Inclusion Criteria:

- Histologically confirmed transitional cell carcinoma (TCC) of the urothelium,
including the bladder, urethra, ureter, or renal pelvis

- No pure adenocarcinomas, pure squamous cell carcinomas, small cell carcinoma, or
only small foci of TCC (less than 10% of tumor specimen)

- Locally advanced (T4b) TCC of the bladder

- Metastatic (N2 or N3 or M1)TCC of the urothelium

- HER2 expression (3+) as determined by immunohistochemistry or gene amplification
by fluorescent in situ hybridization

- Must not be a candidate for potentially curative surgery or radiotherapy

- Measurable disease

- At least 1 unidimensionally measurable lesion of at least 20 mm by conventional
techniques OR at least 10 mm by spiral CT scan

- The following lesions are considered nonmeasurable:

- Bone lesions

- Leptomeningeal disease

- Ascites

- Pleural/pericardial effusion

- Lymphangitis cutis/pulmonis

- Abdominal masses not confirmed and followed by imaging techniques

- Cystic lesions

- Primary bladder masses

- Relapsed from or failed to achieve a complete or partial response after 1 prior
systemic chemotherapy regimen for TCC, including cisplatin, carboplatin, paclitaxel,
docetaxel, or gemcitabine

- Prior adjuvant or neoadjuvant chemotherapy is considered 1 prior chemotherapy
regimen

- Prior single-agent chemotherapy as a radiosensitizer is not considered a prior
systemic chemotherapy regimen

- No known brain metastases

- Performance status - CTC 0-2

- More than 12 weeks

- Absolute neutrophil count at least 1,000/mm^3

- Platelet count at least 75,000/mm^3

- Bilirubin no greater than 2 times upper limit of normal (ULN)

- AST no greater than 2 times ULN

- Creatinine clearance at least 30 mL/min

- Ejection fraction at least 50% (or lower limit of normal) by echocardiogram or MUGA

- No history of ongoing congestive heart failure

- No active cardiac ischemia

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No other prior malignancy within the past 5 years except adequately treated basal
cell or squamous cell skin cancer or carcinoma in situ of the cervix

- HIV negative

- No known autoimmune disease

- No prior trastuzumab (Herceptin)

- At least 14 days since prior radiotherapy

- At least 30 days since prior chemotherapy

- Prior doxorubicin allowed provided cumulative dose is no greater than 300 mg/m^2

- Prior epirubicin allowed provided cumulative dose is no greater than 600 mg/m^2

- No concurrent chemotherapy

- No concurrent hormonal therapy except:

- Steroids given for adrenal failure

- Hormones administered for nondisease-related conditions (e.g., insulin for
diabetes)

- Intermittent dexamethasone as an antiemetic or for sensitivity reactions to
study drug

- No concurrent palliative radiotherapy

- Prior radiotherapy allowed provided treated area is not only site of measurable
disease

- At least 14 days since prior surgery