Primary, unilateral ocular adnexal lymphoma: disease progression and long-term survival.

Purpose: This investigation aimed to improve our understanding of the disease characteristics and clinical course for primary unilateral ocular adnexal lymphoma (OAL).
Methods: In this retrospective case series, all consecutive biopsy confirmed cases of lymphoma confined to a single ocular adnexa (unilateral stage 1E) during a 30-year period were included. All histologic classification conformed to the current World Health Organization classification. Descriptive statistics and standard survival analyses were performed.
Results: 122 patients were included in this study. The most common primary unilateral OAL were indolent B-cell lymphomas (mucosa-associated lymphoid tissue (MALT)-type marginal zone, follicular and small lymphocytic lymphoma) representing 80% of cases. Typically aggressive lymphomas were found in only 7% of patients (diffuse large B-cell lymphoma, immunoblastic lymphoma, diffuse large cell lymphoma, and mantle cell lymphoma). Overall, 24.4% of patients experienced progression of their disease after initial therapy, the majority occurring within 5 years. For the 80% of OAL of indolent B-cell type, progression free and disease specific survivals were 71 and 98% at 5 years and 61 and 90% at 10 years, respectively. Diffuse large B-cell lymphoma was more likely to progress overall (p < 0.01) and progress earlier (log rank, p < 0.01). Additionally, these patients were also more likely to succumb to disease (p < 0.01) in a shorter interval (log rank, p < 0.01).
Conclusion: Most primary unilateral OALs are indolent lymphomas with good prognosis for survival and freedom from progression. However, a minority present with more aggressive lymphomas (diffuse large B-cell lymphoma, mantle cell lymphoma, immunoblastic lymphoma, and diffuse large cell lymphoma), carrying a more guarded prognosis.