Sarcoidosis-like reactions in cancer patients treated with immune checkpoint inhibitors: experience in a Spanish hospital

Background Immune checkpoint inhibitors (ICI) have been associated with several immune-related adverse events, including sarcoidosis-like reactions (SLR). SLR, which has a low prevalence but an increasing incidence, is similar to sarcoidosis in terms of histology, and clinical and radiological manifestations. The most commonly affected organs are hilar and mediastinal lymph nodes and skin. SLR is an exclusion diagnosis, so a lymph node biopsy can be useful to distinguish between tumor progression and SLR, particularly in tumors in which nodal involvement is very common. Patients and methods We performed a retrospective analysis of SLR in all cancer patients receiving ICIs in our institution between January 2016 and June 2020. Results Among the 1063 treated patients, seven experienced SLR, four of whom were symptomatic (cough, skin lesions, arthralgia), with time to onset ranging from 1.5 to 6.7 months after ICI initiation. All seven patients had bilateral hilar lymphadenopathy, and granulomatous reactions in five of the six patients with lymph node biopsies. SLR improved in all patients, including four patients who continued with ICI. Three patients received corticosteroids and/or stopped ICI therapy. Four of these patients had partial responses at the time SLR was identified. Conclusion Management of SLR lacks a consensus recommendation, although corticosteroids and/or stopping the ICI are generally implemented. The potential consequences of stopping anticancer treatment should be taken into consideration, particularly in the absence of clear management recommendations.