Rare non-Hodgkin lymphoma of childhood and adolescence: A consensus diagnostic and therapeutic approach to pediatric-type follicular lymphoma, marginal zone lymphoma, and nonanaplastic peripheral T-cell lymphoma.

Pediatric-type follicular (PTFL), marginal zone (MZL), and peripheral T-cell lymphoma (PTCL) account each for <2% of childhood non-Hodgkin lymphoma. We present clinical and histopathological features of PTFL, MZL, and few subtypes of PTCL and provide treatment recommendations. For localized PTFL and MZL, watchful waiting after complete resection is the therapy of choice. For PTCL, therapy is subtype-dependent and ranges from a block-like anaplastic large cell lymphoma (ALCL)-derived and, alternatively, leukemia-derived therapy in PTCL not otherwise specified and subcutaneous panniculitis-like T-cell lymphoma to a block-like mature B-NHL-derived or, preferentially, ALCL-derived treatment followed by hematopoietic stem cell transplantation in first remission in hepatosplenic and angioimmunoblastic T-cell lymphoma.

Can folate replacement induce lymphoma progression?

A 43-year-old Japanese man with a low haemoglobin level of 1.3 g/dL and multiorgan dysfunction syndrome (MODS) was admitted to our hospital. He was diagnosed with folate deficiency, which was initially attributed to his malnutrition. He was transfused with several units of packed red blood cells and treated with folate, thiamine and vitamin B12 supplements; he showed a prompt haematological response and recovery from MODS. However, 3 weeks after the initial recovery, he had a relapse of pancytopenia and developed high-grade fever along with rapidly enlarging, generalised lymphadenopathy. Bone marrow biopsy revealed hemophagocytosis, and lymph node biopsy revealed peripheral T-cell lymphoma, not otherwise specified. Folate supplementation may have promoted lymphoma progression.

Preemptive leucovorin administration minimizes pralatrexate toxicity without sacrificing efficacy.

Balancing efficacy and safety of drugs is key for successful cancer therapy, as adverse reactions can prohibit the use of efficacious treatments. Pralatrexate (PDX) is a novel antifolate with a higher affinity for tumor cells than methotrexate, Food and Drug Administration (FDA) approved for use in relapsed and refractory peripheral T-cell lymphoma (PTCL) and transformed mycosis fungoides (T-MF). Patients with T-MF have a higher incidence of adverse events than patients with other lymphomas, necessitating a lower recommended dose of 15 mg/m(2) (vs. 30 mg/m(2) for PTCL). Dose-limiting toxicity (DLT) mucositis occurs in about 25% of patients with T-MF, but milder mucositis is observed in almost all patients with T-MF, frequently leading to therapy discontinuation despite clinical response. Leucovorin rescue is the standard of care for high-dose methotrexate therapy, but has not been studied or recommended for use with PDX. We report our clinical experience using leucovorin with PDX (30 mg/m(2)) with good clinical response and no DLTs. Prophylactic leucovorin deserves further investigation in prospective clinical trials to allow patients with cutaneous lymphomas to receive the full benefit of PDX therapy without intolerable toxicity.