Combination Chemotherapy and Pegfilgrastim in Treating Patients With Previously Untreated Germ Cell Tumors

DISEASE CHARACTERISTICS: * Histologically confirmed germ cell tumor meeting 1 of the following criteria: * Poor risk, defined by any of the following: * Testis or retroperitoneal primary site nonseminoma histology without visceral metastases but with "poor-risk" markers, defined by any of the following: * Pretreatment serum lactate dehydrogenase (LDH) \> 10 times upper limit of normal (ULN) * Pretreatment serum human chorionic gonadotropin (HCG) \> 50,000 IU/L * Pretreatment serum alpha fetoprotein (AFP) \> 10,000 ng/mL * Testis or retroperitoneal primary site nonseminoma histology with one or more nonpulmonary visceral metastases, including any of the following (regardless of serum tumor marker values): * Bone metastases * Brain metastases * Hepatic metastases * Any nonpulmonary metastases (i.e., skin, spleen) * Mediastinal primary site nonseminoma histology regardless of serum tumor marker levels or presence/absence of visceral metastases * Modified intermediate risk, defined by any of the following: * Testis or retroperitoneal primary site nonseminoma histology with no nonpulmonary visceral metastases, and with any of the following serum marker values: * Pretreatment serum LDH 3.0-10 times ULN * Pretreatment serum HCG 5,000-50,000 IU/L * Pretreatment serum AFP 1,000-10,000 ng/mL * Seminoma histology with one or more nonpulmonary visceral metastases, including any of the following (regardless of serum tumor marker values or primary site): * Bone metastases * Brain metastases * Hepatic metastases * Any nonpulmonary visceral metastases (i.e., skin, spleen) * Previously untreated disease * Measurable or evaluable disease PATIENT CHARACTERISTICS: * WBC ≥ 3,000/mm\^3 * Platelet count ≥ 100,000/mm\^3 * Creatinine normal or creatinine clearance \> 50 mL/min (unless renal dysfunction is due to tumor obstructing the ureters) * AST and ALT ≤ 3 times ULN * Bilirubin ≤ 2.0 times ULN * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * No concurrent malignancy except for nonmelanoma skin cancer * No known HIV positivity * No active infections PRIOR CONCURRENT THERAPY: * Recovered from prior surgery * More than 30 days since prior radiotherapy and recovered (unless evidence of progressive disease has been documented) * No prior chemotherapy * No other concurrent cytotoxic therapy * Concurrent radiotherapy and surgery allowed for treatment of brain metastases