Meningeal relapse in a patient with acute promyelocytic leukemia: a case report and review of the literature

An unusual headache: CSF negative APML relapse in the brain

Acute Promyelocytic Leukaemia (APML) is a subtype of Acute Myeloid Leukaemia (AML), responsible for around 10% of cases of the disease in adults. Extra medullary disease (EMD) occurs infrequently in APML, but where EMD does occur, the central nervous system is one of the most commonly infiltrated sites. Our case describes a man in his 40s undergoing post-therapy surveillance for APML who presented to follow-up clinic with a headache, which was ultimately found to be caused by a tumour comprised of APML cells. His case presented a diagnostic challenge due to the benign appearances of the lesion on initial computed tomography brain imaging and the non-diagnostic cerebrospinal fluid analysis. The diagnostic difficulties described in our case emphasizes that clinicians working with APML patients must approach new neurological symptoms with a high degree of suspicion to prevent diagnostic delay.

Central Nervous System Double Relapse of Acute Promyelocytic Leukemia and Acute Myelomonocytic Leukemia

Relapse of acute promyelocytic leukemia (APL) and non-M3-acute myeloid leukemia in the central nervous system (CNS) are rare events. Here, we describe a case of simultaneous relapses of APL and acute myelomonocytic leukemia on the CNS of a patient after allogeneic bone marrow transplant. This extremely unusual case highlights the difficulties that CNS leukemia relapses pose in the post-transplant setting.

Acute promyelocytic leukemia harbouring rare FLT3-TKD and WT1 mutations: A case report

The involvement of the central nervous system (CNS) is rare in acute promyelocytic leukemia (APL). The present study reported the case of a 34-year-old male patient with APL that possessed a rare point mutation (p.Asn841Gly, c.2523C>A) in the tyrosine kinase domain of the FMS-like tyrosine kinase 3 (FLT3) gene and a novel Wilm tumor gene mutation (c.1209_1210insT/p.K404X). The patient suffered central nervous system and systemic relapses twice during systemic and intrathecal chemotherapy. At present, the patient is undergoing alternative induction and consolidation therapies, including the administration of FLT3 inhibitor, tetraarsenic tetrasulfide and novel cytotherapy, and is prepared for salvage allogeneic hematopoietic stem cell transplantion (allo-HSCT). The present study indicated that patients with APL that are at a high risk of relapse and unfavorable gene mutations should receive immediate allo-HSCT, whenever possible.

Central nervous system relapse in a patient with acute promyelocytic leukaemia: does the risk stratification matter?

Extramedullary relapse is an uncommon complication of acute promyelocytic leukaemia (APL). The most common site of extramedullary relapse is the central nervous system (CNS), and the majority of CNS relapses occur in patients with high-risk disease in which white blood cell count at presentation is greater than 10×10(3)/μL. The best management of such patients is still controversial. We describe a 47-year-old man with APL who developed two CNS relapses which were diagnosed through the presence of t(15;17)(q22;q21) on PCR of the cerebrospinal fluid (CSF), despite presenting initially with intermediate-risk disease. We conclude that the intermediate risk group is very heterogeneous and these patients sometimes may behave like high-risk patients. Also, clinicians should take into account symptoms that can be related to CNS relapse in patients with APL and consider lumbar puncture even if radiological imaging does not reveal anything.

Diagnosis of acute leukemia in cerebrospinal fluid (CSF-acute leukemia)

Cerebrospinal fluid-acute leukemia (CSF-acute leukemia) is a frequent and serious complication in patients with acute leukemia. One of the major problems of this complication is the diagnosis process itself. CSF cytology is currently considered the gold standard for establishing the diagnosis, a technique which presents various processing limitations, seriously impacting the predictive values. In the last 11 years, studies of CSF flow cytometry analysis done in patients with acute leukemia have demonstrated superiority in comparison with CSF cytology. Although comparative studies between these two techniques have been reported since 2001, no new consensus or formal changes to the gold standard have been established for the CSF acute leukemia diagnosis. The evidence suggests that positive flow cytometry cases, considered as indeterminate cases, will behave like disease in the central nervous system (CNS). Nevertheless, we think there are some variables and considerations that must be first evaluated under research protocols before CNS relapse can be established with only one positive flow cytometry analysis in the setting of indeterminate CSF samples. This paper proposes a diagnostic algorithm and complementary strategies.

