Central Nervous System (CNS) T-Cell Lymphoma as the Presenting Manifestation of Late-Onset Combined Immunodeficiency.

Late-onset combined immunodeficiency (LOCID), considered now a subset of common variable immunodeficiency (CVID) disorders, is characterized by a predominantly T-cell immune defect. LOCID has a distinct phenotype from CVID with a greater risk of lymphoproliferative complications. As compared to the CVID cohort, LOCID patients also have increased rates of splenomegaly and granulomatous disease. We report a case of central nervous system (CNS) T-cell lymphoma in a 67-year-old male as the presenting manifestation of LOCID. The patient achieved a complete response to therapy after 4 cycles of MATRix (methotrexate, cytarabine, and thiotepa) and 2 cycles of ICE (etoposide, carboplatin, and ifosfamide) chemotherapy followed by CNS-directed autologous stem cell transplantation. Intravenous immunoglobulin replacement was commenced to address the underlying immunodeficiency. Pulmonary lesions consistent with a diagnosis of granulomatous and lymphocytic interstitial lung disease (GLILD) were identified as a second noninfectious complication of LOCID. The pulmonary lesions resolved after chemotherapy and immunoglobulin replacement. The patient remains well with no evidence of disease recurrence now more than 18 months after completion of therapy. This is the first reported case of T-cell lymphoma in an adult patient with LOCID. Further study is needed to elucidate the mechanisms of transformation of B- or T-cells to lymphoproliferation in primary immunodeficiency patients as well as research to inform evidence-based therapeutic strategies for this challenging cohort of patients.

Prolonged administration of low-dose cytarabine and thioguanine in elderly patients with acute myeloid leukaemia (AML) achieves high complete remission rates and prolonged survival.

The prognosis of AML in elderly patients is poor and research into novel therapeutic approaches is urgently needed. This study examined the use of low-dose chemotherapy with cytarabine and thioguanine administered in repetitive cycles in 62 elderly patients with newly diagnosed or relapsed/refractory AML. The overall response rate was 58% in the total cohort. Response rates (CR/CRi) were significantly higher in patients with newly diagnosed AML (74%) compared to patients with relapsed/refractory disease (25%, p = .0004). Kaplan-Meier estimate of overall survival was 289 days (95% CI; 183-395 days) with a relapse rate of 65.7%. The induction mortality rate was 16.1% with treatment successfully undertaken in the outpatient setting. Similar clinical outcomes were observed in a retrospective analysis of a second cohort of 25 AML patients treated at a different site. These results support the use of a sustained low intensity chemotherapy approach as a therapeutic option for elderly patients with AML.