As testicular ultrasound has evolved, nonpalpable masses have been detected for which an evaluation and treatment protocol has not been established. Our experience with nonpalpable testis masses detected only by ultrasound in 5 patients is presented, with all patients found to have nonmalignant lesions. We recommend that such cases with negative serum tumor markers and normal chest radiographs be followed with serial ultrasounds. Benign masses will resolve completely, while stable or enlarging masses can be locally excised and inguinal orchiectomy completed only if cancer is found by frozen section. A modified staging system to follow these patients is proposed to determine these patients' prognoses: Stage Ia for inguinally removed nonpalpable cancers, Stage Ib for excised nonpalpable cancers without orchiectomy (false-negative frozen section), and Stage Ic for inguinally removed palpable cancers.