Sclerosing variant of follicular lymphoma arising from submandibular glands and resembling "Küttner tumor": a report of 3 patients.

We present 3 patients with a sclerosing variant of follicular lymphoma that arose from the submandibular gland and resembled "Küttner tumor." All 3 patients developed a painless unilateral tumor in the submandibular region. Histologically, all 3 lesions were categorized as follicular lymphoma grade 2. The neoplastic follicles were found to be separated by thick connective tissue, and periductal chronic inflammation with periductal fibrosis and duct ectasia was found in the residual atrophic gland. Immunohistochemistry revealed that all of the lesions contained a monoclonal tumor cell population. The immunophenotyopes of the lymphoma cells were CD 10+, CD 20+, CD 79a+, BCL-6+, CD 3-, CD 5-, CD 21-, CD 23-, CD 43-, CD 45RO-, BCL-2-, and Cyclin D1-. Two of the 3 patients exhibited clonal bands for the IgH gene by polymerase chain reaction assay. "Küttner tumor," which is a common fibrosing, chronic inflammatory lesion of the submandibular gland, is sometimes diagnosed as a malignant tumor. This study indicates that this sclerosing variant of follicular lymphoma should be added to the list of different diagnoses for "Küttner tumor."