Nimotuzumab in combination with intensity modulated radiotherapy improve survival in locally advanced head and neck squamous cell carcinoma (LA-HNSCC): A multicenter-based real-world study.

e18006 Background: Head and neck squamous cell carcinoma (HNSCC) is characterized by the high expression of epidermal growth factor receptor (EGFR). Randomized study has demonstrated a survival advantage associated with the use of EGFR antibody (C225) in conjunction with radiation in locally advanced HNSCC (LA-HNSCC). However, the role of EGFR antibody plus concurrent chemoradiotherapy (CCRT), especially in the intensity-modulated radiotherapy (IMRT) era, is still controversial. Therefore, we conducted a multicenter, retrospective real-world study to investigate whether adding nimotuzumab, a humanized EGFR antibody, to IMRT-based treatment could improve survival in LA-HNSCC (NCT04949503). Methods: All HNSCC patients treated between January 2015 and December 2018 from 8 hospitals in China were screened. Eventually, patients who completed at least 5 course of nimotuzumab were identified as study group and those who did not receive nimotuzumab were considered controlled group. Propensity score matching (PSM) was utilized to balance known confounding factors, such as clinical stage (AJCC 7 ed.), primary location, and so on. Overall survival (OS) and progression-free survival (PFS) were compared between two groups. The Log-rank test was rendered to examine the overall difference of two survival curves and the Cloglog transformation test was performed to compare two survivals at a fixed timepoint. Results: A total of 25442 patients were screened, 1931 patients were eligible and 612 patients (306 patients in each group) were matched by PSM for final analysis. The percentage of stage IV disease was approximate 80% in both groups, and the use of CCRT was 62.4% in study group and 65.4% in controlled group. Totally 250 (81.7%) patients received IMRT in study group and 275 (89.8%) patients received IMRT in controlled group. The follow up was cut off on Jan 19, 2023 and the median follow up time was 54.2 (95%CI: 52.7-55.9) months. Among the entire cohort, the addition of nimotuzumab was associated with improved OS (HR = 0.75, 95% CI: 0.57-0.99, Log rank p = 0.038; 3y-OS: 74.6% vs 63.3%, Cloglog p = 0.004) as well as significantly advantageous PFS (HR = 0.74, 95% CI: 0.58-0.96, Log rank p = 0.020; 3y-PFS: 57.7% vs 44.3%, Cloglog p = 0.009). Subgroup analysis revealed that stage IV, T1, N2, radiotherapy duration ≥ 6 weeks, without previous surgery and CCRT sub-cohort could gained more OS benefit from the addition of nimotuzumab. Beneficial subgroup for PFS included stage IV, T2, N2, radiotherapy duration ≥ 6 weeks, without previous surgery and CCRT sub-cohort. Conclusions: The addition of nimotuzumab to IMRT-incorporated treatment may provide both OS and PFS benefit for LA-HNSCC, in particular those with stage IV or N2 diseases, without previous surgery, receiving radiotherapy ≥ 6 weeks and CCRT. Clinical trial information: NCT04949503 .