A 5-year followup study of asymptomatic men with testicular microlithiasis.

PURPOSE: Testicular microlithiasis is an imaging entity of the testicle with questionable significance as a marker for testicular cancer. In 2001 we reported on a large prospective screening study establishing the prevalence of testicular microlithiasis to be 5.6% in a healthy asymptomatic population of Army volunteers 18 to 35 years old. In contrast, testicular cancer develops in only 5 of 100,000 men. Two-year followup of 63 of the 84 patients with testicular microlithiasis showed that none of these men had testicular cancer or scrotal masses. Here we report the 5-year followup in this cohort of men with testicular microlithiasis at risk for testicular cancer.

MATERIALS AND METHODS: According to the original parameters of the screening study we performed a history, genitourinary examination and scrotal ultrasound on 1,504 healthy army volunteers 18 to 35 years old during summer military training. Testicular microlithiasis was defined as greater than 6 echogenic signals found on ultrasound. We identified 84 patients with testicular microlithiasis (5.6%). These men were entered into the followup phase of the study and instructed regarding testicular self-examination and the need for followup. They were told to report any changes in their examination or a finding of testicular mass or cancer. Five years after the initial screening study we attempted to contact all remaining 84 men by e-mail, standard mail and telephone.

RESULTS: Of the original 84 men with testicular microlithiasis identified in the original screening study, 63 have been contacted via e-mail and by telephone (75%). Of the 63 subjects a mixed germ cell tumor developed in 1 patient 64 months after the initial screening study. Compared to the incidence of testicular cancer in the general population the odds ratio of developing testicular cancer in our study population is 317 (95% CI 36-2,756).

CONCLUSIONS: Testicular cancer will not develop in the majority of men with testicular microlithiasis (98.4%) during a 5-year followup interval. We believe that an intensive screening program for men with testicular microlithiasis is not cost-effective and would do little to improve outcomes associated with testicular cancer. We continue to recommend testicular self-examination in men at risk.