Sequential occurrence of PTCL-NOS and T-ALL in the same patient – A rare observation suggesting possible transformation

We report here the first case of sequential occurrence of peripheral T-cell lymphoma (PTCL)-not otherwise specified and T-lineage acute lymphoblastic leukemia (T-ALL) in a 50-year-old male diagnosed with the former on lymph node biopsy. He went into complete remission with 6 cycles of etoposide-based chemotherapy; however, he presented after 8 months with fever and generalized weakness. Peripheral smear showed 90% blasts, and his total leukocyte count increased to 80,000/cu mm over the next 2 days. Flow cytometry on peripheral blood showed 84% blasts, which were CD45 bright and positive for cytoplasmic CD3, CD8, CD5, CD7, and CD1a, and negative for surface CD3, CD34, and TdT. He was diagnosed with T-ALL in a treated case of PTCL and started on induction chemotherapy, to which he responded dramatically. However, he developed neutropenic colitis on day 14 of his illness and died.