BackgroundRates of psychiatric conditions common to end-stage cancer patients (delirium, depression, anxiety disorders) remain unchanged. However, patient numbers have increased as the population has aged; indeed, cancer is a chief cause of mortality and morbidity in older populations. Effectiveness of psychiatric interventions and research to evaluate, inform, and improve interventions is critical to these patients’ care. This article’s intent is to report results from a recent review study on the effectiveness of interventions for psychiatric conditions common to end-stage cancer patients; the review study assessed the state of research regarding treatment effectiveness. Unlike previous review studies, this one included non-traditional/alternative therapies and spirituality interventions that have undergone scientific inquiry.MethodsA five-phase systematic strategy and a theoretic grounded iterative methodology were used to identify studies for inclusion and to craft an integrated, synthesized, comprehensive, and reasonably current end-product.ResultsPsychiatric medication therapies undoubtedly are the most powerful treatments. Among them, the most effective (i.e., “best practices benchmarks”) are: (1) for delirium, typical antipsychotics—though there is no difference between typical vs. atypical and other antipsychotics, except for different side-effect profiles, (2) for depression, if patient life expectancy is ≥4–6 weeks, then a selective serotonin reuptake inhibitor (SSRI), and if < 3 weeks, then psychostimulants or ketamine, and these generally are useful anytime in the cancer disease course, and (3) for anxiety disorders, bio-diazepams (BDZs) are most used and most effective. A universal consensus suggests that psychosocial (i.e., talk) therapy and spirituality interventions fortify the therapeutic alliance and psychiatric medication protocols. However, trial studies have had mixed results regarding effectiveness in reducing psychiatric symptoms, even for touted psychotherapies.ConclusionsThis study’s findings prompted a testable linear conceptual model of co-factors and their importance for providing effective psychiatric care for end-stage cancer patients. The complicated and tricky part is negotiating patients’ diagnoses while articulating internal intricacies within and between each of the model’s co-factors. There is a relative absence of scientifically derived information and need for more large-scale, diverse scientific inquiry. Thus, this article is an impassioned plea for accelerated study and better care for end-stage cancer patients’ psychiatric conditions.