RATIONALE: Dimethylxanthenone acetic acid may stop the growth of cancer cells by stopping blood flow to the tumor.

PURPOSE: Phase I trial to study the effectiveness of dimethylxanthenone acetic acid in treating patients with solid tumors that have not responded to previous therapy.

OBJECTIVES: I. Determine the toxicity of dimethylxanthenone acetic acid (DMXAA) in patients with solid tumors. II. Establish a maximum tolerated dose for this drug in these patients. III. Determine the pharmacokinetics of DMXAA in these patients. IV. Determine the effect of this regimen on coagulation parameters, TNF and other cytokine production, nitric oxide, and serotonin production in these patients. V. Assess the efficacy of this drug in this patient population. VI. Determine the effect of this drug on tumor vasculature by evaluating any changes apparent on MRI scans in these patients.

OUTLINE: This is a dose escalation, multicenter study. Patients receive dimethylxanthenone acetic acid (DMXAA) IV over 20 minutes once weekly for 6 weeks, followed by 2 weeks of rest. An additional course of therapy may be administered in the absence of unacceptable toxicity or disease progression. Cohorts of 3 patients receive escalated doses of DMXAA until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 3 patients experience dose limiting toxicity.

PROJECTED ACCRUAL: A minimum of 3 patients will be accrued to each dose level used to determine the maximum tolerated dose.

DISEASE CHARACTERISTICS: Histologically confirmed solid tumor that is not amenable to any standard therapy or is refractory to conventional therapy Tumor mass larger than 3 cm accessible to MRI scan Documented progression within the past 2 months

PATIENT CHARACTERISTICS: Age: 18 to 75 Performance status: WHO 0-2 Life expectancy: Greater than 3 months Hematopoietic: Hemoglobin at least 9 g/dL WBC at least 3,000/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin less than 1.2 mg/dL ALT less than 2 times upper limit of normal (ULN) Alkaline phosphatase less than 2 times ULN Renal: Creatinine less than 1.5 mg/dL Other: Fertile patients must use effective contraception No concurrent malignancy except cone biopsied carcinoma in situ of the cervix and adequately treated basal or squamous cell carcinoma of the skin No other serious medical condition No uncontrolled infection or serious infection within the past 28 days Must live within 1 hour of Mount Vernon Hospital, UK

PRIOR CONCURRENT THERAPY: At least 4 weeks since prior anticancer therapy (6 weeks for nitrosoureas and mitomycin) and recovered