['Testicular lymphoma is a rare extranodal presentation of non-Hodgkin lymphoma. The authors report long term follow-up information regarding a group of patients with testicular lymphoma evaluated at the Mayo Clinic and describe the outcome with special attention to patterns of recurrence.', 'The medical records of patients with testicular lymphoma seen at the Mayo Clinic between January 1970 and March 1993 were reviewed. Patients were included if they had evidence of testicular involvement at the time of diagnosis of lymphoma. Pathology specimens were reviewed for confirmation of diagnosis.', 'Sixty-two patients with a diagnosis of testicular lymphoma were identified. Their median age was 68 years, and 60 patients underwent orchiectomy as the initial therapeutic and diagnostic procedure. Most of patients (79%) had localized or regional disease at the time of presentation. Other treatment modalities after diagnosis included radiotherapy (37%), combination chemotherapy (37%), and combination chemotherapy and radiotherapy (16%). Although 88% of patients had no residual disease after primary treatment, 80% subsequently experienced disease recurrence. There was no significant difference in the rate of recurrence, including Ann Arbor Stage I disease. Treatment did not appear to affect the recurrence rate. At a median follow-up of 2.7 years, 60% of patients had died of disease. Late recurrences were observed, and there appeared to be no plateau in the disease free survival curve. In half (51%) of the patients with disease recurrence, only extranodal locations were involved. Thirteen patients experienced recurrence in the central nervous system, 11 of whom had parenchymal lesions. In 8 of these 13 patients, the central nervous system was an isolated site of disease recurrence.'] Is testicular lymphoma associated with a high incidence of extranodal recurrence?