Background/AimsTo validate the prognostic performance of the American Joint Committee on Cancer (AJCC) eighth edition classification for ocular adnexal lymphoma (OAL).MethodsWe performed a retrospective review of 140 consecutive patients treated for primary OAL between March 2010 and September 2017. Associations between T/N/M categories at presentation and disease-related outcomes, including relapse, progression-free survival (PFS) and overall survival (OS) were evaluated.ResultsSeventy-nine women and 61 men (median age, 52 (range 20–84) years; median follow-up, 57 (range 7–131) months) were included. Histological subtypes included mucosa-associated lymphoid tissue lymphoma (92.1%, n=129), diffuse large B-cell lymphoma (5.0%, n=7), follicular lymphoma (1.4%, n=2) and mantle cell lymphoma (1.4%, n=2). Patients with ≥T2 disease had significantly higher risks of overall relapse (unadjusted HR)=4.32, p=0.016), decreased PFS (uHR=5.19, p=0.004) and decreased OS (uHR=9.21, p=0.047). Patients with ≥N1 disease had significantly higher risks of overall relapse (uHR=9.17, p<0.001) and decreased PFS (uHR=9.24, p<0.001). M1 disease was significantly associated with higher risks of overall relapse (uHR=3.62, p=0.036), decreased PFS (uHR=5.13, p=0.001) and decreased OS (uHR=9.24, p=0.013). On considering TNM categories as continuous data, the uHRs for per level increase in T, N and M categories were 1.77, 1.83 and 2.30 for overall relapse and 1.72, 1.87 and 2.78 for decreased PFS, respectively (p<0.05 for each comparison).ConclusionThe T, N and M categories of the AJCC eighth edition classification have prognostic value for relapse and survival among patients with primary OAL. Particularly, nodal/metastatic involvement at presentation indicated less favourable outcome.