Patient description: The patient is a 16-year-old girl recently diagnosed with myasthenia gravis, class IIa. She complains of diplopia and weakness affecting in her upper extremities. She had a positive anti-AChR antibody test, and her single fiber electromyography (SFEMG) was positive. She is on acetylcholinesterase inhibitor treatment combined with immunosuppressants. But she still has some symptoms. She does not smoke or use illicit drugs. She is not sexually active, and her menses are regular. Her physical exam and lab studies are not remarkable for any other abnormalities. BP: 110/75 Hgb: 11 g/dl WBC: 8000 /mm3 Plt: 300000 /ml Creatinine: 0.5 mg/dl BUN: 10 mg/dl Beta hcg: negative for pregnancy

Clinical trial eligibility criteria: eligible ages (years): 3.0-75.0,  Accelerated Phase Chronic Myelogenous Leukemia Acute Myeloid Leukemia With Multilineage Dysplasia Following Myelodysplastic Syndrome Adult Acute Lymphoblastic Leukemia in Remission Adult Acute Myeloid Leukemia in Remission Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities Adult Acute Myeloid Leukemia With Del(5q) Adult Acute Myeloid Leukemia With Inv(16)(p13;q22) Adult Acute Myeloid Leukemia With t(15;17)(q22;q12) Adult Acute Myeloid Leukemia With t(16;16)(p13;q22) Adult Acute Myeloid Leukemia With t(8;21)(q22;q22) Adult Nasal Type Extranodal NK/T-cell Lymphoma Anaplastic Large Cell Lymphoma Angioimmunoblastic T-cell Lymphoma Aplastic Anemia Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative Childhood Acute Lymphoblastic Leukemia in Remission Childhood Acute Myeloid Leukemia in Remission Childhood Chronic Myelogenous Leukemia Childhood Diffuse Large Cell Lymphoma Childhood Immunoblastic Large Cell Lymphoma Childhood Myelodysplastic Syndromes Childhood Nasal Type Extranodal NK/T-cell Lymphoma Chronic Eosinophilic Leukemia Chronic Myelomonocytic Leukemia Chronic Neutrophilic Leukemia Chronic Phase Chronic Myelogenous Leukemia de Novo Myelodysplastic Syndromes Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue Fanconi Anemia Juvenile Myelomonocytic Leukemia Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable Nodal Marginal Zone B-cell Lymphoma Noncontiguous Stage II Adult Burkitt Lymphoma Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma Noncontiguous Stage II Adult Diffuse Mixed Cell Lymphoma Noncontiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma Noncontiguous Stage II Adult Immunoblastic Large Cell Lymphoma Noncontiguous Stage II Adult Lymphoblastic Lymphoma Noncontiguous Stage II Grade 1 Follicular Lymphoma Noncontiguous Stage II Grade 2 Follicular Lymphoma Noncontiguous Stage II Grade 3 Follicular Lymphoma Noncontiguous Stage II Mantle Cell Lymphoma Noncontiguous Stage II Marginal Zone Lymphoma Noncontiguous Stage II Small Lymphocytic Lymphoma Paroxysmal Nocturnal Hemoglobinuria Previously Treated Myelodysplastic Syndromes Primary Myelofibrosis Recurrent Adult Acute Lymphoblastic Leukemia Recurrent Adult Acute Myeloid Leukemia Recurrent Adult Burkitt Lymphoma Recurrent Adult Diffuse Large Cell Lymphoma Recurrent Adult Diffuse Mixed Cell Lymphoma Recurrent Adult Diffuse Small Cleaved Cell Lymphoma Recurrent Adult Grade III Lymphomatoid Granulomatosis Recurrent Adult Hodgkin Lymphoma Recurrent Adult Immunoblastic Large Cell Lymphoma Recurrent Adult Lymphoblastic Lymphoma Recurrent Adult T-cell Leukemia/Lymphoma Recurrent Childhood Acute Lymphoblastic Leukemia Recurrent Childhood Acute Myeloid Leukemia Recurrent Childhood Anaplastic Large Cell Lymphoma Recurrent Childhood Grade III Lymphomatoid Granulomatosis Recurrent Childhood Large Cell Lymphoma Recurrent Childhood Lymphoblastic Lymphoma Recurrent Childhood Small Noncleaved Cell