Therapy with Immune Checkpoint Inhibitors for Solid Tumors in Patients with Preexisting Systemic Autoimmune Diseases

Background: Patients with systemic autoimmune diseases (SAID) are at a higher risk of developing neoplasms, such as solid tumors and hematologic malignancies. Chronic stimulation of the immune system and some treatments for these diseases increase the risk of developing solid tumors. Also, it is known that patients with SAID are usually excluded from clinical trials, but immune checkpoint inhibitors (ICI) are still used in these patients in everyday practice. Objectives: The objective of this article is to review the most up-to-date and robust literature on the use of ICI in patients with SAID for the treatment of solid tumors to obtain information on the efficacy and safety of these drugs in this subgroup of patients. Methods: A literature review was performed through international databases that included PubMed, Medline, Scopus, and Google Scholar. Articles about the use of ICI for solid tumors in patients with SAID were included; the types of articles included were retrospective studies, systematic reviews, and meta-analyses. A summarized descriptive analysis was performed about the efficacy and safety of ICI treatment for the main solid tumors (lung, melanoma, and other cutaneous malignancies, as well as renal and urothelial carcinoma). Conclusions: In general, it seems that ICI treatment is safe in patients with asymptomatic SAID. Close follow-up with a multidisciplinary team should be performed when ICI therapy is prescribed. A substitution of selective immunosuppressants (SIM) in place of nonselective immunosuppressants (NSIM) in asymptomatic patients is recommended before the initiation of ICI.