Increased survival time or better quality of life? Trade-off between benefits and adverse events in the systemic treatment of cancer.

Abstract

Primary objective of the study was to assess the relative weighting between benefit in survival time (SV), benefit in quality of life (QoL) and willingness to experience adverse events (AEs), in patient preferences for chemotherapy treatment. We included cancer patients with current or past systemic treatment of cancer (STC) as well as physicians placed as hypothetical patients. Participants filled a choice-based conjoint analysis questionnaire with 19 choices among three STC scenarios with variable amounts of benefit in SV or QoL and different types AEs. One hundred patients (50 on curative and 50 on palliative intention treatment) and 114 physicians (61 oncologists and 53 non-oncologists) were included and asked about their preferred chemotherapy treatment. The relative weighting (sum 100%) of SV-QoL-AEs for making the choice in the 100 patients was SV35%-CV33%-AEs31% what was not significantly different from a random distribution (Goodness of fit Chi square P = 0.91) just as it was not for both subgroups, palliative (SV37%-QoL29%-AEs34%; GoF Chi square P = 0.55) and curative (SV34%-QoL36%-AEs30%; GoF Chi square P = 0.73) treatment. The observed distribution in the group of 114 physicians (SV46%-QoL31%-AEs23%) was significantly different from a random distribution (GoF Chi square P = 0.018) just as it was for both subgroups, medical oncologists (SV48%-QoL29%-AEs23%; GoF Chi square P = 0.006) and non-medical oncologists (SV44%-QoL33%-AEs23%; GoF Chi square P = 0.04). The three attributes (SV, QoL, and AEs) are considered in the same way by cancer patients to make choices on their STC. On the contrary, when placed as hypothetical patients, physicians prefer for themselves those treatments that provide more SV.