Does palliative chemotherapy really palliate and are we measuring it correctly? A mixed methods longitudinal study of health related quality of life in advanced soft tissue sarcoma

Objective Soft tissue sarcoma (STS) is a rare cancer type that when locally advanced or metastatic, is predominantly treated with palliative chemotherapy with the aim of improving both quantity and quality of life. Given modest survival data after commencing first line chemotherapy, this study examines (i) what constitutes health related quality of life (HRQoL), (ii) whether the most commonly used HRQoL assessment tool measures this and (iii) to what extent HRQoL, and its components, change during and after treatment. Design Mixed-methods longitudinal study of 66 sarcoma patients living with STS (42 commencing chemotherapy, 24 under surveillance after completing chemotherapy) involving serial EORTC QLQ-C30 questionnaires and nested-qualitative semi-structured interviews with a sub-sample of participants. EORTC QLQ-C30 score change from baseline to primary evaluation point was examined using a paired t-test. Interviews were analysed using the framework approach before both datasets were integrated. Results Five main factors, including control of pain, were identified by study participants as important components of HRQoL; these are examined within the EORTC QLQ-C30. However, others e.g. independence loss and common causes of anxiety, are not. Whilst social and psychological domains are addressed by the EORTC QLQ-C30, the quantitative change over time did reflect qualitative descriptions of decline. The mean overall EORTC QLQ-C30 HRQoL score deteriorated from baseline (60.4) to the primary evaluation point (50.2) [change of -10.2, t-test: -2.70, p = 0.01] for those receiving chemotherapy; this was in concordance with patients’ qualitative accounts. Baseline overall HRQoL scores were higher in the surveillance group suggesting a correlation with chemotherapy response and longer-term improvement in HRQoL. The evidence from both HRQoL scores and qualitative accounts indicated that the presence and control of physical symptoms were particularly important in maintaining HRQoL. Whilst fatigue deteriorated on chemotherapy (baseline 41.7 to 52.8; change of +11.1, t-test +2.51, p<0.05), pain (baseline 41.5 to 32.1; change -9.4, t-test -2.06 p<0.05) and sleep disturbance (43.1 to 28.5; change -14.6, t-test –3.05, p<0.05) both improved. Conclusion A key finding was that the EORTC QLQ-C30 assesses some but not all of the patient-reported components of HRQoL in sarcoma patients highlighting the need for either STS specific modules within the EORTC QLQ-C30 or a completely new STS specific HRQoL tool. First line palliative chemotherapy improves specific symptoms known to be prevalent and to influence HRQoL in this patient group which in some patients may translate to sustained improvement in HRQoL: further exploration and validation of these findings in larger prospective studies are warranted.