RATIONALE: Sorafenib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor.

PURPOSE: This phase II trial is studying how well sorafenib works in treating patients with advanced or metastatic cancer of the urinary tract.

OBJECTIVES:

• Determine the efficacy of sorafenib, in terms of response rate and stable disease rate in patients with advanced or metastatic transitional cell carcinoma of the bladder, ureter, or renal pelvis.
• Determine the toxicity of this drug in these patients.
• Determine the response duration and time to progression in patients treated with this drug.
• Correlate baseline and post-treatment levels of pERK, pAKT, VEGFR2, CD31, Ki-67/MIB-1, and cleaved caspase 3, with clinical outcome in patients treated with this drug.

OUTLINE: This is a nonrandomized, open-label, multicenter study.

Patients receive oral sorafenib twice daily on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed within 3 weeks and then every 3 months thereafter.

PROJECTED ACCRUAL: A total of 15-33 patients will be accrued for this study within 8-16 months.

Ages Eligible for Study:  18 Years and above,  Genders Eligible for Study:  Both

Criteria

DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed transitional cell carcinoma of the bladder, ureter, or renal pelvis
• Advanced or metastatic disease
• Measurable disease, defined as ≥ 1 unidimensionally measurable lesion ≥ 20 mm by conventional techniques OR ≥ 10 mm by spiral CT scan
• The following are not considered measurable disease:
• Bone lesions
• Leptomeningeal disease
• Ascites
• Pleural/pericardial effusion
• Inflammatory breast disease
• Lymphangitis cutis/pulmonis
• Abdominal masses not confirmed and followed by imaging techniques
• Cystic lesions
• Tumor accessible for biopsy
• No known brain metastases

PATIENT CHARACTERISTICS: Age

• 18 and over

Performance status

• ECOG 0-1 OR
• Karnofsky 70-100%

Life expectancy

• More than 3 months

Hematopoietic

• WBC ≥ 3,000/mm^3
• Absolute neutrophil count ≥ 1,500/mm^3
• Platelet count ≥ 100,000/mm^3
• No bleeding diathesis

Hepatic

• Bilirubin normal
• AST and ALT ≤ 2.5 times upper limit of normal (ULN)

Renal

• Creatinine < 1.5 times ULN OR
• Creatinine clearance ≥ 45 mL/min

Cardiovascular

• No myocardial infarction within the past 6 months
• No congestive heart failure
• No unstable angina pectoris
• No active cardiomyopathy
• No unstable ventricular arrhythmia
• No other cardiac arrhythmia
• No uncontrolled hypertension

Gastrointestinal

• No active peptic ulcer disease
• No malabsorption syndrome
• No gastrointestinal (GI) tract disease that would preclude ability to take oral medication
• No uncontrolled inflammatory GI disease (e.g., Crohn''''s disease or ulcerative colitis)
• No requirement for IV alimentation
• Able to swallow and retain oral medication

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No ongoing or active serious infection
• No uncontrolled psychotic disorders
• No psychiatric illness or social situation that would preclude study compliance
• No other active malignancy within the past 5 years except adequately treated carcinoma in situ or nonmelanoma skin cancer
• No history of allergic reaction attributed to compounds of similar chemical or biological composition to sorafenib
• No other uncontrolled illness
• No other serious medical condition that would preclude study treatment

PRIOR CONCURRENT THERAPY: Biologic therapy

• Not specified

Chemotherapy

• At least 4 weeks since prior chemotherapy (including adjuvant or neoadjuvant chemotherapy)
• At least 6 weeks for nitrosoureas or mitomycin

Endocrine therapy

• Not specified

Radiotherapy

• More than 4 weeks since prior radiotherapy
• No concurrent radiotherapy to the sole site of measurable disease

Surgery

• No prior surgical procedures affecting absorption

Other

• No prior systemic therapy for advanced or metastatic disease
• At least 7 days since prior and no concurrent administration of any of the following:
• Rifampin
• Phenytoin
• Carbamazepine
• Phenobarbital
• Hypericum perforatum (St. John''''s wort)
• No other concurrent investigational agents
• No other concurrent anticancer therapy
• No concurrent therapeutic anticoagulation
• Concurrent prophylactic anticoagulation (i.e., low-dose warfarin) allowed provided requirements for PT, INR, or PTT are met
• No concurrent combination anti-retroviral therapy for HIV-positive patients