This phase III trial compares memantine to usual treatment in treating patients with primary central nervous system tumors. Memantine may block receptors (parts of nerve cells) in the brain known to contribute to a decline in cognitive function. Giving memantine may make a difference in cognitive function (attention, memory, or other thought processes) in children and adolescents receiving brain radiation therapy to treat a primary central nervous system tumors.

This phase III trial compares the effect of adding levocarnitine to standard chemotherapy vs. standard chemotherapy alone in protecting the liver in patients with leukemia or lymphoma. Asparaginase is part of the standard of care chemotherapy for the treatment of acute lymphoblastic leukemia (ALL), lymphoblastic lymphoma (LL), and mixed phenotype acute leukemia (MPAL). However, in adolescent and young adults (AYA) ages 15-39 years, liver toxicity from asparaginase is common and often prevents delivery of planned chemotherapy, thereby potentially compromising outcomes. Some groups of people may also be at higher risk for liver damage due to the presence of fat in the liver even before starting chemotherapy. Patients who are of Japanese descent, Native Hawaiian, Hispanic or Latinx may be at greater risk for liver damage from chemotherapy for this reason. Carnitine is a naturally occurring nutrient that is part of a typical diet and is also made by the body. Carnitine is necessary for metabolism and its deficiency or absence is associated with liver and other organ damage. Levocarnitine is a drug used to provide extra carnitine. Laboratory and real-world usage of the dietary supplement levocarnitine suggests its potential to prevent or reduce liver toxicity from asparaginase. The overall goal of this study is to determine whether adding levocarnitine to standard of care chemotherapy will reduce the chance of developing severe liver damage from asparaginase chemotherapy in ALL, LL and/or MPAL patients.

This phase II/III trial studies the best approach in improving quality of life and survival after a donor stem cell transplant in older, weak, or frail patients with blood diseases. Patients who have undergone a transplant often experience increases in disease and death. One approach, supportive and palliative care (SPC), focuses on relieving symptoms of stress from serious illness and care through physical, cultural, psychological, social, spiritual, and ethical aspects. While a second approach, clinical management of comorbidities (CMC) focuses on managing multiple diseases, other than cancer, such as heart or lung diseases through physical exercise, strength training, stress reduction, medication management, dietary recommendations, and education. Giving SPC, CMC, or a combination of both may work better in improving quality of life and survival after a donor stem cell transplant compared to standard of care in patients with blood diseases.