End-Of-Life Health Care Utilization (Eolhcu) In Patients With Recurrent, Metastatic Head And Neck Squamous Cell Carcinoma (Rmhnscc) Treated With Immune Checkpoint Inhibitors (Io).

e18516 Background: Demographic and EOLHCU trends are undefined in the growing population of IO-treated RMHNSCC; we sought to study these in a single institution retrospective study. Methods: We identified 228 RMHNSCC pts who received ≥1 IO dose between 01/2013 and 12/2018; of these, 74 were deceased with accessible EOLHCU data such as advanced care plan documentation (ACPD) or evidence of systemic therapy or ER/hospital/ICU admission within 30 days of death (DOD). Demographic, tumor and treatment data were obtained. Overall survival (OS) was estimated using the Kaplan Meier method; multivariable analysis was performed using a Cox proportional hazards model. In an exploratory analysis, EOLHCU was compared to a cohort of 379 deceased thoracic malignancy (TM) pts using a chi-square test. This project was approved by our institutional IRB. Results: Median pt age was 62 (25 – 90). Most were male (56, 75%), white (60, 81%), current/former smokers (46, 62%); 34 (46%) smoked ≥10 pack years. Common primary sites included the oral cavity (28, 37.8%) and oropharynx (24, 32.4%). ECOG PS at IO initiation was 0 in 15 pts (20%,) 1 in 37 (50%), 2 in 20 (27%), 3 in 1 (1%), and unknown in 1 (1%). Of the 42 (57%) treated off-trial, 18 (42%) had an ECOG ≥ 2. 71 (95%) had prior curative intent therapy. 42 (57%) had distant metastases. Compared to TM, IO-treated RMHNSCC pts were more likely to have ACPD (66% vs. 45% p < 0.01), an ED visit (42.3% vs 19.5%, p < 0.01) and/or a hospital admission (42.3% vs 17%, p < 0.01) within 30 DOD. There was no difference in ICU admissions within 30 DOD (9.9% vs. 8.2%, p = 0.81), ICU deaths (7% vs. 4%, p = 0.4), or systemic therapy within 7 (4.2% vs. 2.4%, p = 0.63), 14 (8.5% vs. 6.6%, p = 0.76) or 30 (25% vs 19%, p = 0.31) DOD. Among IO-treated RMHNSCC pts, multivariable analysis revealed inferior OS with worse PS (ECOG 2-3 vs. 0: HR = 7.76, p = 0.00002, 95% CI = 3.07 - 19.64; ECOG 1 vs. 0: HR = 2.97, p = 0.008, CI = 1.33 - 6.62). OS also decreased with smoking status (current/former vs. never: HR 2.18, p = 0.007, CI = 1.24-3.84). No association was observed between ECOG PS, age or smoking status at IO initiation and any EOLHCU metric. Conclusions: At our center, a significant proportion of deceased, IO-treated RMHNSCC pts had an ECOG PS ≥ 2 and an inferior OS compared to ECOG 0/1. Exploratory comparison with a non-RMHNSCC TM cohort suggests high rates of EOLHCU within 30 DOD despite ACPD, representing an opportunity for supportive care augmentation. Whether EOLHCU differs among IO vs non-IO treated RMHNSCC is unknown and merits further study.