Managing patients with brain tumors can involve behavioral and psychiatric phenomena, occurring at different time points. Review of the literature. Five causes were identified. 1. Focal and diffuse brain damage by the tumor Symptoms of anger, loss of emotional control, indifference and changes in behavior and personality appear. The extent to which tumor location impacts on psychopathology is not clear. Clinically, also apathy and loss of executive function can occur. In lesions of the paralimbic structures mood swings are dominant. Neuropsychological symptoms are related to focal pathology. 2. Psychiatric causes Manifestations can present as anxiety, depression, mania and psychosis. Few recent publications are available. It is useful to make a distinction between a,,psychiatric reaction (towards the disease)” and an organic psychosis. 3. Influence of seizures on behavior Brain tumors are one of the main causes of acquired epilepsies and are associated with 3–6% of all new cases of epilepsy. Rapidly growing tumors, as glioblastomas (GBM), are frequently associated with seizures. In patients with primary brain tumors with epilepsy cognitive impairment, abnormal scores in the anxiety scale and depression were noted. Brain tumors can cause status epilepticus, including the non-convulsive type. 4. Tumor treatment Treatment-induced effects may occur at any stage of the disease. Radiation can induce acute, or delayed effects, which are important in low grade glioma (LGG), and less frequent in GBM. Steroids can have psychotropic effects, ranging from unspecific excitatory state, towards psychosis and depression. Also, rapid discontinuation of prolonged steroid therapy causes mood swings. The issue of “chemobrain” has been attracting attention in the treatment of LGG. The clinical correlation is slowing of mentation and cognition and is also termed,,chemofog”. Most antineoplastic drugs used for the treatment of GBM, as temozolomide (TMZ) do not have psychotropic effects. Older drugs as procarbazine can cause psychiatric symptoms. VEGF inhibitors, can induce “posterior reversible encephalopathy syndrome” resulting in mental changes. Benzodiazepines, antidepressants and rarely anti-dementia drugs can cumulate and cause delirium as well as anticonvulsants. 5. Overlap of several causes Practically, often several causes can overlap. The identification of the most prevalent cause is important, followed by symptomatic therapy. Psychiatric alterations can be part of the management of patients with brain tumors. Symptom-oriented treatment of psychiatric manifestations, including psychotherapy, drug treatment and individual care is warranted. Communication with patients, caregivers and the involved health care professionals is essential.

The far-reaching meaning of placebo and nocebo are often undervalued or ignored in clinical practice. Presently the term placebo is either used: (1) in the context of randomized controlled trials, (2) to describe a sham treatment in various nuances, (3) to describe effects often attributed to healers. This diverges from "no treatment" which has entirely different implications. Even less accepted is the term nocebo, which literally means "will harm". As placebo this term can be ambiguous and can appear in many concealed ways. Research in the past years has been based on experiments and elaborated studies and on imaging studies. This both placebo and nocebo also have an empirical and scientific background. Also, ethical aspects concern placebo and nocebo issues, in particular in regard to changing relations of the physician-patient relationship, which affects both terms. Based on this knowledge, increasingly physicians and patients are aware of these phenomena, and it will be important to raise awareness not only in physicians, but also the health care personal involved in the treatment of patients.