0794GCC: Pentamidine in Treating Patients With Relapsed or Refractory Melanoma

DISEASE CHARACTERISTICS:

Histologically confirmed melanoma

Relapsed or refractory disease
Tumor expresses wild-type p53
Measurable S100B by immunohistochemistry
Measurable disease, defined as at least one lesion that can be accurately measured in at least one dimension (longest diameter to be recorded) as ≥ 20 mm by conventional techniques or as ≥ 10 mm by spiral CT scan
Tumor amenable to biopsy
Must have been evaluated for potentially curative resection

No unstable or symptomatic brain metastases (e.g., seizures, headache related to tumor, or presence of neurologic deficits attributable to tumor)

Patients with stable brain metastases (by CT scan or MRI) are eligible provided they were treated with local therapy > 4 weeks ago AND do not require maintenance steroid treatment

PATIENT CHARACTERISTICS:

Eastern Cooperative Oncology Group (ECOG) performance status 0-2
Life expectancy > 12 weeks
White Blood Cell count (WBC) ≥ 3,000/mcL
Absolute Neutrophil Count (ANC) ≥ 1,500/mcL
Platelet count ≥ 80,000/mcL
Hemoglobin ≥ 8 g/dL
Total bilirubin ≤ 1.5 times normal
aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 times upper limit of normal
Creatinine ≤ 1.5 times normal or creatinine clearance ≥ 60 mL/min
Not pregnant or nursing
Fertile patients must use effective contraception during and for ≥ 3 months after completion of study treatment
Able to take oral medications on a regular basis
No history of allergic reactions attributed to pentamidine
Mean Corrected QT Interval (QTc) ≤ 470 msec (with Bazett's correction) on screening ECG
No history of familial long QT syndrome
Proteinuria ≤ 1 on two consecutive dipsticks taken ≥ 1 week apart

No concurrent uncontrolled illness including, but not limited to, any of the following:

Hypertension
Ongoing or active infection
Symptomatic congestive heart failure
Unstable angina pectoris
Renal failure
Cardiac arrhythmia
Psychiatric illness/social situations that would limit compliance with study requirements

PRIOR CONCURRENT THERAPY:

Recovered from all prior therapy
Any number of prior chemotherapy regimens allowed
More than 4 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin C)
More than 4 weeks since prior radiotherapy or major surgery
More than 30 days since prior participation in an investigational trial
No concurrent medication that may markedly affect renal function (e.g., vancomycin, amphotericin, zoledronic acid)
No concurrent combination antiretroviral therapy for HIV-positive patients
No other concurrent investigational agents