Sunitinib Malate or Valproic Acid in Preventing Metastasis in Patients With High-Risk Uveal Melanoma

Inclusion Criteria: * Age \>= 18 years old * Histologically-confirmed primary uveal melanoma * Definitive local treatment for primary tumor, including surgical resection (enucleation) or radiation therapy (radioactive plaque or external proton beam) * High risk for distal recurrence defined as any of the following conditions: A) Confirmed both monosomy 3 and 8q amplification; B) Class II tumor * Less than 6 months from the date that local treatment (surgical or radiation) of the primary tumor was finalized * Karnofsky performance status (PS) scores of 70 or greater * If female, no pregnancy * If of child-bearing potential (\< one year post-menopausal), must agree to practice an effective method of avoiding pregnancy (including oral or implanted contraceptives, intrauterine device, condom, diaphragm with spermicidal, cervical cap, abstinence or sterile sex partner) from the time informed consent is signed (women only) or the time of initiation of sunitinib (sunitinib malate) (men only); both men and women must agree to continue using such precautions while receiving sunitinib or valproic acid and for 30 days after the final dose * Absolute neutrophil count (ANC) \>= 1500/mm\^3 * Platelets \>= 100,000/mm\^3 * Hemoglobin \>= 8 g/dl * Serum creatinine \< 1.5 times upper limit of normal range (ULN) or creatinine clearance \>= 40 ml/min * Serum bilirubin \< 1.5 times ULN * Serum albumin \> 2.0 g/dl * Adequate cardiac function (ejection fraction \[EF\] \> 50%) based on multi gated …