The present study was aimed at assessing quality of life (QoL) in a total of 450 melanoma patients who filled out the EORTC QLQ-C30 (Q1; 15 months post diagnosis) as part of the OVIS Study. Follow-up questionnaires (Q2) were administered two years after Q1. The analyses presented herein were based on the following assumptions: QoL of melanoma patients is worse than that of a German reference population. Further, both tumor location and tumor stage have an influence on self-reported QoL, with patients with tumors located on face, head, neck, and advanced tumor stage (T3/T4) reporting the worst QoL levels. Finally, patients’ QoL improves over time based on the theory of disease adaptation. In contrast to the above assumptions, with the exception of global health/QoL scores, differences between OVIS and the reference population were below the minimal clinical important difference of ten points. Furthermore, no clinically meaningful differences were found between patients after stratifying our data by tumor location and tumor stage. Finally, no clinically relevant changes were seen between Q1 and Q2 across all scales of the EORTC QLQ-C30. However, when data were stratified by patients with stable disease versus those with progression, clinically relevant differences were found between Q1 and Q2 predominantly in women in the latter group regarding emotional function, insomnia, dyspnoea, and fatigue. The lack of clinically meaningful differences across strata (tumor location; tumor stage), time, and patients compared to a reference population is surprising. However, it is possible that the instrument used, a generic QoL instrument, is generally not sensitive enough to detect differences in melanoma patients. Our findings may further be explained by the fact that all patients included in our sample had been diagnosed well before Q1, i.e.
, main illness adaptation processes may have occurred before study entry.