Does Pathologic Response to Immunotherapy Differ in Australian and European Patients With Melanoma?
Posted: Friday, December 20, 2019
In the phase II OpACIN-neo trial, there appeared to be a trend toward higher pathologic response rates in Australian patients than in European patients, all of whom were treated with neoadjuvant ipilimumab plus nivolumab for macroscopic stage III melanoma. According to Irene L. Reijers, MD, of the Netherlands Cancer Institute, Amsterdam, and colleagues, the contrast in pathologic response rates in these patients is most likely due to differences in age and sex. These results of a post hoc analysis were presented at the European Society for Medical Oncology (ESMO) Congress 2019 in Barcelona (Abstract 1328P) and also published in the Annals of Oncology.
In the analysis, the investigators evaluated baseline patient characteristics, safety, and efficacy in terms of pathologic response from 48 European patients and 38 Australian patients in the OpACIN-neo trial. The median follow-up for European and Australian patients was 9.3 months and 6.9 months, respectively.
In the study, Australian patients were older than European patients (median age 60 years vs. 53 years), more likely to be men (65.8% vs. 50.0%), and more likely to have an unknown primary melanoma (36.8% vs. 20.8%). The authors found no difference in PD-L1 expression between the two groups.
The Australian patients exhibited higher pathologic response rates than their European counterparts (84.2% vs. 68.1%), as did patients aged at least 60 years compared with those younger than age 60 (91.2% vs. 64.7%) and male patients compared with female patients (83.7% vs. 63.9%). A multivariate analysis including continent, age, and sex exhibited an adjusted objective response of 1.85 for Australian patients versus European patients, 4.89 for patients older than age 60 versus those younger than age 60, and 2.50 for male versus female patients.
Disclosure: For full disclosures of the study authors, visit academic.oup.com.