Therapeutic Strategy Guided by PET-TDM for Patients With Seminoma

Inclusion Criteria shared: * Histologically proved seminoma after orchiectomy * Primary testicular or retroperitoneal * Normal alpha-fetoprotein before and after orchiectomy * No prior treatment with radiotherapy or chemotherapy * Age \>= 18 years * ECOG 0 to 2 * PNN \>= 1500, platelets \>= 100 000, bilirubin \<= the upper limit nromale * ASAT (SGOT) and ALAT (SGPT) \<= 1,5 x the upper limit nromale * Serum creatinine \<140 µmol / L (or clearance\> 60 mL / min) * Information and signed informed consent before inclusion in the study * Patient affiliated to a social security Specific inclusion criteria for cohort 1: * grade I Specific inclusion criteria for cohort 2: * grade IIB (retroperitoneal adenopathy diameter between 2 cm and 5 cm, regardless of the LDH) * grade IIC (retroperitoneal adenopathy diameter higher than 5 cm, regardless of the LDH) * grade III of good prognosis (supradiaphragmatic reach with ganglionic metastasis and LDH \< 2 times normal limit and/or supradiaphragmatic reach with pulmonary metastasis and LDH \< 2 times normal limit) either at initial diagnosis or relapse of a grade I seminoma) * PET-TDM positive (pathological fixation on metastatic lesions) Exclusion Criteria shared: * Patient infected by HIV, Hepatitis B or C * History, within 5 years, of cancer other than seminoma, except for treated skin cancer (Basal Cell) . * visceral metastasis * cerebral metastasis * Any physical or mental condition incompatible with the treatment (to the investigator discretion) * Uncontrolled or severe cardiovascular pathology * Uncontrolled or severe hepatic pathology * Persons deprived of liberty or under guardianship * Unable to undergo medical monitoring due to geographical, social or psychological reasons