Primary ocular-adnexal non-Hodgkin Lymphoma in a Peruvian cohort: An 18-year experience

BACKGROUND: Primary ocular-adnexal non-Hodgkin lymphoma (POANHL) is a rare malignancy, but the most common tumor of the ocular adnexa. Data on real-world outcomes in Hispanic-Latino populations are limited, despite potential geographic and biologic differences. We describe the treatment and outcomes of POANHL in a Peruvian cohort and identify factors associated with survival outcomes. METHODS: We conducted a retrospective cohort study including all patients diagnosed with localized POANHL (stage I and II) at a tertiary referral center between 2000 and 2017. Survival outcomes were estimated using Kaplan-Meier methods, and Cox proportional hazards models were used to identify prognostic factors for event-free survival (EFS) and overall survival (OS). RESULTS: A total of 98 patients were included. The mean age was 58.0 ± 17.5 years. The orbit was the most frequently involved site (42.8%), followed by the eyelid (29.6%) and the conjunctiva (27.6%). The most common associated lymphomas were extranodal marginal zone lymphoma (50.0%), diffuse large B-cell lymphoma (23.5%), and follicular lymphoma (7.1%). Most patients presented with stage I disease (80.6%), good performance status (ECOG 0-1: 88.8%), and low international prognostic index (0-1: 69.6%). Treatment included chemotherapy (39.2%), radiotherapy (24.5%), combined modality therapy (12.2%), and observation/no treatment (35.7%). Cyclophosphamide, vincristine, doxorubicin, and prednisone-based regimens were the most commonly used chemotherapy backbone. Complete response (CR) was 45.6% among treated patients. With a median follow-up of 20.2 years, 5-year OS and EFS were 94.8% and 79.2% for indolent lymphomas, and 59.7% and 42.8% for aggressive lymphomas respectively. On multivariable analysis, older age was independently associated with worse outcomes in indolent lymphoma, both for EFS (HR = 1.084, 95%CI 1.028-1.142) and OS (HR = 1.092, 95%CI: 1.037-1.150). In aggressive lymphoma, treatment modality was the only independent prognostic factor for DFS, with chemotherapy (HR 0.135, 95% CI 0.031-0.595; p = 0.008) and chemoradiotherapy (HR 0.112, 95% CI 0.023-0.547; p = 0.007) associated with improved outcomes vs. observation; radiotherapy showed a non-significant trend (HR = 0.200, 95%:CI 0.033-1.203). No variables were independently associated with OS in aggressive lymphoma. CONCLUSIONS: We report real-world outcomes of POANHL in a Hispanic-Latino cohort, demonstrating distinct clinical characteristics and survival outcomes compared with previously published series.