T-cell Lymphoblastic Lymphoma

T-cell lymphoblastic lymphoma (T-LBL) is the second most common subtype of non-Hodgkin lymphoma (NHL) in children and adolescents. With current treatment, event-free survival (EFS) rates vary between 75%\~85%. Two different MTX intensification strategies are used commonly: HD-MTX with leucovorin rescue, and Capizzi-style MTX without leucovorin rescue plus PEG-ASP (C-MTX). Although superior outcome of patients with T-ALL receiving C-MTX compared with HD-MTX on the AALL0434 trial, the 2 approaches had not been compared directly in patients with T-LBL. There remains controversy on PET/CT interpretation in children with NHL. Large prospective studies in pediatric patients with T-LBL regarding PET/CT value for this is scarce. Around 1% pediatric patients with T-LBL will not achieve remission at the end of Induction (induction failure). The optimal treatment for this small subgroup is largely unclear. The BFM HR Blocks usually are applied to these patients even though the efficacy is unknown. Novel targeted therapies are needed for use. Dasatinib is identified as a targeted therapy for T-cell ALL in preclinical drug screening.

To learn if giving the study drugs calaspargase pegol-mknl and decitabine in combination with venetoclax can help to control relapsed/refractory T-ALL and T-LLy. The safety of this drug combination will also be studied.

The goal of this clinical trial is to learn if anti-CCR9 CAR T cells (which will be made using the patient's own blood cells) are safe and which dose should be used in children and adults with T cell leukaemia and lymphoma. Participants will: * have T cells collected from their blood and these T cells will be used to make the CAR-T cells in a specialized laboratory. * be admitted at the hospital a week before the CAR T cells infusion to receive a short course of chemotherapy drugs which prepare the body to receive the CAR T cells. * be given the CAR T cells into their vein. * stay in the hospital for a minimum of 2 weeks to be closely monitored * following discharge, participants will come to the clinic for check-ups (approximately 12 visits in the first two years) * during screening, treatment and follow up visits, participants will have physical examination, collection of blood samples and bone marrow biopsies and/or imaging tests (CT/PET-CT scans) depending on their type of T-cell cancer.