Dermatologic toxicities to immune checkpoint inhibitor therapy: A review of histopathologic features

J Am Acad Dermatol. 2020 Oct;83(4):1130-1143. doi: 10.1016/j.jaad.2020.04.105. Epub 2020 Apr 29.


Antineoplastic agents that use the immune system have revolutionized cancer treatment. Specifically, implementation of immune checkpoint inhibitors, monoclonal antibodies that block cytotoxic T-lymphocyte-associated antigen-4, programmed cell death protein 1, or programmed cell death ligand 1 show improved and sustained responses in patients with cancer. However, these agents are associated with a plethora of adverse events, many manifesting in the skin. As the clinical application of cancer immunotherapies expands, understanding the clinical and histopathologic features of associated cutaneous toxicities becomes increasingly important to dermatologists, oncologists, and pathologists to ensure timely diagnosis and appropriate care. This review discusses cutaneous reactions to immune checkpoint inhibitors, focusing on histopathologic features.

Keywords: CTLA-4; PD-L1; PD1; adverse event; atezolizumab; avelumab; bullous pemphigoid; checkpoint inhibitor; cutaneous; durvalumab; immunotherapy; ipilimumab; lichenoid dermatitis; nivolumab; pembrolizumab; rash; skin; toxicity.

Publication types

  • Review

MeSH terms

  • Acantholysis / chemically induced
  • Acantholysis / pathology
  • Alopecia / chemically induced
  • Alopecia / pathology
  • Drug Eruptions / etiology*
  • Drug Eruptions / pathology
  • Humans
  • Immune Checkpoint Inhibitors / adverse effects*
  • Keratinocytes / drug effects
  • Lichenoid Eruptions / chemically induced
  • Lichenoid Eruptions / pathology
  • Nevus, Pigmented / drug therapy
  • Panniculitis / chemically induced
  • Panniculitis / pathology
  • Pemphigoid, Bullous / chemically induced
  • Pemphigoid, Bullous / pathology
  • Pruritus / chemically induced
  • Pruritus / pathology
  • Psoriasis / chemically induced
  • Psoriasis / pathology
  • Stevens-Johnson Syndrome / etiology
  • Stevens-Johnson Syndrome / pathology
  • Vitiligo / chemically induced
  • Vitiligo / pathology


  • Immune Checkpoint Inhibitors