Association of Weekly Cisplatin vs. Carboplatin and Paclitaxel with Outcomes among Patients with Head and Neck Cancer Treated with Definitive Chemoradiation

NCCN guidelines recommend weekly cisplatin and weekly carboplatin with paclitaxel as alternative concurrent systemic therapy regimens among patients with head and neck cancer undergoing definitive chemoradiation. However, there is a paucity of literature comparing outcomes with these two regimens. We performed an observational cohort study of patients with head and neck cancer treated with definitive chemoradiation receiving either weekly cisplatin or weekly carboplatin with paclitaxel. A single-institution database was queried for patients with head and neck cancer diagnosed between November 2011 and March 2020 who underwent chemoradiation with either weekly cisplatin (40 mg/m2) or weekly carboplatin (AUC 1) with paclitaxel (30 mg/m2). Cox multivariable analysis (MVA), Kaplan-Meier, Fine-Gray MVA, logistic MVA, and propensity score matching were performed to evaluate treatment outcomes. A total of 236 patients were identified (n = 160 with weekly cisplatin [n = 37 with p16-negative, n = 123 with p16-positive], n = 76 with weekly carboplatin and paclitaxel [n = 26 with p16-negative, n = 50 with p16-positive]). Median follow up was 47.7 months (interquartile range 40.8-56.8). The majority of patients received at least 5 weekly cycles during the treatment period (n = 142 [88.8%] for cisplatin, n = 64 [84.2%] for carboplatin and paclitaxel). On logistic MVA, those with older age (adjusted odds ratio [aOR] 9.58, 95% CI = 4.66-20.94, p<0.001), former smoking history (aOR 2.46, 95% CI = 1.03-6.21, p = 0.05), and worse performance status (aOR 3.85, 95% CI = 1.88-8.22, p<0.001) were more likely to undergo weekly carboplatin and paclitaxel, while those with non-Caucasian race (aOR, 0.14, 95% CI = 0.02-0.80, p = 0.05) and overweight body mass index (aOR 0.37, 95% CI = 0.15-0.91, p = 0.03) were less likely to receive weekly carboplatin and paclitaxel. After adjusting for baseline characteristics such as p16 status, age, smoking status, and performance status, weekly carboplatin and paclitaxel was associated with comparable overall survival (OS; adjusted hazards ratio [aHR] 1.24, 95% confidence interval [CI] 0.66-2.32, p = 0.50), progression-free survival (PFS; aHR 1.74, 95% CI = 0.99-3.07, p = 0.06), locoregional failure (LRF; aHR 2.62, 95% CI = 0.98-7.02, p = 0.06), and distant failure (DF; aHR 2.29, 95% CI = 0.94-5.57, p = 0.07) compared to weekly cisplatin. Similar findings were observed among 53 matched pairs for OS (5-year OS 64.2% vs 74.7%, p = 0.43), PFS (5-year PFS 57.7% vs 69.8%, p = 0.11), LRF (5-year LRF 12.5% vs 7.55%, p = 0.44), and DF (5-year DF 29.7% vs 12.7%, p = 0.09). Our study suggested that those treated with weekly carboplatin and paclitaxel had comparable survival and tumor control outcomes compared to those with weekly cisplatin. Older age and poor performance status were the strongest predictors associated with the receipt of weekly carboplatin and paclitaxel. Prospective studies comparing alternative chemotherapy regimens are warranted.