DISEASE CHARACTERISTICS:

• Histologically confirmed metastatic or unresectable solid tumor for which no standard curative or palliative therapy exists or is no longer effective

• Brain metastases allowed provided the following treatment requirements are met:

  • Asymptomatic or clinically stable disease after surgery or radiotherapy
  • No concurrent requirement for steroids or antiseizure medications
  • More than 2 weeks since prior therapy (e.g., surgery or CNS irradiation) for brain metastases
  • Recovered from prior therapy

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• ECOG 0-2 OR
• Karnofsky 60-100%

Life expectancy:

• More than 12 weeks

Hematopoietic:

• WBC at least 3,000/mm^3
• Absolute neutrophil count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3

Hepatic:

• Bilirubin normal
• AST/ALT no greater than 2.5 times upper limit of normal

Renal:

• Creatinine normal OR
• Creatinine clearance at least 60 mL/min

Cardiovascular:

• See Radiotherapy
• History of coronary artery disease allowed provided LVEF is at least 45% by MUGA or echocardiogram
• No symptomatic cardiac disease

Pulmonary:

• History of pulmonary disease allowed provided FEV_1is at least 1 liter

Other:

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No prior allergic reactions to compounds of similar chemical or biological composition to study drugs
• No prior severe allergic reaction to cisplatin or carboplatin
• No insulin-dependent diabetes mellitus
• No other concurrent uncontrolled illness
• No ongoing or active infection
• No psychiatric illness or social situation that would preclude study compliance

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• At least 4 weeks since prior chemotherapy (6 weeks for mitomycin, nitrosoureas, or carmustine) and recovered

Endocrine therapy:

• See Disease Characteristics

Radiotherapy:

• See Disease Characteristics
• At least 4 weeks since prior radiotherapy and recovered
• Prior radiotherapy to the mediastinum is allowed provided LVEF is at least 45% by MUGA or echocardiogram

Surgery:

• See Disease Characteristics

Other:

• No other concurrent investigational or commercial agents for malignancy
• No concurrent combination antiretroviral therapy for HIV-positive patients