Published online Jul 24, 2022. doi: 10.5306/wjco.v13.i7.641
Peer-review started: February 5, 2022
First decision: May 12, 2022
Revised: June 1, 2022
Accepted: June 21, 2022
Article in press: June 21, 2022
Published online: July 24, 2022
The activation of immunocompetent cells by nivolumab exerts an antitumor effect. However, excessive immune responses developed in autologous organs along with the breakdown of self-tolerance causes immune-related adverse events (irAEs), such as hypothyroidism.
Low neutrophil-to-lymphocyte ratio (NLR) values have been shown to be associated with a favorable therapeutic response to nivolumab. The possibility that NLR is associated with immune response implies that NLR can be not only a predictive factor for good response to nivolumab but also a predictive factor for the development of hypothyroidism.
To evaluate whether continuous monitoring of NLRs during nivolumab treatment is useful for predicting the incidence and onset period of hypothyroidism.
NLR of patients who received nivolumab treatment was measured before each administration. NLR at treatment initiation was compared between patients with and without hypothyroidism during the treatment period. Patients who developed hypothyroidism were categorized into three groups as those with NLR < 3.5, NLR 3.5 to < 5, and NLR ≥ 5 according to their maximum NLR from treatment initiation to hypothyroidism development, and the onset periods of hypothyroidism were compared.
Patients with hypothyroidism showed significantly lower NLR at treatment initiation, and the incidence of hypothyroidism was higher among those with NLR < 5. Patients with persistently low NLR (< 3.5) developed hypothyroidism earlier than those with NLR 3.5 to < 5 and NLR ≥ 5.
Low NLR at treatment initiation increases the incidence of treatment-induced hypothyroidism. Moreover, its persistence may be a risk factor for the early onset of hypothyroidism.
The follow-up period in this study was limited to the 12th dose of nivolumab. The incidence of hypothyroidism should be evaluated throughout the treatment period.