Central Nervous System Involvement in Adults with Acute Leukemia: Diagnosis, Prevention, and Management

Treatment of a Patient with Acute Promyelocytic Leukemia with Multiple Isolated Relapses in the Central Nervous System: A Case Report and Mini-Review of the Literature

The efficacy of therapeutics for acute promyelocytic leukemia (APL) has exhibited an increase in recent years. Only a few patients experience relapse, including extramedullary relapse, and in patients with extramedullary relapse, the central nervous system (CNS) is the most common site. To date, there is no expert consensus or clinical guidelines available for CNS relapse, at least to the best of our knowledge. The optimal therapeutic strategy and management options for these patients remain unclear. The present study reports the treatment of a patient with APL with multiple isolated relapses in the CNS. In addition, through a mini-review of the literature, the present study provides a summary of various reports of this disease and discusses possible treatment options for these patients.

Nuanced Management of a Skull Base Tumor in the Setting of Relapsed Acute Lymphoblastic Leukemia

Introduction  Relapsed acute lymphoblastic leukemia (ALL) involving the central nervous system (CNS) is a significant issue that contributes to both morbidity and mortality. Given the poor outcomes in patients with CNS relapse, understanding how ALL involving intracranial relapse presents and is treated is critical. Here, we present a complex case of relapsed recurrent ALL in a pediatric patient. Case Report  An 11-year-old patient presented with double relapse of ALL in the form of an extensive skull base lesion and again with leptomeningeal disease. For the skull base lesion, she was treated nonsurgically with chemotherapy and radiation, which led to a remarkable reduction in the size of the lesion. However, she was found to have early recurrence with leptomeningeal enhancement resulting in hydrocephalus 5 months after completing therapy. A shunt was placed successfully. