Background: Approximately 5% of patients with testicular cancer harbour carcinoma in situ (CIS) in the contralateral testis. CIS will progress into invasive tumour in about 50% of cases within five years. The present study evaluated the effect of platinum containing chemotherapy on CIS.
Patients and methods: Thirty-three patients with disseminated germ-cell cancer and biopsy proven CIS of the testis were evaluated.
Results: CIS had disappeared in the first follow-up biopsy in 30 patients. Six patients had a relapse of CIS with or without invasive cancer after 30, 31, 47, 51, 76 and 95 months from start of chemotherapy. Two relapses were among six patients who initially received cisplatin, vinblastine and bleomycine and four among 27 patients who initially received cisplatin, etoposide and bleomycine. The estimated cumulative risk of CIS five and 10 years after chemotherapy was 21% and 42%, respectively. The estimated cumulative incidence of spermatogenesis was 64% and 81% at five and 10 years of follow-up, respectively.
Conclusion: Platinum containing chemotherapy may eradicate CIS. However, patients with CIS may develop invasive cancer in spite of chemotherapy. In the light of the present data, we recommend radiotherapy to the affected testicle in patients with CIS in the contralateral testis and in patients with bilateral testicular CIS. In patients with extragonadal disease and CIS in one testicle, orchiectomy of the affected testicle is recommended. In patients for whom future fertility is an important issue, follow-up including repeated biopsies can be offered for a period of at least 10 years.