Isolated central nervous system lymphoid blast crisis in chronic myeloid leukaemia in major molecular remission

Leukostasis With Isolated Central Nervous System Involvement in Chronic Phase of Chronic Myelogenous Leukemia

Chronic myelogenous leukemia (CML) is a hematologic malignancy with unique significance to the field of hematology and oncology, specifically due to the development of tyrosine kinase inhibitors (TKIs). CML often presents with nonspecific symptoms, and the quality of life in patients with CML has drastically improved as a result of TKIs. However, complications of CML including the risk of transforming into life-threatening blast crises continue to exist. Further, as most patients are asymptomatic in the chronic phase, patients often present with serious complications associated with noncompliance to TKIs. For example, central nervous system (CNS) manifestations of CML have been reported, both as the initial presentation of undiagnosed CML and as known complication of uncontrolled CML. Hyperleukocytosis is a manifestation of uncontrolled CML and leukostasis is a complication, occurring in cases of acute myeloid leukemia (AML). Here we present a rare case of leukostasis in a patient with known CML presenting on computed tomography (CT) as intracranial masses in the chronic phase. Our goal is to discuss this rare case of leukostasis in adult CML and describe its management.

Isolated CNS Blast Crises in Chronic Myeloid Leukaemia Presenting as Hypertrophic Pachymeningitis and Bilateral Optic Neuritis: A Case Report

Extramedullary blast crises of Chronic Myeloid Leukaemia (CML) involving CNS is rare and usually accompanies systemic relapse. Isolated CNS blast relapse is an extremely uncommon event. A 35-year-old male was diagnosed with chronic phase (CP) CML two years back at our hospital and was started on imatinib 400 mg daily. Patient achieved haematological and cytogenetic remission at three and 12 months respectively but was non-compliant with medications thereafter. He presented to our emergency with headache and bilateral visual loss. CNS examination revealed neck rigidity and fundoscopy revealed disc edema with retinal vein dilatation and haemorrhages. Cerebrospinal fluid (CSF) analysis revealed lymphocytic pleocytosis and a positive cytospin for myeloid blasts. MRI brain suggested pachymeningeal enhancement involving falx cerebri and tentorium along with bilateral optic nerve thickening. Patient maintained cytogenetic remission at current presentation. A diagnosis of isolated CNS blast crises with pachymeningitis and bilateral optic nerve involvement was made and two doses of intrathecal chemotherapy were administered. However, patient died due to a rapidly downhill course. A previously unreported finding of pachymeningitis with bilateral optic neuritis has been highlighted in this case, along with a brief review of this rare condition.

Isolated central nervous system relapse in chronic myeloid leukemia

Chronic myeloid leukemia is a myeloproliferative disorder that has three distinguished phases: chronic, accelerated, and blastic. In extremely rare cases, the blast phase can affect the central nervous system without concomitant bone marrow involvement. We report the case of a patient with chronic myeloid leukemia who, despite having achieved complete cytogenetic remission in the bone marrow for several years, experienced a blast crisis of the central nervous system following an episode of infectious meningoencephalitis.

Dasatinib maintenance therapy after allogeneic hematopoietic stem cell transplantation for an isolated central nervous system blast crisis in chronic myelogenous leukemia

A 22-year-old male with Ph-positive chronic myelogenous leukemia (CML) was started on treatment with imatinib. After 12 months of therapy, he achieved a complete cytogenetic response (CCyR). Although the CCyR persisted in his bone marrow, he developed an isolated CML blast crisis in his central nervous system (CNS) after 29 months of therapy. He underwent allogeneic hematopoietic stem cell transplantation (HSCT) following combination therapy with dasatinib, intrathecal chemotherapy and cranial irradiation. Subsequently, 168 days after allogeneic HSCT, he was started on dasatinib maintenance therapy to prevent a CNS relapse. Thirty-eight months after allogeneic HSCT, he has sustained a complete molecular response in both bone marrow and CNS. We believe dasatinib has the potential to prevent CNS relapse if used for maintenance therapy after allogeneic HSCT.