RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die.

PURPOSE: Phase I trial to study the effectiveness of suberoylanilide hydroxamic acid in treating patients who have advanced primary or metastatic solid tumors that have not responded to previous therapy.

OBJECTIVES: I. Determine the maximum tolerated dose of suberoylanilide hydroxamic acid (SAHA) in patients with refractory malignancies. II. Assess the pharmacokinetic profile of SAHA in these patients. III. Assess the biologic effects of SAHA on normal tissues and on tumor cells in these patients.

OUTLINE: This is a dose-escalation study. Patients receive suberoylanilide hydroxamic acid (SAHA) IV over 2 hours on days 1-3. Treatment repeats every 21 days for 8 courses in the absence of disease progression or unacceptable toxicity. Accelerated Phase: One patient per dose level receives escalating doses of SAHA until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which a patient experiences grade 2 or greater toxicity (other than hemoglobin anemia) with the first course or when 2 different patients experience a grade 2 toxicity (other than hemoglobin anemia) during any course of treatment. Standard Phase: Cohorts of 3-6 patients receive escalating doses of SAHA until the MTD is determined. The MTD is defined as the dose preceding that at which 2 of 6 patients experience dose-limiting toxicity.

PROJECTED ACCRUAL: Approximately 45 patients will be accrued for this study.

• Leukemia
• Lymphoma
• Multiple Myeloma and Plasma Cell Neoplasm
• Prostate Cancer
• Small Intestine Cancer
• Unspecified Adult Solid Tumor, Protocol Specific

DISEASE CHARACTERISTICS: Histologically confirmed primary or metastatic malignancy refractory to standard therapy or for which no curative therapy exists No progressive metastatic disease requiring palliative therapy within 4 weeks of study Progressive disease Increase in preexisting lesions on imaging or physical examination Patients with sole progression criterion of increased biochemical marker (e.g., carcinoembryonic antigen or CA 15-3) or increased symptoms not eligible Prostate cancer must be either progressive metastatic disease on imaging studies or have rising PSA values Minimum of 3 rising PSA values obtained at least 1 week apart, or 2 rising PSA values more than 1 month apart, with at least a 25% overall increase Serum testosterone less than 50 ng/mL Must maintain castrate status No active CNS or epidural tumor

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 70-100% Life expectancy: Not specified Hematopoietic: WBC at least 3,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 1.0 mg/dL AST no greater than 37 U/L PT no greater than 14 seconds Renal: Creatinine no greater than 2.0 mg/dL Cardiovascular: No significant cardiac disease No New York Heart Association class III or IV heart disease Pulmonary: No severe debilitating pulmonary disease Other: No infection requiring IV antibiotic treatment No other severe medical problems that would preclude study Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY: Biologic therapy: Recovered from prior biologic therapy Chemotherapy: At least 4 weeks since prior chemotherapy and recovered Endocrine therapy: Recovered from prior endocrine therapy Radiotherapy: At least 4 weeks since prior radiotherapy and recovered No concurrent radiotherapy to target lesions Surgery: Not specified Other: At least 4 weeks since other prior investigational anticancer drugs and recovered No concurrent ketoconazole in patients with prostate cancer