ESTRO meets Asia 2024 - Abstract Book

S163

Interdisciplinary – Head & neck

ESTRO meets Asia 2024

Purpose/Objective:

The impact of 24-month progression-free survival (PFS24) on subsequent overall survival (sOS) and loss of lifetime (LoL) was examined in a large multicenter nasopharyngeal carcinoma (NPC) patient cohort and compared with a matched general population.

Material/Methods:

Non-metastatic NPC patients treated between 2007 and 2020 were enrolled from nonendemic and endemic cohorts. sOS was defined as survival from the point of 24-month or progression within a 24-month timeframe to mortality. LoL was defined as the reduction in life expectancy relative to the general population resulting from NPC. The standardized mortality ratio (SMR) represents the ratio between observed mortality and expected mortality. After adjusting for age, sex and calendar year, patients with or without achieving PFS24 were compared with the matched background population based on sOS, LoL, and SMR.

Results:

The study included 6315 patients. PFS24 was achieved in 5301 patients (83.9%), with a 5-year sOS of 90.2% and an SMR of 1.0 (95% confidence interval [CI], 1.0–1.1; Figure 1). Within 10 years following initial treatment, the mean LoL was only 0.01 mo/y (95% CI, -0.08–0.10 mo/y; Figure 2). For most subgroups, except for stage IVA, achieving PFS24 exhibited a comparable sOS with the background population and was accompanied by insignificant SMR and LoL. Patients failing to achieve PFS24 had markedly reduced outcomes, with a 5-year sOS of 21.9%, an SMR of 23.7 (95% CI, 23.5–24.1), and an LoL of 6.48 mo/y (95% CI, 6.09–6.82).

(Figure 1.)