Lymphoma Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma Recurrent Grade 1 Follicular Lymphoma Recurrent Grade 2 Follicular Lymphoma Recurrent Grade 3 Follicular Lymphoma Recurrent Mantle Cell Lymphoma Recurrent Marginal Zone Lymphoma Recurrent Mycosis Fungoides/Sezary Syndrome Recurrent Small Lymphocytic Lymphoma Recurrent/Refractory Childhood Hodgkin Lymphoma Refractory Chronic Lymphocytic Leukemia Refractory Multiple Myeloma Relapsing Chronic Myelogenous Leukemia Secondary Acute Myeloid Leukemia Secondary Myelodysplastic Syndromes Splenic Marginal Zone Lymphoma Stage III Adult Diffuse Small Cleaved Cell Lymphoma Stage III Adult Immunoblastic Large Cell Lymphoma Stage III Adult Lymphoblastic Lymphoma Stage III Grade 1 Follicular Lymphoma Stage III Grade 2 Follicular Lymphoma Stage III Grade 3 Follicular Lymphoma Stage III Mantle Cell Lymphoma Stage III Marginal Zone Lymphoma Stage III Small Lymphocytic Lymphoma Stage IV Adult Burkitt Lymphoma Stage IV Adult Diffuse Small Cleaved Cell Lymphoma Stage IV Adult Immunoblastic Large Cell Lymphoma Stage IV Adult Lymphoblastic Lymphoma Stage IV Grade 1 Follicular Lymphoma Stage IV Grade 2 Follicular Lymphoma Stage IV Grade 3 Follicular Lymphoma Stage IV Mantle Cell Lymphoma Stage IV Marginal Zone Lymphoma Stage IV Small Lymphocytic Lymphoma Waldenström Macroglobulinemia Diagnosis of a histology documented hematologic malignancy or marrow disorder Bone marrow failure disorders and other non-malignant hematologic or immunologic disorders Acquired bone marrow failure disorders aplastic anemia, paroxysmal nocturnal hemoglobinuria (PNH) Primary allogeneic hematopoietic stem cell transplantation (HSCT) is appropriate for selected patients with severe aplastic anemia; however, patients with aplastic anemia must have failed at least one cycle of standard immunosuppressive therapy with calcineurin inhibitor plus anti-thymocyte globulin (ATG) if a fully-matched donor is not available Patients with PNH must have a history of thrombosis related to PNH Hereditary bone marrow failure disorders Fanconi anemia or related chromosomal breakage syndrome dyskeratosis congenita, Diamond-Blackfan anemia, Shwachman-Diamond syndrome, Kostmann syndrome, congenital amegakaryocytic thrombocytopenia Fanconi anemia or related chromosomal breakage syndrome: positive chromosome breakage analysis using diepoxybutane (DEB) or mitomycin C if applicable Dyskeratosis: diagnosis is supported by using either telomerase reverse transcriptase (TERC) gene mutation in autosomal dominant Dyskeratosis Congenita or Xlinked DKC1 gene mutation Other non-malignant hematologic or immunologic disorders that require transplantation Quantitative or qualitative congenital platelet disorders (including but not limited to congenital amegakaryocytopenia, absent-radii syndrome, Glanzmann's thrombasthenia)  Uncontrolled central nervous system (CNS) disease (for hematologic malignancies) Karnofsky (adult) or Lansky (for =< 16 years) performance status =< 50% Diffusing capacity of the lung for carbon monoxide (DLCO) less than 40% predicted, corrected for hemoglobin (Hb) and/or alveolar ventilation Cardiac: left ventricular ejection fraction less than 40% Bilirubin >= 3 x upper limit of normal Liver alkaline phosphatase >= 3 x upper limit of normal Serum glutamic oxaloacetic transaminase (SGOT) or serum glutamic pyruvate transaminase (SGPT) >= 3 x upper limit of normal Child's class B and C liver failure Calculated creatinine clearance < 40 cc/min by the modified Cockcroft-Gault formula for adults or the Schwartz formula for pediatrics Patients who have received maximally allowed doses (given in 2 Gy fractions, or equivalent) of previous radiation therapy to various organs as follows