Japanese case of follicular lymphoma of ocular adnexa diagnosed by clinicopathologic, immunohistochemical, and molecular genetic techniques

Background: Follicular lymphomas of the ocular adnexa are very rare in Japan, with only two reported cases. Case: A 44-year-old woman visited our clinic for treatment of ocular adnexal tumors in both eyes. Findings: Histologic examination showed that the neoplastic lesions consisted of atypical lymphoid cells, and the tentative diagnosis was malignant lymphoma. Immunophenotypic analyses by flow cytometry and immunohistochemistry showed that the atypical lymphoid cells expressed CD45, bcl-2, CD10, CD19, CD20, IgM, and kappa light chains. The cells were negative for CD5 and other T, natural killer, or myelomonocyte antigens. Southern blot hybridization demonstrated gene rearrangement bands in the immunoglobulin JH region. Fluorescence in situ hybridization studies showed a translocation at t(14,18)(q32,q21). Systemic evaluations detected enlargements of both the inguinal lymph nodes and parabronchial lymph nodes. Conclusion: Our results show that flow cytometry, molecular genetic analyses, and chromosomal examination can be useful in differentiating follicular lymphoma from marginal zone B cell lymphoma of mucosa-associated lymphoid tissue and reactive lymphoid hyperplasia.