DISCUSSION;
Lymphoma is the third most common childhood malignancy accounting for 10-12% of childhood cancers. NHL account for 7% of cancers in children <20 yrs of age2 . T-LBL is the most common paediatric T cell Lymphoma. They develop in lymphoid tissues such as lymph nodes and spleen or outside of lymphoid tissues like gastrointestinal tract, liver, nasal cavity, skin etc. CML is rare in children & constitutes 2% of all leukemias in children younger than 15 years and 9% of all leukemias in adolescents between 15 and 19 years3About 90-95 percent of children with CML have a genetic alteration called the Philadelphia chromosome.
Atypical chronic myeloid leukemia, BCR-ABL1  negative (aCML) is a rare myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) in children. Currently, the diagnosis of aCML is reached primarily on morphology-based criteria. The main feature characterizing aCML is the presence of neutrophilic leucocytosis and marked dysgranulopoiesis. Moreover, to fulfil the diagnostic criteria, WBC should be ≥ 13 × 109/L with ≥ 10% of immature granulocytes, and ≤ 20% blasts in the blood and the BM 4,5. To rule out other myeloproliferative disorders, BCR-ABL1  rearrangement should be excluded in all cases6.
There has been case report of secondary malignancies in CML7 . Fu X et al9 reported simultaneous diagnosis of T-LBL and BCR-ABL positive CML in two adult patients reported which were treated with imatinib and HYPER-CVAD. Chemotherapy. Simultaneous AML and lymphoma has been reported in literature and is more frequent than simultaneous CML and lymphoma9. Melikian AL etal reported 20 adult patients with synchronous and metachronous tumors10.
Our index patient fulfilled the criteria of both T-NHL based on immunohistochemistry and typical morphology on lymph node biopsy and BCR-ABL negative CML on Bone marrow. This association, till to date, has not been previously described in literature both in adults and children. Due to rarity of this co existence, little is known about pathogenesis and optimal treatment plan.
T-NHL is an aggressive malignancy but with the development of intensified T-ALL–focused protocols has resulted in significant improvements in outcome in children 11. No standard of care is currently available for aCML management. Drugs called tyrosine kinase inhibitors (TKIs) are the first line of treatment for BCR ABL positive CML. However, the only curative treatment for atypical CML remains HSCT 12, an option available for the younger patients only. Participation on clinical trials should be considered in all cases. Different treatment options like hypomethylating agents (azacytidine or decitabine)13, Hydroxy urea. Interferon alpha, AML like therapy or targeted therapies (JAK inhibitor ruxolitinib, the SRC kinase inhibitor dasatinib, and the MEK inhibitor trametinib) have been used with variable results in patients not suitable for BMT 14,15. The prognosis of the concurrent bi-lineage malignancies is generally poorly understood and chemotherapy is necessary. More cases are required to optimize management for such children.