Green Tea Extract in Treating Patients With Stage 0, Stage I, or Stage II Chronic Lymphocytic Leukemia

DISEASE CHARACTERISTICS: Confirmed diagnosis of chronic lymphocytic leukemia (CLL) Stage 0, I, or II disease Previously untreated disease Splenomegaly, hepatomegaly, or lymphadenopathy are not required for the diagnosis of CLL Absolute lymphocyte count > 10,000/mm^3 Lymphocytosis must consist of small to moderate size lymphocytes, with ≤ 55% prolymphocytes, atypical lymphocytes, or lymphoblasts morphologically Phenotypically characterized B-CLL defined by all of the following criteria: A population of leukemic cells that co-expresses the B-cell antigen CD23 as well as CD5 in the absence of other T-cell markers (CD3, CD2, etc.) Dim surface immunoglobulin expression Exclusively κ or λ light chains Mantle cell lymphoma must be excluded by demonstrating the absence of the t(11:14) by FISH testing Patients who require chemotherapy for treatment of CLL, based on any of the following criteria, are excluded: CLL-related symptoms requiring treatment, including any of the following: Unintentional weight loss ≥ 10% body weight within the previous 6 months Extreme fatigue Fevers > 100.5°F for 2 weeks without evidence of infection Night sweats without evidence of infection Evidence of progressive marrow failure due to CLL involvement of bone marrow as manifested by the development of worsening anemia (hemoglobin < 11 g/dl) and/or thrombocytopenia (platelet count < 100,000/mm^3) Thrombocytopenia due to immune phenomena (ITP) is permitted as long as platelet count is ≥ 100,000/mm^3and the patient is not on active pharmacologic therapy Massive (i.e. > 6 cm below left costal margin) or progressive splenomegaly Massive nodes or clusters (i.e., > 10 cm in longest diameter) or progressive adenopathy Progressive lymphocytosis with an increase of > 50% over 2 month period, or an anticipated lymphocyte doubling time of < 6 months PATIENT CHARACTERISTICS: Platelet count ≥ 100,000/µL ANC ≥ 1500/µL Hemoglobin ≥ 11 g/dL Total or direct bilirubin ≤ 1.5 x upper limit of normal (ULN) AST (SGOT) and ALT (SGPT) ≤ 2 x ULN Creatinine ≤ 1.5 x ULN OR creatinine clearance ≥ 40 mL/min May have a history of autoimmune hemolytic anemia (AIHA) and positive Coombs test provided there has not been active hemolysis requiring transfusion or steroid treatment ≤ 10 weeks prior to registration ECOG performance status 0, 1, or 2 Life expectancy of ≥ 6 months No uncontrolled infection No myocardial infarction within the past 6 weeks No New York Heart Association class III or IV congestive heart failure Not pregnant or nursing Negative pregnancy test Must employ adequate contraception (condoms, diaphragm, birth control pills, injections, intrauterine device [IUD], or abstinence, etc.) prior to study entry and for the duration of study participation No other severe medical or psychiatric illness No active hemolysis requiring transfusion or other pharmacologic therapy PRIOR CONCURRENT THERAPY: At least 8 weeks since prior and no other concurrent over the counter green tea or green tea extract No prior daily use of over the counter green tea products for medicinal purposes for > 4 weeks (phase II only) No other concurrent chemotherapy, immunotherapy, radiotherapy, or any ancillary therapy considered investigational (utilized for a non-FDA-approved indication and in the context of a research investigation) No concurrent combination anti-retroviral therapy for HIV positive patients No concurrent oral steroid preparations