Dasatinib in Treating Patients With Locally Advanced or Metastatic Mucosal Melanoma, Acral Melanoma, or Vulvovaginal Melanoma That Cannot Be Removed By Surgery

OBJECTIVES:

Primary

- To estimate the objective tumor response rate in patients with KIT-positive,
unresectable, locally advanced or metastatic acral or mucosal melanoma treated with
dasatinib monotherapy.

Secondary

- To estimate the response duration in patients treated with this drug.

- To estimate the progression-free survival of patients treated with this drug.

- To evaluate the safety profile of this drug in these patients.

- To evaluate the PDGFR expression and activation of Src family kinases in tumor samples
and correlate these parameters with response to treatment.

OUTLINE: This is a multicenter study.

Patients receive oral dasatinib twice daily on days 1-21. Courses repeat every 21 days in the
absence of disease progression or unacceptable toxicity.

Tissue samples may be collected from some patients for correlative studies.

After completion of study therapy, patients are followed up periodically for up to 5 years.

DISEASE CHARACTERISTICS:

- Histologically or cytologically confirmed melanoma of 1 of the following subtypes:

- Acral melanoma (defined as occurring on the palms, soles, or subungual sites)

- Melanoma arising from the vagina and/or vulva

- Melanoma arising on other mucosal surface (not vagina or vulva)

- Unresectable locally advanced or metastatic disease

- c-KIT mutation identified by polymerase chain reaction (PCR) and sequencing meeting 1
of the following criteria:

- At least 1 mutation in exon 9, 11, 13, 17, or 18

- At least 1 mutation in an exon not listed above

- Metastatic tumor blocks are required for the evaluation of KIT mutations or
amplifications

- Measurable disease, defined as at least one measurable lesion by RECIST criteria

- Prior radiotherapy to a measurable lesion allowed provided there is radiographic
evidence of progression of that lesion

- No ocular melanoma

- Baseline bone scan required for patients with known bone metastases, elevated alkaline
phosphatase, or symptoms raising suspicion of bone metastases

- History or clinical evidence of brain metastasis allowed provided the following
criteria are met:

- Completed radiotherapy or surgical treatment of brain lesions AND there is no
evidence of CNS progression for ≥ 8 weeks

- Must not require corticosteroids for treatment of cerebral edema from brain
metastases

PATIENT CHARACTERISTICS:

- ECOG performance status 0-1

- WBC ≥ 3,000/mm³

- Absolute granulocyte count ≥ 1,500/mm³

- Platelet count ≥ 100,000/mm³

- Creatinine ≤ 2.0 times upper limit of normal (ULN) OR creatinine clearance ≥ 40 mL/min

- Total bilirubin ≤ 1.5 times ULN (< 3.0 times ULN in the presence of Gilbert disease)

- AST and ALT ≤ 2.5 times ULN (≤ 5.0 times ULN in the presence of liver metastases)

- Serum potassium and magnesium normal (repletion allowed)

- Total serum calcium or ionized calcium normal

- INR ≤ 1.5 and PTT normal

- Therapeutic anticoagulation with warfarin allowed provided INR ≤ 1.5 or PTT
normal prior to initiating anticoagulation therapy

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No evidence of bleeding diathesis

- No other malignancies except basal cell or squamous cell skin cancer, carcinoma in
situ of the cervix, ductal or lobular carcinoma in situ of the breast, or other
malignancies from which the patient has been continuously disease-free for ≥ 5 years

- Patients must not have any clinically significant cardiovascular disease including the
following:

- Myocardial infarction or ventricular tachyarrhythmia within 6 months

- Prolonged QTc >480 msec (Fridericia correction)

- Ejection fraction less than institutional normal

- Major conduction abnormality (unless a cardiac pacemaker is present)

- Patients with any cardiopulmonary symptoms of unknown cause (e.g., shortness of
breath, chest pain, etc.) are to be evaluated by a baseline echocardiogram with
or without stress test as needed in addition to electrocardiogram (EKG) to rule
out QTc prolongation

- Patients with underlying cardiopulmonary dysfunction are excluded from the study

- No uncontrolled hypertension, defined as systolic blood pressure ≥ 150 mm Hg or
diastolic blood pressure ≥ 90 mm Hg

- Hypertension that is adequately controlled with medication allowed

- No QTc prolongation, defined as a QTc interval ≥ 450 msecs

- No concurrent serious illness including, but not limited to, ongoing or active
infection requiring parenteral antibiotics

- No psychiatric illness or social situation that would limit compliance with study
requirements

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- Recovered from prior therapy

- No prior treatment with targeted therapies directed to C-KIT/PDGFR (e.g., imatinib
mesylate or sunitinib malate)

- Prior limb perfusion allowed

- Prior systemic therapy allowed

- At least 4 weeks since prior chemotherapy or immunotherapy

- Prior adjuvant or neoadjuvant chemotherapy or immunotherapy allowed

- At least 4 weeks since prior radiotherapy

- No concurrent cytochrome P450 enzyme-inducing antiepileptic drugs (i.e., phenytoin,
carbamazepine, or phenobarbital), rifampin, or Hypericum perforatum (St. John wort)