Impact of COVID19 pandemic on treatment outcome of locally-advanced head and neck squamous cell carcinoma (LA-HNSCC): IMPACCT study.

Abstract

6061 Background: Treatment (ttm) of cancer patients (pts) was compromised during the first wave of COVID19 pandemic due to collapse of healthcare systems. Standard of care (SOC) for LA-HNSCC pts had to be adapted as operating rooms were temporarily unavailable, and to reduce risk of COVID19 exposure. The IMPACCT study evaluated the outcome of LA-HNSCC pts treated at the Catalan Institute of Oncology during the first semester of 2020 and compared it to a control cohort previously treated in the same institution. Methods: Retrospective single institution analysis of two consecutively-treated cohorts of newly-diagnosed HNSCC pts: from January to June of 2020 (CT20) and same period of 2018 and 2019 (CT18-19). Pt demographics and disease characteristics were obtained from our in-site prospective database. Ttm modifications from SOC as per COVID19-contingency protocol in CT20 for LA-HNSCC were collected. Chi-squared was used to compare variables and ttm response between cohorts. One-year recurrence-free survival (1yRFS) and overall survival (1yOS) of LA-HNSCC pts were estimated by Kaplan-Meier method and compared by Log-rank test. Results: A total of 306 pts were included: CT20=99; CT18-19=207. Baseline characteristics were balanced between cohorts (Table1). In pts treated with conservative ttm (non-surgical approach), persistence disease was higher in CT20 vs CT18-19 (26 vs. 10% p=0.02). Median follow-up of CT20 and CT18-19 was 6.8 months (IQR 5.1-7.9) and 12.3 (6.7-18.4), respectively. A trend towards lower 1yRFS and 1yOS was observed in CT20 vs CT18-19 (72 vs 83% p=0.06; 80 vs 84% p=0.07), respectively. Within CT20, 37 pts (37%) had one or more ttm modifications: switch from surgery to conservative ttm (n=13); altered radiotherapy fractionation (n=14); reduced cisplatin cumulative dose to 200mg/m2 (n=19); no adjuvant ttm (n=1). Pts who received modified ttm had no differences in 1yRFS vs those who did not (80 vs 66% p=0.31), but higher 1yOS was observed (97 vs 67% p<0.01). When stratified by stage, 1yOS difference remained significant in stage III/IVA (100 vs 61% p<0.01) but not in I/II (100 vs 77% p=0.28) or IVB (67 vs 50% p=0.54). Conclusions: COVID19 pandemic had a negative impact on ttm outcomes and survival in LA-HNSCC pts when compared to our historical cohort. Ttm modifications based on COVID19-contingency protocol did not compromise ttm efficacy in terms of RFS and was associated with better OS in Stage III/IVA.[Table: see text]