Cutaneous toxicities of anti-programmed death (anti-PD-1) antibodies in patients with advanced solid organ tumours

Introduction: Despite the emergence of patients with advanced solid organ tumours such as non-small-cell lung cancer and genitourinary cancers treated with anti-Programmed death 1 (anti-PD1) antibody, there is a lack of literature describing cutaneous adverse events (AEs) observed in this population. We aim to describe anti-PD1 induced cutaneous AEs in patients with advanced solid organ tumors and compare them between the solid organ and melanoma groups.
Methods: Medical oncology and dermatology teams prospectively reviewed all patients with advanced solid organ tumours receiving anti-PD1 therapy from July 2012 to February 2016 enrolled in clinical trials at Westmead Hospital, Sydney, Australia. These data were compared to our previously published data on patients with metastatic melanoma treated with anti-PD1 therapy.
Results: Of 54 patients with advanced solid organ tumours, 48% of patients developed new cutaneous AEs. Most frequently reported lesions were rash* (33%) and pruritus (15%). There was a statistically significant association between increasing age and first pruritus (HR = 2.5 per decade of age, P = 0.027) in solid organ group, however no statistically significant differences were found in developing rash*(HR 0.909, P= 0.755), pruritus (HR 0.646, P= 0.371) and vitiligo (HR 0.133, P= 0.053) between solid organ and melanoma groups.
Conclusion: We found no statistically significant differences in cutaneous AEs observed in patients with solid organ tumours and melanoma treated with anti-PD1 antibody. Early characterisation of various cutaneous AEs will prevent unnecessary cessation of immunotherapies. Future studies are needed to better understand the underlying pathogenesis of these AEs.

Dr. Shelley Ji Eun Hwang

Westmead Hospital, Sydney, Australia

My name is Shelley Ji Eun Hwang, a first year dermatology registrar currently working at Skin and Cancer Foundation at Darlinghurst and St Vincent's hospital. I have previously worked as a dermatology research fellow at Westmead Hospital, Sydney under the supervision of A/Prof Fernandez-Penas.