Immune-related adverse events in patients with solid-organ tumours treated with immunotherapy: a 3-year study of 102...

Immune checkpoint blockade therapy (ICBT) increases the anti-tumoural function of the immune system, but it can also induce immune-related adverse events (irAEs). Our aim was to assess the irAEs due to ICBT in patients from a single centre of Northern Spain.

We set up an observational study of patients treated in monotherapy with ICBT targeted against cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death 1 (PD-1) or its ligand (PD-L1) for solid organ tumours. All patients were followed up in a single University Hospital from March 2015 to September 2018.

We studied 102 patients (63 men/39 women); mean age 60.6±9.7 years, with lung (n=63), melanoma (n=21), kidney (n=11), gastric (n=3), colon (n=3) or bladder (n=1) cancer. Only 7 patients had a previous diagnosis of an immune-mediated disease, specifically: psoriasis (n=2), psoriatic arthritis (n=1), systemic lupus erythematosus (n=1), spondyloarthitis (n=1), rheumatoid arthritis (n=1) and cutaneous lupus (n=1). One of the following ICBT was administered: nivolumab (n=52), pembrolizumab (n=35), atezolizumab (n=10) and ipilimumab (n=5). After a mean follow-up time of 14.4±7.7 months since ICBT onset, 87 (85.3%) patients had experienced irAEs, mostly gastrointestinal, thyroid and musculskeletal manifestations including inflammatory arthralgia (n= 8), arthritis (n= 6) and myositis (n=2). ICBT was discontinued in 41 patients but it was reintroduced in 30 of them after resolution of the adverse event, with a good tolerance in all cases. Thirty-six (41.4%) of the 87 patients required specific treatment (prednisone, levothyroxine, and thiamazol) for the irAEs.

irAEs are frequent in patients undergoing ICBT. Almost half of the patients that have irAEs require treatment. Musculoskeletal manifestations are not uncommon.