title: Grover's-like drug eruption in a patient with metastatic melanoma under ipilimumab therapy.
abstract: BACKGROUND
  Dermatologic toxicity is an important adverse effect of immune checkpoint inhibitors targeting cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death 1 receptor (PD-1) or PD ligand 1 (PD-L1). Skin toxicity most commonly includes a maculopapular erythematous rash and pruritus. Rarely life threatening complications such as Steven's Johnson syndrome or toxic epidermal necrolysis may occur.
  
  
  METHODS
  Here we report the uncommon event of a drug-induced transient acantholytic dermatosis (Grover's disease) in a 73-year-old Caucasian male treated with ipilimumab for metastatic melanoma. Five weeks after initiation of therapy, the patient developed a widespread polymorphic papulovesicular dermatosis on the trunk and proximal extremities with intense pruritus. Skin biopsy showed acantholytic dyskeratosis with interface dermatitis consistent with a Grover's-like drug eruption.
  
  
  CONCLUSIONS
  These findings should raise awareness for uncommon immune-related dermatological toxicities of immunomodulatory antibodies targeting the CTLA-4 signaling axis. We recommend biopsies of unexpected skin lesions to rapidly identify dermatological adverse events of immune checkpoint inhibitors.
authors.affiliation: Cantonal Hospital Baselland, Institute of Pathology, Mühlemattstrasse 11, CH-4410 Liestal, Switzerland ; Translational Research Unit (TRU), Institute of Pathology, University of Bern, Murtenstrasse 31, CH-3010 Bern, Switzerland.
authors.forename: Viktor H
authors.initials: VH
authors.lastname: Koelzer
authors.affiliation: Division of Medical Oncology, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland.
authors.forename: Tobias
authors.initials: T
authors.lastname: Buser
authors.affiliation: Cantonal Hospital Baselland, Institute of Pathology, Mühlemattstrasse 11, CH-4410 Liestal, Switzerland.
authors.forename: Niels
authors.initials: N
authors.lastname: Willi
authors.affiliation: Division of Medical Oncology, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland.
authors.forename: Sacha I
authors.initials: SI
authors.lastname: Rothschild
authors.affiliation: Division of Medical Oncology, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Wicki
authors.affiliation: Cantonal Hospital Baselland, Mühlemattstrasse 11, CH-4410 Liestal, Switzerland.
authors.forename: Peter
authors.initials: P
authors.lastname: Schiller
authors.affiliation: Cantonal Hospital Baselland, Institute of Pathology, Mühlemattstrasse 11, CH-4410 Liestal, Switzerland.
authors.forename: Gieri
authors.initials: G
authors.lastname: Cathomas
authors.affiliation: Division of Medical Oncology, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland.
authors.forename: Alfred
authors.initials: A
authors.lastname: Zippelius
authors.affiliation: Cantonal Hospital Baselland, Institute of Pathology, Mühlemattstrasse 11, CH-4410 Liestal, Switzerland.
authors.forename: Kirsten D
authors.initials: KD
authors.lastname: Mertz
keywords: Autoimmunity; Drug eruption; Grover’s disease; Immune checkpoint inhibitors; Immunotherapy; Ipilimumab; Melanoma; Transient acantholytic dermatosis