Primary Non-Hodgkin Lymphoma of the Parotid Gland Associated with Sjögren's Syndrome: A Case Report

Malignant lymphoma of the ocular adnexa associated with the benign lymphoepithelial lesion of the parotid glands. Report of two cases

BACKGROUND

The benign lymphoepithelial lesion of the salivary/lacrimal glands is generally regarded as a lymphoproliferative disorder that may be associated with Sjögren syndrome. Although lymphomatous transformation in patients with Sjögren syndrome is well documented, few reports have appeared describing similar findings in patients with a benign lymphoepithelial lesion.

METHODS

The authors report the unusual occurrence of malignant lymphoma involving the ocular adnexa in two patients with a histopathologically documented benign lymphoepithelial lesion of the parotid glands.

RESULTS

Both patients developed B-cell lymphomas. The eyelid tumor in case 1 expressed IgM/kappa cell surface markers by flow cytometry, and the orbital/conjunctival masses in case 2 showed neoplastic nodules of B cells that were only immunoreactive to lambda light chains (avidin-biotin complex method).

CONCLUSION

To the authors' knowledge, this is the first report of ocular adnexal lymphoma arising in patients with a benign lymphoepithelial lesion of the parotid glands. This report establishes that ocular adnexal lymphoma may arise in a patient with a preexisting benign lymphoepithelial lesion.

Uniform detection of immunoglobulin-gene rearrangement in benign lymphoepithelial lesions

The term "benign lymphoepithelial lesion" is used to describe the salivary-gland lymphocytic infiltration and epithelial changes typically found in association with Sjögren's syndrome. We used Southern blot hybridization techniques to examine the immunoglobulin genes in salivary-gland tissue derived from eight patients with benign lymphoepithelial lesions. Three of these patients had intrasalivary non-Hodgkin's lymphoma complicating the lesions, whereas the lesions in the remaining five were all histologically benign. Ten samples from the eight patients all revealed rearrangement of both the heavy-chain and light-chain immunoglobulin genes. In one of the patients in whom non-Hodgkin's lymphoma involved both the salivary-gland lesion and an ipsilateral lymph node, the rearrangements of the heavy-chain and light-chain immunoglobulin genes detected at the two sites were identical. One other patient had two distinct benign lymphoepithelial lesions removed two years apart. The rearrangements of the heavy-chain as well as the kappa light-chain genes detected in these two lesions were entirely different. These data suggest that B-cell clonal expansion has an integral role in the pathophysiology of the benign lymphoepithelial lesion and may explain the increased incidence of lymphoma noted in association with this disorder.