Trastuzumab in Treating Patients With Previously Treated, Locally Advanced, or Metastatic Cancer of the Urothelium

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