<qa>  What is the current effective drug in anti-depression clinical therapy?Major depression prevail in patients with malignant tumor with an incident rate of 20 - 40, 2-3 times more than the prevalence of population, especially high in patients with advanced solid tumor patients as 40 - 50.6. National Comprehensive Cancer Network NCCN palliative care guideline recommended PHQ-9 as the diagnosis tool for depression, total scores 8 was considered the standard of malignant tumor related depression. Major depression had been proved related with malignant tumors, mirtazapine is the currently effective drug in anti-depression clinical therapy, have better tolerance and equal effect compared to Tricyclic antidepressants TCAs and 5-hydroxytryptamine 5-HT or noradrenaline serotonin-norepinephrine reuptake inhibitors NE-SNRIs. 