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