Measure of Ovarian Symptoms and Treatment concerns (MOST) indexes and their associations with health-related quality of life in recurrent ovarian cancer.

PURPOSE: The Measure of Ovarian Symptoms and Treatment (MOST) concerns is a validated patient-reported symptom assessment tool for assessing symptom benefit and adverse effects of palliative chemotherapy in women with recurrent ovarian cancer (ROC). We aimed to examine (i) how symptoms within MOST symptom indexes track together (i.e. co-occur) and (ii) the association between MOST symptom indexes and key aspects of health-related quality of life (HRQL). METHOD: A prospective cohort of women with ROC completed the MOST-T35, EORTC QLQ-C30 and EORTC QLQ-OV28 at baseline and before each cycle of chemotherapy. Analyses were conducted on baseline and end-of-treatment data. Exploratory factor analysis and hierarchical cluster analysis identified groups of co-occurring symptoms. Path models examined associations between MOST symptom indexes and HRQL. RESULTS: Data from 762 women at baseline and 681 at treatment-end who completed all 22 symptom-specific MOST items and at least one HRQL measure were analysed. Four symptom clusters emerged at baseline and treatment-end: abdominal symptoms, symptoms associated with peripheral neuropathy, nausea and vomiting, and psychological symptoms. Psychological symptoms (MOST-Psych) and symptoms due to disease (ovarian cancer) or treatment (MOST-DorT) were associated with poorer scores on QLQ-C30 and OV28 functioning domains and worse overall health at both time points. CONCLUSION: Four MOST symptom clusters were consistent across statistical methods and time points. These findings suggest that routine standardized assessment of psychological and physical symptoms in clinical practice with MOST plus appropriate symptom management referral pathways is an intervention for improving HRQL that warrants further research.