Hydroxychloroquine in Treating Patients With Newly Diagnosed Chronic Graft-Versus-Host Disease

DISEASE CHARACTERISTICS: * Histologically confirmed\* newly diagnosed extensive chronic graft-versus-host disease (GVHD) of ≥ 1 organ system (e.g., lip, skin, or liver) documented by all of the following: * Clinicopathologic features of GVHD, including involvement of any of the following organ systems: * Skin changes * Oral changes * Hepatic involvement * Gastrointestinal involvement * Sicca syndrome * Pulmonary involvement * Myofascial * Skeletal * Other inflammatory conditions (e.g., myositis, arthritis, polyserositis, or unexplained pericardial, pleural, or peritoneal effusions) * Autoantibodies * Extent of disease, defined according to the following classification: * Limited chronic GVHD, defined by 1 of the following: * Localized skin involvement and/or liver dysfunction * Involvement of only 1 target organ * Extensive chronic GVHD, defined by 1 of the following: * Generalized skin involvement of ≥ 50% of body surface area * Localized skin involvement and/or liver dysfunction AND ≥ 1 of the following: * Liver histology showing chronic aggressive hepatitis, bridging necrosis, or cirrhosis * Eye involvement (Schirmer's test with \< 5 mm wetting) * Involvement of minor salivary glands or oral mucosa on lip biopsy * Involvement of any other target organs * Involvement of ≥ 2 target organs * Timing of onset, including onset of any of the following types: * Progressive onset defined as, evolving directly from acute GVHD, commonly with the development of typical manifestations such as oral or skin lichenoid changes or sclerodermatous skin changes * Quiescent onset, defined as developing after the resolution of acute GVHD * De novo onset, defined as developing with no prior history of acute GVHD * Must have ≥ 1 typical clinical manifestation of chronic GVHD that differs from that of acute GVHD (e.g., rash, anorexia, nausea, emesis, diarrhea, abdominal pain, or cholestasis) * Symptoms of acute GVHD allowed at the time of diagnosis of chronic GVHD * Prior allogeneic bone marrow, peripheral blood stem cell, or cord blood transplantation from a family member or unrelated donor for malignancy required NOTE: \*Histologic confirmation may be "consistent with GVHD" PATIENT CHARACTERISTICS: Age: * 1 to 29 Performance status: * Lansky 50-100% OR * Karnofsky 50-100% Life expectancy: * At least 2 months Hematopoietic: * Absolute neutrophil count ≥ 1,000/mm\^3, unless due to chronic GVHD (i.e., autoimmune neutropenia or bone marrow suppression) Hepatic: * See Disease Characteristics Renal: * Creatinine \< 1.5 times upper limit of normal OR * Creatinine clearance ≥ 60 mL/min Other: * Not pregnant * Negative pregnancy test * Fertile patients must use effective contraception during and for 3 months after study participation * No lysosomal storage disorder * No uncontrolled infection (e.g., persistent bacterial, fungal, or viral infection despite appropriate antimicrobial therapy) * No G6PD deficiency * No history of psoriasis or porphyria * No hypersensitivity to 4-aminoquinolines * No prior retinal or visual field changes due to 4-aminoquinolines PRIOR CONCURRENT THERAPY: Biologic therapy: * See Disease Characteristics * No concurrent daclizumab or infliximab * No concurrent thalidomide Chemotherapy: * Not specified Endocrine therapy: * Prior topical steroids for treatment of extensive chronic GVHD allowed * Prior adjustment to prednisone dose allowed if done as a reversal of a taper * Prior steroids (prednisone ≤ 1 mg/kg/day (or equivalent) for symptom management for up to 1 week before study entry allowed * Concurrent steroids for treatment and/or prophylaxis of acute GVHD allowed if prednisone dose is ≤ 2 mg/kg/day (or equivalent) * Concurrent topical steroids allowed Radiotherapy: * Not specified Surgery: * Not specified Other: * No prior treatment for extensive chronic GVHD except the following: * Topical treatment (e.g., tacrolimus ointment or pimecrolimus cream) * Adjustments of cyclosporine or tacrolimus doses for GVHD prophylaxis or treatment of acute GVHD * Concurrent cyclosporine or tacrolimus allowed * Cyclosporine must have been started before study entry * No other concurrent systemic or topical immunosuppressants, including any of the following: * Azathioprine * Mycophenolate mofetil * Psoralen-ultraviolet light therapy * Photopheresis * No administration of any of the following for 1 hour before until 2 hours after study drug administration: * Antacids * Sucralfate * Cholestyramine * Bicarbonate