ABSTRACT
PURPOSE: Immune-related cutaneous adverse events (ircAEs) occur in ≥50% of patients treated with checkpoint inhibitors (CPI), but mechanisms are poorly understood. EXPERIMENTAL DESIGN: Phenotyping/biomarker analyses were conducted in 200 patients on CPIs (139 with ircAEs, 61 without, control) to characterize their clinical presentation and immunologic endotypes. Cytokines were evaluated in skin biopsies, skin tape strip (STS) extracts and plasma using real-time PCR and Meso Scale Discovery multiplex cytokine assays. RESULTS: Eight ircAE phenotypes were identified: pruritus (26%), maculopapular rash (MPR; 21%), eczema (19%), lichenoid (11%), urticaria (8%), psoriasiform (6%), vitiligo (5%), and bullous dermatitis (4%). All phenotypes showed skin lymphocyte and eosinophil infiltrates. Skin biopsy PCR revealed the highest increase in IFN-gamma mRNA in patients with lichenoid (p<0.0001) and psoriasiform dermatitis (p<0.01) as compared to patients without ircAEs, while the highest IL-13 mRNA levels were detected in the eczema (p<0.0001, compared to control). IL-17A mRNA was selectively increased in psoriasiform (p<0.001), lichenoid (p<0.0001), bullous dermatitis (p<0.05) and MPR (p<0.001), compared to control. Distinct cytokine profiles were confirmed in STS and plasma. Analysis determined increased skin/plasma IL-4 cytokine in pruritus, skin IL-13 in eczema, plasma IL-5 and IL-31 in eczema and urticaria, and mixed-cytokine pathways in MPR. Broad inhibition via corticosteroids or type 2-cytokine targeted inhibition resulted in clinical benefit in these ircAEs. In contrast, significant skin upregulation of type 1/type 17 pathways was found in psoriasiform, lichenoid, bullous dermatitis, and type 1 activation in vitiligo. CONCLUSIONS: Distinct immunologic ircAE endotypes suggest actionable targets for precision medicine-based interventions.
ABSTRACT
Background: Immune-related cutaneous adverse events (ircAEs) are frequent and may reduce quality of life and consistent dosing. IL12/23 has been implicated in psoriasis, which is reminiscent of the psoriasiform/lichenoid ircAE phenotype. We report the use of ustekinumab as a therapeutic option. Methods: Patients at Memorial Sloan Kettering Cancer Center, New York, who received immune checkpoint inhibitors and were treated with ustekinumab or had the keywords "ustekinumab" or "Stelara" in their clinical notes between 1 March 2017 and 1 December 2022 were retrospectively identified via a database query. Documentation from initial and follow-up visits was manually reviewed, and response to ustekinumab was categorized into complete cutaneous response (CcR, decrease to CTCAE grade 0), partial cutaneous response (PcR, any decrease in CTCAE grade exclusive of decrease to grade 0), and no cutaneous response (NcR, no change in CTCAE grade or worsening). Labs including complete blood count (CBC), cytokine panels, and IgE were obtained in a subset of patients as standard of care. Skin biopsies were reviewed by a dermatopathologist. Results: Fourteen patients with psoriasiform (85.7%), maculopapular (7.1%), and pyoderma gangrenosum (7.1%) ircAEs were identified. Ten (71.4%) receiving ustekinumab had a positive response to treatment. Among these 10 responders, 4 (40%) demonstrated partial cutaneous response and 6 (60%) demonstrated complete cutaneous resolution. Six patients (42.9%) experienced interruptions to their checkpoint inhibitor treatment as a result of intolerable ircAEs, and following ircAE management with ustekinumab, two (33.3%) were successfully rechallenged with their checkpoint inhibitors. On histopathology, patients primarily had findings of interface or psoriasiform dermatitis. No patients reported an adverse event related to ustekinumab. Conclusions: Ustekinumab showed a benefit in a subset of patients with psoriasiform/lichenoid ircAEs. No safety signals were identified. However, further prospective randomized controlled trials are needed to confirm our findings.
