[Apathy or depression? Do you have a nose for it? Four case reports of paramedian frontal tumors].

We report four cases of patients with clinically isolated apathy which was mistaken for depression even though they were suffering from voluminous brain tumors. These cases remind us that rigorous clinical analysis is essential: searching for signs of organic origin or psychiatric etiology is fundamental to avoid an incorrect diagnosis. In particular, these four patients displayed anosmia, an uncommon symptom for patients suffering from depression. In addition, brain imaging is important to correctly identify the most prudent medical and/or surgical management strategy. In this short discussion, we propose an algorithm for the clinical diagnosis of apathy.