Arsenic Trioxide Plus Vitamin C in Treating Patients With Recurrent or Refractory Multiple Myeloma

DISEASE CHARACTERISTICS: Histologically confirmed multiple myeloma M-protein by serum protein electrophoresis or urine protein electrophoresis Quantitative determination of immunoglobulin Bone marrow biopsy and aspirate with a plasma cell count greater than 10% Refractory or chemoresistant disease defined as failure to respond (less than 50% reduction in M protein level) or progression within 2 months after receiving at least 2 chemotherapy regimens including: Alkylating based regimen (melphalan) in combination with steroids (prednisone) or other chemotherapy regimens (e.g., vincristine, bleomycin, melphalan, cyclophosphamide, and prednisone or vincristine, carmustine, doxorubicin, and prednisone) Vincristine, doxorubicin, and dexamethasone (VAD) regimen Pulse therapy with high dose steroids alone High dose alkylating agent and autologous stem cell transplantation Allogeneic bone marrow transplantation Plateau phase defined as M protein in the serum or urine for more than 6 weeks despite response to prior therapy Must have received at least 2 of the chemotherapy regimens listed above or equivalent regimens Recurrent disease defined as progression more than 2 months after initial therapy and failure to respond (less than 50% reduction or progression in M protein levels) to 1 chemotherapy regimen listed above or other salvage regimens (e.g., high-dose cyclophosphamide or topotecan) Must have received VAD or other equivalent chemotherapy regimen Should be considered for autologous or allogenic transplantation Prior local radiotherapy allowed PATIENT CHARACTERISTICS: Age: Over 18 Performance status: Karnofsky 60-100% Life expectancy: Not specified Hematopoietic: WBC at least 2,000/mm^3* Platelet count at least 50,000/mm^3* NOTE: *Unless attributable to bone marrow infiltration by multiple myeloma Hepatic: Bilirubin less than 3 mg/dL Transaminases less than 2.5 times upper limit of normal (ULN) Renal: Creatinine less than 1.5 times ULN OR Creatinine clearance at least 60 mL/min Cardiovascular: No cardiac arrhythmias including recurrent supraventricular arrhythmia, any type of sustained ventricular arrhythmia, or conduction block (atrioventricular block grade II or III, left bundle branch block) Ejection fraction at least 30% No uncontrolled ischemic heart disease Other: Not pregnant or nursing Negative pregnancy test Fertile patients must use effective barrier contraception during and for 4 months after study HIV negative No grade 3 or higher neurological disorder, including seizure disorders No underlying medical condition that would preclude study No other active malignancy except adequately treated basal or squamous cell carcinoma of the skin or carcinoma in situ of the cervix PRIOR CONCURRENT THERAPY: Biologic therapy: See Disease Characteristics Chemotherapy: See Disease Characteristics At least 2 weeks since prior chemotherapy Endocrine therapy: See Disease Characteristics Concurrent steroid treatment allowed except for primary treatment of myeloma Radiotherapy: See Disease Characteristics Concurrent local radiotherapy for pain or symptom control allowed provided the pain or symptom is not related to disease progression Surgery: Not specified Other: No other concurrent ascorbic acid supplements No other concurrent investigational drug or therapy Concurrent bisphosphonates allowed