1097P - PD-L1 expression and overall survival among patients with melanoma

Date 28 September 2014
Event ESMO 2014
Session Poster Display session
Topics Melanoma and other Skin Tumours
Pathology/Molecular Biology
Presenter Torben Steiniche
Citation Annals of Oncology (2014) 25 (suppl_4): iv374-iv393. 10.1093/annonc/mdu344
Authors T. Steiniche1, A.V. Danielsen1, Z. Wang2, P.S. Nielsen1, L. Bastholt3, H. Schmidt4, I.M. Svane5, M. Dolled-Filhart6, K. Emancipator7, R. Weiner6, M. Busch-Sorensen8, W. Zhou9
  • 1Institute Of Pathology, Aarhus University Hospital, 8000 - Aarhus/DK
  • 2Bards, Merck Sharp & Dohme, Beijing/CN
  • 3Onkologisk Afdeling R, Odense University Hospital, 5000 - Odense C/DK
  • 4Oncology, Aarhus University Hospital, Aarhus/DK
  • 5Department Of Oncology And Of Haematology, University Hospital Herlev, DK-2730 - Herlev/DK
  • 6Molecular Biomarkers And Diagnostics, Merck & Co., Inc., Rahway/US
  • 7Molecular Biomarkers And Diagnostics, Merck Research Laboratories, Rahway/US
  • 8Epidemiology, Merck & Co., Inc., Ballerup/DK
  • 9Epidemiology, Merck Research Laboratories, North Wales/US

Abstract

Aim

Recent clinical trial results suggest programmed cell death ligand-1 (PD-L1) expression may predict response to anti-PD-1 therapy. There are conflicting data regarding PD-L1 expression as a prognostic factor among patients with melanoma treated with standard of care (SOC) therapies.

Methods

We evaluated the relationship between PD-L1 expression and overall survival (OS) in 223 melanoma patients diagnosed in Denmark between 2001 and 2010. Tumor PD-L1 expression was measured using a prototype immunohistochemistry assay with the 22C3 antibody, and PD-L1 positivity was defined as staining in ≥1% of cells. Analyses of PD-L1 expression with survival outcomes were performed using Cox proportional hazards models, Kaplan-Meier methods, and the log-rank test, adjusting for age, gender, stage, and performance status.

Results

Median (range) age was 59 years (19-90), and 36% of patients were female. At diagnosis, 48% had stage I-IIIA disease and 45% had stage IIIB-IV disease (6% had missing stage information). 88% of the tumor samples were collected within 6 months of diagnosis. 212 patients received surgery as initial therapy. Among the 167 patients who received chemotherapy or immunotherapy, 17% received 1 regimen, 43% received 2 regimens, and 40% received 3+ regimens. The first-line regimen, excluding adjuvant therapy, was interleukin-2 or interferon (49%), temozolomide (24%), ipilumumab (19%), vemurafenib (3%), or other (5%). 49% of patients were PD-L1 positive. There was no significant association between PD-L1 expression and OS from time of diagnosis, with an adjusted hazard ratio (AHR) of 0.71 for the PD-L1–positive group versus the PD-L1–negative group (95% confidence interval [CI], 0.42-1.21; n = 108) among stage I-IIIA patients, and 1.12 (95% CI, 0.66-1.88; n = 101) among stage IIIB-IV patients. There was also no association between PD-L1 expression and OS among ipilimumab-treated patients (n = 136), with a 1-yr survival rate of 45% (95% CI, 32%-57%) in the PD-L1–positive group and 47% (33%-60%) in the PD-L1–negative group (AHR, 0.93; 95% CI, 0.60-145).

Conclusions

Our results do not suggest that PD-L1 is a strong prognostic factor among patients with melanoma treated with SOC therapies, including immunotherapy.

Disclosure

T. Steiniche: Corporate-sponsored research–Merck Sharp & Dohme; Z. Wang: Full-time employment–Merck & Co., Inc.; M. Dolled-Filhart: Full-time employment–Merck & Co., Inc.; K. Emancipator: Full-time employment–Merck & Co., Inc.; R. Weiner: Full-time employment–Merck & Co., Inc.; M. Busch-Sorensen: Full-time employment–Merck & Co., Inc.; W. Zhou: Merck Research Laboratories–Full-time employment with stock ownership.; All other authors have declared no conflicts of interest.