Carcinoma in situ of the testis and bilateral carcinoma.

Carcinoma in situ of the testis is being recognized with increasing frequency and may be increasing in absolute terms. The circumstances in which CIS should be suspected are well defined, and the opportunity exists of intervening before an invasive tumor is evident, thus sparing the testis. External radiation appears effective, although experience is limited. Finally, bilateral testis cancer may be increasing in frequency; although treatment plans must be individualized, the ultimate outcome remains excellent.