Acute promyelocytic leukemia presenting with central nervous system involvement: a report of 2 cases

Central nervous system (CNS) involvement in acute promyelocytic leukemia (APL) is rare, and the presence of CNS symptoms at the time of diagnosis of APL is even rarer. We report 2 cases of APL presenting with CNS involvement. A 43-yr-old woman presented with easy bruising and stuporous mentality. Her complete blood count (CBC) revealed leukocytosis with increased blasts. Bone marrow (BM) analysis was carried out, and the diagnosis of APL was confirmed. This was done by cytogenetic analysis and demonstration of PML-RARα rearrangement by reverse transcriptase PCR in the BM cells. A lumbar puncture was performed to investigate the cause of her stuporous mentality, and her cerebrospinal fluid (CSF) analysis revealed 97% leukemic promyelocytes. Despite systemic and CNS therapy, she died due to septic shock by infection and rapid disease progression only 3 days after her admission. Another patient, a 3-yr-old girl, presented with easy bruising and epistaxis, and her CBC showed pancytopenia with increased blasts. BM studies confirmed APL. Quantitative PCR for PML-RARα in the BM cells revealed a PML-RARα/ABL ratio of 0.33 and CSF analysis revealed 9.5% leukemic promyelocytes (2 of 21 cells). She received induction chemotherapy and intrathecal therapy and achieved complete remission (CR) in the BM and CNS. She has been maintained in the CR status for the past 31 months. Thus, patients with APL must be evaluated for CNS involvement if any neurological symptoms are present at the time of diagnosis.

Central nervous system relapse in CD56+, FLT3/ITD+ promyelocytic leukemia

Central nervous system (CNS) involvement in acute promyelocytic leukemia (APL) is rare and tends to be seen mostly following treatment with all-trans retinoic acid (ATRA), due to prolonged patient survival and poor penetration of the drug in the CNS. At least 10% of extramedullary relapses in APL involve the CNS, and associated factors include an increased age, the BCR isoform, the development of differentiation syndrome, a high white cell count at presentation and hemorrhage into the CNS during induction therapy. We present the case of a patient with high-risk APL, CD56+, CD2+ in whom a CNS relapse was diagnosed through the presence of a PML/RARα rearrangement on PCR of the cerebrospinal fluid (CSF).

Long-term survival in a patient with acute promyelocytic leukemia with isolated meningeal relapse

The meningeal involvement is rare in acute promyelocytic leukemia. We experienced a 39-year-old woman who achieved complete remission with all-trans retinoic acid, idarubicin and cytarabine therapy. Several months later, she complained of non-specific headache. Her complete blood cell count was normal, but magnetic resonance image of brain revealed focal meningeal enhancement and cerebrospinal fluid showed leukemic promyelocytes and PML/RARA rearrangement. Bone marrow study showed hematologic, cytogenetic and molecular remission. She was treated with intrathecal and systemic chemotherapy and whole brain radiotherapy. The patient has survived for 68 months since the last systemic chemotherapy.

Promyelocytic sarcoma of the spine: a case report and review of the literature

Myeloid sarcoma (MS, previously named granulocytic sarcoma or chloroma) is a rare extramedullary tumour of immature myeloid cells. It can be present before, concurrently with, or after the diagnosis of acute myeloid leukemia. MS is extremely uncommon in acute promyelocytic leukemia (APL). In the case described here, MS was the sole site of APL relapse and the cause of spinal cord compression. The patient presented with neurologic symptoms due to a paravertebral mass of MS after 7 years of complete remission. He was treated with excision of the mass followed by local radiotherapy. Systemic treatment was also given with combined arsenic trioxide and all-trans retinoic acid and the patient was able to achieve a second prolonged clinical and molecular remission.

Acute promyelocytic leukemic involvement of the optic nerves following mitoxantrone treatment for multiple sclerosis

Mitoxantrone, the first immunosuppressant to receive FDA approval for treatment of worsening relapsing-remitting, secondary progressive, and progressive-relapsing multiple sclerosis (MS) is a DNA topoisomerase II inhibitor that has been associated with the development of acute promyelocytic myelogenous leukemia (APML). Central nervous system APML is a rare site of extramedullary involvement following mitoxantrone therapy. We report a patient with history of multiple sclerosis who developed bilateral optic nerve involvement as the primary manifestation of APML relapse following mitoxantrone treatment.

Extramedullary disease and targeted therapies for hematological malignancies—is the association real?

During the past years targeted therapies have gained a major role in the treatment of cancer patients, including those with hematological malignancies. Extramedullary involvement is a rare manifestation of acute and chronic leukemias and of multiple myeloma. Nevertheless, with the expanding use of targeted treatments there is an impression that the incidence of extramedullary relapses is increasing. We reviewed the reports on this phenomenon in patients treated with all-trans-retinoic acid and arsenic trioxide for acute promyelocytic leukemia, thalidomide and bortezomib for multiple myeloma and imatinib for chronic myeloid leukemia. The pathogenetic mechanisms suggested are: life prolongation by these treatments allowing for disease progression arising from dormant cells; poor penetration of the drugs to sanctuary sites like the central nervous system; the requirement of some of these drugs, especially thalidomide, for the marrow microenvironment to exert their action; and finally, a possible active role for some of the drugs, like all-trans-retinoic acid. Since the use of these targeted therapies is expanding we should be aware of this association.