses to explore associations between psychological distress and QoL, adjusting for disease stage, social support, and demographic factors. <b>Results</b>: Emotional functioning showed a statistically significant improvement by the sixth chemotherapy cycle (<i>p</i> < 0.05), while physical and role functions remained stable. However, psychological health, as assessed through HADS, showed no significant improvement, highlighting the need for targeted psychological support. Negative correlations were observed between QoL scores and anxiety and depression levels, with stronger associations detected in the later stages of treatment. Patients with advanced disease stages and poor social support were identified as high-risk groups for psychological distress. Effect sizes (Cohen's d) and confidence intervals were calculated to assess the practical significance of findings. <b>Conclusions</b>: This study highlights the critical impact of psychological distress on the QoL of colorectal cancer patients, emphasizing the importance of integrating systematic psychological assessments and tailored interventions in oncology care. Future research should incorporate larger sample sizes, extended follow-up periods, and an exploration of mediating factors to enhance understanding and improve patient-centered interventions.