[Metachronous bilateral primary malignant lymphoma of the testis: a case report].

A 72-year-old man was referred to our department with the chief complaint of painless swelling of the left scrotum in May 1997. Left high orchiectomy was performed under the diagnosis of primary testicular tumor. Histological findings revealed non-Hodgkin's lymphoma (NHL) of diffuse, mixed type, B cells. No evidence of tumors in any other site was detected by further examinations. About 3 years and a month earlier, he had undergone right high orchiectomy and postoperative radiotherapy (inverted Y irradiation) and chemotherapy (CHOP 5 cycles) for a right testicular tumor whose histological findings were NHL of diffuse, large cell type, B cells. Metachronous bilateral primary malignant lymphoma of the testis is very rare and we discussed each tumor origin by using IgH gene (IgJHDNA) rearrangement as a tumor specific marker of B cell lineage malignant lymphoma. We discussed the clonality of IgJHDNA rearrangement using polymerase chain reaction (PCR) in each paraffin fragment diagnosed pathologically as NHL of B cell origin.