[Local recurrence of ureteral tumor histologically similar to malignant lymphoma: a case report].

A 65-year old man, who had had resection of a right ureter tumor two years earlier, was hospitalized with complaints of lower abdominal discomfort and hematuria. Pathological diagnosis of the ureteral tumor was grade 3 transitional cell carcinoma. Computed tomography and magnetic resonance imaging demonstrated a large tumor in the retrovesical space and recurrence of transitional cell carcinoma was suggested. Total pelvic exenteration was performed and pathological diagnosis of the tumor was undifferentiated carcinoma simulating malignant lymphoma. Immunohistochemical examinations revealed no antigens specific for the lymphoid cells or epithelial cells on the specimen. This tumor consisting of undifferentiated carcinoma was considered to be recurrence of transitional cell carcinoma with the diffuse pattern simulating malignant lymphoma proposed by Zukerberg et al.