Characteristics of primary extranodal marginal zone B-cell lymphoma in Korea: conjunctiva versus other ocular adnexa

Aims To compare the clinical characteristics and prognosis of primary conjunctival versus other ocular adnexal extranodal marginal zone B-cell lymphoma (EMZL). Methods Retrospective review of clinical records for all consecutive patients with primary ocular adnexal EMZL treated from March 1995 to December 2015. Results 198 patients were evaluated including 81 with primary conjunctival and 117 with other ocular adnexal EMZL. Conjunctival EMZL was found at a younger age (40.310.3vs 54.3 +/- 13.4 years, p<0.0001) with a female predilection (75.3%vs35.9%, p<0.0001) and had a higher rate of bilaterality (40.7%vs11.1%, p<0.0001) and a lower rate of systemic involvement (1.2%vs9.4%, p=0.030) compared with other ocular adnexal EMZLs. Conjunctival EMZL also showed a higher rate of complete response to primary treatment (98.8%vs89.5%, p=0.016) than other ocular adnexal EMZLs; however, recurrence and lymphoma-related death rates were not different between the two groups (p>0.05). Kaplan-Meier estimates for disease-specific survival at 5 and 10 years were 98.2% and 98.2% in conjunctival and 98.6%, respectively, and 95.2% in other ocular adnexal EMZLs. Univariate analysis showed that systemic involvement was negatively associated with conjunctival tumour location and positively associated with age (OR=0.35and OR=1.05, p=0.045and p=0.012, respectively), and treatment response was positively associated with conjunctival tumour location and negatively associated with age (OR=3.02and OR=0.95, p=0.035and p=0.009, respectively). Conclusions Conjunctival EMZL shows unique demographic characteristic compared with other ocular adnexal EMZLs. Long-term follow-up is required due to late recurrence in ocular adnexal EMZL.