A nomogram based prognostic score to predict overall survival (OS) in recurrent-metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) patients (pts) treated with immune checkpoint inhibitors (ICI)

Background ICIs are pivotal therapies in the treatment of pts with R/M HNSCC. The dismal OS of some pts underscores the need to detect pre-treatment prognostic scores. Methods Pts with R/M HNSCC receiving pembrolizumab (P) or nivolumab (N) were included in this retrospective analysis. We analyzed the impact of the following pre-treatment variables for OS using a Cox proportional hazards regression model: drug type, age, sex, tumor site, line of therapy, p-16, albumin (alb), hemoglobin (Hb), lactic dehydrogenase (LDH), lymphocyte count (LC), platelets (PLT), and neutrophil counts (NC). Results 66 pts (55%) treated with N and 55 (45%) with P were included. Characteristics: Sex: Male 100 pts (83%), female 21 pts (17%); Mean Age: 62 (SD 11); Performance Status 0-1: 63 pts (52%), 2-3: 58 pts (48%); Line of therapy, 1: 43 pts (36%), 2: 58 pts (48%), 3-4: 20 pts (16%); P-16: positive 44 pts (36%), negative 77 pts (64%); Tumor site: oropharynx 54 pts (45%), oral cavity 23 pts (19%), larynx 16 pts (13%), other 28 pts (23%); Response: complete 11 pts (9%), partial 3 pts (2%), stable disease 47 pts (39%); and disease progression: 60 pts (50%). The OS at 1 and 2 years were 52% (95% confidence interval (CI), 43%-62%) and 27% (CI 17%-42%), respectively. Age, sex, PLT, NC, LC, p-16, alb, Hb, and LDH were included in the multivariable Cox model. Adjusted hazard ratio estimates are: P-16: 0.53 (CI 0.3-0.95, P = 0.03); LC: 0.67 (CI 0.46-0.97, P = 0.03); NC: 1.25 (CI 1.01-1.56, P = 0.04); LDH: 1.67 (CI 1.01-2.78, P = 0.04); Hb: 1.69 (CI 1.00-2.87, P = 0.05); alb: 1.69 (CI 0.94-3.02, P = 0.08); PLT: 1.06 (CI 0.82, 1.37, P = 0.7); Age: 1.02 (CI 0.78-1.34, P = 0.9); and Sex: 0.98 (CI 0.5-1.91, P = 0.9). This model was used to create a nomogram based prognostic score for 1 and 2 year OS probability and median OS time. Internal model validation using bootstrapped based bias corrected estimates showed Nagelkerke’s R2 = 0.18, calibration slope of 0.67, and C-index of 0.7. Conclusions Pre-treatment LC, NC as well as LDH, Hb, alb, and p-16 had the largest impact on OS based on a prognostic nomogram. The nomogram may help treatment decisions regarding ICI use in this population. Legal entity responsible for the study The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.