Abstract
BACKGROUND: Although studies have investigated the risk of second primary malignancies (SPMs) associated with lymphoma of various sites, limited studies have investigated this risk in patients with lymphoma originating within the ocular adnexa. We conducted a retrospective study to assess incidence of secondary malignancies in patients with a prior diagnosis of ocular adnexal lymphoma (OAL) and to determine latency periods and age-groups at increased risk for SPM occurrence. METHODS: Retrospective analysis was performed on data obtained from Surveillance, Epidemiology, and End Results (SEER) 9 database. Patients with an initial primary malignancy diagnosis of OAL between 1973 and 2015 were included in the study. Standardized incidence ratios (SIR) and excess absolute risks (EAR) compared to a SEER reference population with similar sex, race, age, and calendar year were computed for SPMs. Excess absolute risk is per 10,000 individuals; alpha of 0.05 was used. RESULTS: Of 1834 patients with primary ocular adnexal lymphoma, 279 developed a secondary malignancy during average follow-up of 110.03 months (+/- 88.46), denoting higher incidence than expected (SIR 1.20; 95% CI, 1.07 to 1.35; EAR 30.56). Amongst the primary lymphoma cohort, 98.7% (1810/1834) of patients had non-Hodgkin's lymphoma and amongst those that developed secondary malignancies, 99.6% (278/279) had non-Hodgkin's lymphoma. Patients exhibited increased incidence of lymphohematopoietic and non-lymphohematopoietic second malignancies and no secondary malignancies of the eye or orbit. Patients had increased incidence of secondary malignancies in the first year (SIR 2.07; 95% CI, 1.49 to 2.79; EAR 150.37) and 1-5 years following lymphoma diagnosis (SIR 1.24; 95% CI, 1.01 to 1.51; EAR 34.89). Patients with various OAL subtypes demonstrated differing patterns of site-specific and overall SPM risk. CONCLUSIONS: Patients with prior diagnosis of ocular adnexal lymphoma possess increased risk of hematologic and non-hematologic secondary malignancies. Risk of secondary malignancy could vary by lymphoma subtype. Patients with ocular adnexal lymphoma may benefit from regular surveillance to promote early detection of second primary malignancies.