[High Orchidectomy and Histopathology to Differentiate Granulomatous Orchitis from Testicular Malignancy : Case Report and Literature Review].

: A 59-year-old man presented with pain and swelling of the right scrotum. Magnetic resonance imaging revealed a mass withsignal intensity similar to background on an apparent diffusion coefficient (ADC)-map of the upper region of the right testis. Inflammation was considered, but a testicular tumor could not be ruled out. Right high orchidectomy and histopathological assessment revealed granulomatous orchitis. The cause, clinical course and treatment of rare granulomatous orchitis remain unknown. Granulomatous orchitis and testicular tumor are difficult to discriminate, and high orchidectomy is usually applied along with histopathological assessment to achieve a definitive diagnosis. On the other hand, some patients who were only medically treated for granulomatous orchitis have recovered. We recently found that diffusionweighted imaging and ADC values derived from magnetic resonance images can differentiate testicular tumor from orchitis. We suggest an algorithm for the diagnosis and treatment of granulomatous orchitis considering the present patient and previous reports.