A case of primary MALT lymphoma of the endometrium presenting as an asymptomatic polyp

Dear Editor,Herein, we present the case of an 81-year-old Caucasianwoman who received a diagnosis of breast cancer in March2006. During staging procedures, a transvaginal echogra-phy revealed an endometrial polyp that was removed a fewmonths later, after the completion of the breast cancertherapeutic program.At microscopic examination, the polyp was character-ized by numerous cystically dilated glands, mainly locatedat its periphery (Fig. 1). The stalk was diffusely infiltratedby a lymphomatous population consisting of small-sizedelements with slightly indented nuclei, moderately dis-persed chromatin, inconspicuous nucleoli, and a narrow rimof clear cytoplasm (Fig. 1). Such population tended tofocally invade the glandular component giving rise tolymphoepithelial lesions and to colonize and substitutepreexisting germinal centers. As a consequence of the latterevent, a few centroblasts were scattered throughout theneoplastic growth. At immunohistochemistry, the lympho-matous population expressed the B-cell markers CD20 andCD79a, as well as the marginal zone-associated moleculeimmune receptor translocation associated 1 (IRTA1; Fig. 1).In the areas corresponding to germinal center colonization,neoplastic cells—always CD10 negative—showed faintpositivity for Bcl-6, in contrast to residual germinal centerB-cells that strongly expressed both Bcl-6 and CD10 (Fig.1). The Ki-67 marking accounted for less than 5% of thewhole neoplastic population (Fig. 1). Based on thesefindings, a diagnosis of extranodal marginal zone B-celllymphoma of mucosa-associated lymphoid tissue (MALTlymphoma) arising in an endometrial polyp was made.Fever, night sweating, loss of weight, and local signs orsymptoms were absent at diagnosis. The blood cell countrevealed only a mild normocytic and normochromic anemiaassociated with a mild increase of erythrocyte sedimenta-tion rate. Serum