Primary cutaneous marginal zone B-cell lymphoma.

We report a Japanese case of primary cutaneous marginal zone B-cell lymphoma (PCMZL). This 46-year-old woman presented with a subcutaneous nodule on her right forearm. With the combined morphology,the immunophenotype, and molecular analysis, we diagnosed this lesion as PCMZL. Furthermore, we reviewed the 16 cases of PCMZL in the Japanese literature. The ages of the patients ranged from 26 to 75 years (mean 55.7 years) with a slight female predilection. Clinically, most of the skin lesions were erythematous nodular lesions. The involved regions were the face and neck in eight cases, the trunk in six and the arms in five. None had Borrelia burgdorferi infection or a history of thyroiditis. Two patients had suffered from Sjögren's syndrome. Histopathologically, lymphoepithelial lesions were found in nine cases. The chromosomal aberrations in MALT lymphoma such as t(11;18)(q21;q21), t(14;18)(q32;q21) and t(3;14)(p14.1;q32) were not reported in any of the Japanese cases. Although two patients developed metastasis on the skin after radiation therapy, none died of lymphoma.