Immunohistochemical and immunogenetic analyses of ocular adnexal lymphoid proliferation

To compare polymerase chain reaction (PCR) results with histological, immunohistochemical, and clinical findings to understand the nature of ocular adnexal lymphoid proliferation.

We examined 20 cases (21 specimens) of ocular adnexal lymphoid proliferation, using histological, immunohistochemical, and molecular genetic methods. The latter two types of experiments were performed to examine the light chain restriction of immunoglobulin using the peroxidase-antiperoxidase method, and the clonality of immunoglobulin heavy chains using the PCR method.

Although in 8 cases it could not be determined morphologically whether the tumors were neoplastic or not, clonality was revealed in 1 case by immunohistochemistry and in 4 cases by PCR. Two cases showed disparate results between immunohistochemistry and PCR, probably due to somatic mutation of the framework region of the immunoglobulin heavy chain gene.

Examination using these methods contributes to a better understanding of the nature of the ocular adnexal lymphoid proliferation. Furthermore, the immunoglobulin gene PCR method is very useful in practice for examination of specimens, as it can be used with formalin-fixed and paraffin-embedded specimens.