Cancer cachexia syndrome (CCS) is frequent, causing high morbidity and mortality in affected ones. The mechanism is catabolism caused by the tumour. CRP is a surrogate marker for catabolism. There are no effective treatment options against CCS. Lenalidomide, a derivate of thalidomide, is an immunomodulatory drug (IMiD®). One of its' main effect is a decrease in inflammatory cytokines. As CCS treatment, thalidomide has shown in a randomized controlled trial to stabilize lean body mass. The effect of lenalidomide in solid tumour patients was negligible although, there might be a decrease in tumour progression. However, even if lenalidomide may be uninteresting as an anticancer treatment it might affect CCS dynamics. Respective data are currently lacking. Therefore, a dose level where an anticancer effect could be expected was chosen (group A). Relevant anti-inflammatory effect may occur below the commonly used doses to achieve tumour control, which is expected to be the main anti-cachexia effect. Therefore, a second CRP-response guided treatment arm (group B) was chosen.