OBJECTIVES: I. Improve the outcome in children with first isolated central nervous system (CNS), testicular, or ocular relapse of acute lymphoblastic lymphoma (ALL), and increase the knowledge of the characteristics of extramedullary and subsequent relapses of ALL. II. Quantitate, by current molecular biologic techniques, occult systemic leukemia in cases of conventional isolated extramedullary relapse, and examine the relationship between this assessment and subsequent clinical outcome, particularly overt marrow relapse. III. Quantitate occult systemic leukemia in subsets of extramedullary relapse that include site (CNS, testis, or eye), time of relapse (early or late), initial risk group, immunophenotype, DNA index and karyotype, gender (for CNS and eye), and ethnicity, and assess the response to therapy in patients entered on companion protocol CCG-B958. IV. Compare the relative sensitivities of two quantitative in vitro assays for occult systemic leukemia (fluorescence-activated cell sorter/leukemic progenitor cell clonogenic assay vs. polymerase chain reaction-based clonospecific assay), correlate the assays with clinical outcome, and assess other biologic studies of leukemic cells (e.g., neurotropic potential in the SCID mouse xenograft model and methotrexate sensitivity). V. Determine the event-free survival (EFS) and pattern of failure in children with first isolated CNS, testicular, or ocular relapse after treatment that includes intensive systemic chemotherapy. VI. Correlate EFS in patients with CNS and ocular relapse with sex, and in patients with relapse at all three sites with ethnicity. VII. Evaluate the impact of combined chemotherapy and radiotherapy on health status in survivors at two and four years after extramedullary relapse and study entry.