When considered with other parameters, prognostic factors of survival in far advanced cancer patients are necessary to enable the doctor, the patient, and his or her relative to choose the most suitable clinical management and care setting. Original studies and literature reviews, albeit with methodologic difficulties, have identified the most important prognostic factors as being: CPS, KPS, signs and symptoms relating to nutritional status (i.e., weight loss, anorexia, dysphagia, xerostomia), other symptoms (dyspnea, cognitive failure) and some simple biologic parameters (serum albumin level, number of white blood cells and lymphocyte ratio). Some authors have weighed the different impact of the most important prognostic factors and have integrated them into prognostic scores for clinical use. Despite the usefulness of these instruments, however, the communication of a poor prognosis is one of the most difficult moments to face in the relationship between doctor and patient.