Isolated Neutropenia Due to Immune Checkpoint Inhibitors

Abstract

In this article, we explore the correlation between immune checkpoint inhibitors (ICIs) and neutropenia. Immune checkpoint inhibitors have revolutionized cancer treatment and management by maximizing the innate abilities of the immune system. However, this therapeutic potential is accompanied by a range of immune-related adverse effects (irAEs), including neutropenia, which is a rare but potentially life-threatening side effect of this mode of cancer treatment. Through an in-depth analysis of various case reports, we have compiled a detailed table summarizing the occurrences of neutropenia associated with different ICIs, the grades of neutropenia, treatments used, and patient outcomes. Management of neutropenia must include an approach based on early diagnosis of the condition and a treatment based on its severity. This review discusses different therapeutic interventions, ranging from the administration of corticosteroids and intravenous immunoglobulin (IVIG) to the use of granulocyte colony-stimulating factor (filgrastim) and, in very severe cases, a stem cell transplant. We have also enlisted salient side effects caused by these interventions. Our findings emphasize that while neutropenia is a relatively rare adverse effect of ICIs, its severity necessitates increased awareness among healthcare professionals. As ICIs continue to be seen as an integral component of cancer therapy, a comprehensive understanding of neutropenia as a side effect and its management is critical for optimizing patient outcomes. A crucial purpose of this review is to highlight the need to achieve a balance between acquiring the therapeutic benefits of various treatment strategies for irAEs and considering their potential side effects, especially with the use of steroids. Achieving this equilibrium is very important in optimizing patient care during immunotherapy, as these irAE management options can both mitigate the neutropenia triggered by ICIs and potentially give rise to secondary complications. Therefore, a careful assessment of the risks and benefits associated with each treatment approach is essential in tailoring irAE management.