DISEASE CHARACTERISTICS:

• Histologically confirmed pure testicular seminoma or ovarian germ cell dysgerminoma

  • Histologic documentation of metastatic/recurrent disease not required
• Alpha-fetoprotein level must be normal, unless abnormal level is explained by other conditions and approved by the study chair
• Clinical stage II or III

• Progressive, refractory, or recurrent disease, meeting at least 1 of the following criteria:

  • Measurable progressive disease
  • Biopsy-proven residual disease
  • Persistently elevated or rising B-human chorionic gonadotropin (HCG) titers, defined as at least 2 values above the upper limit of normal (ULN)

• Cisplatin-refractory disease without option of potentially curative therapy, meeting 1 of the following criteria:

  • Failed high-dose chemotherapy with peripheral blood stem cell transplantation (PBSCT) or autologous bone marrow transplantation (AuBMT)
  • Ineligible for or refused PBSCT or AuBMT
  • Unlikely to achieve long-term benefit from PBSCT or AuBMT

• Current evidence of metastatic disease

  • Unidimensionally measurable target lesions

    • At least 20 mm by conventional techniques (e.g., physical examination for clinically palpable lymph nodes and superficial skin lesions or chest x-ray for clearly defined lung lesions surrounded by aerated lung) OR
    • At least 10 mm by spiral CT scan or MRI
    • If measurable disease is confined to a solitary lesion, then its neoplastic nature must be confirmed by histology
    • Ultrasound may not be used to measure tumor lesions that are not easily accessible clinically OR

• Non-measurable/non-target lesions, with HCG at least ULN, including the following:

  • Bone lesions
  • Pleural or pericardial effusions
  • Ascites
  • CNS lesions
  • Leptomeningeal disease
  • Irradiated lesions, unless progression documented after radiotherapy

PATIENT CHARACTERISTICS:

Age

• 15 and over

Performance status

• ECOG 0-2

Life expectancy

• Not specified

Hematopoietic

• Granulocyte count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3
• Hemoglobin at least 9 g/dL (transfusion allowed)

Hepatic

• Bilirubin no greater than 1.5 times upper limit of normal (ULN)
• SGOT/SGPT no greater than 2.5 times ULN

Renal

• Creatinine no greater than 1.5 times ULN

Other

• No other severe and/or uncontrolled concurrent medical illness
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective barrier contraception during and for 3 months after study participation

PRIOR CONCURRENT THERAPY:

Biologic therapy

• See Disease Characteristics

Chemotherapy

• See Disease Characteristics
• At least 4 weeks since prior chemotherapy
• No concurrent chemotherapy

Endocrine therapy

• No concurrent hormonal therapy except steroids for adrenal failure, hormones for non-disease-related conditions (e.g., insulin for diabetes), or intermittent dexamethasone as an antiemetic

Radiotherapy

• See Disease Characteristics
• At least 4 weeks since prior radiotherapy
• Prior radiotherapy to a symptomatic lesion or one that may produce disability (e.g., unstable femur) allowed
• No concurrent palliative radiotherapy

Surgery

• Not specified

Other

• No concurrent grapefruit juice
• No concurrent warfarin for therapeutic anticoagulation (concurrent mini-dose warfarin [1 mg orally per day] as prophylaxis allowed)