Beta-Glucan and Rituximab in Treating Young Patients With Relapsed or Progressive Lymphoma or Leukemia, or Lymphoproliferative Disorder Related to Donor Stem Cell Transplantation

DISEASE CHARACTERISTICS: * Histologically confirmed diagnosis of 1 of the following: * B-cell non-Hodgkin's lymphoma (NHL) * Hodgkin's lymphoma * Post-transplant lymphoproliferative disorder (PTLD) * Lymphoblastic leukemia * CD20-positive disease verified by immunophenotyping at original diagnosis, disease relapse, or disease progression * Refractory to conventional therapy, defined as 1 of the following: * Medically refractory HIV-associated NHL * Refractory or recurrent lymphoblastic leukemia * PTLD * In \> first relapse or progression of B-cell NHL or Hodgkin's lymphoma * Measurable (CT scan or MRI) or evaluable (marrow metastases or circulating lymphoblasts) disease within 4 weeks after completion of prior systemic (including systemic steroids) therapy PATIENT CHARACTERISTICS: Age * Under 22 Performance status * Not specified Life expectancy * Not specified Hematopoietic * Absolute neutrophil count \> 500/mm\^3\* * Platelet count \> 10,000/mm\^3\* NOTE: \*Excluding patients with PTLD or CD20-positive lymphoblastic leukemia Hepatic * Hepatic toxicity ≤ grade 2 Renal * Creatinine clearance ≥ 60 mL/min * Renal toxicity ≤ grade 2 Cardiovascular * Cardiac toxicity ≤ grade 2 Pulmonary * Pulmonary toxicity ≤ grade 2 Immunologic * Human anti-mouse antibody (HAMA) ≤ 1,000 units/mL * Human anti-chimeric antibody titer negative * No active, life-threatening infections except Epstein-Barr virus-associated lymphoproliferative disorder * No history…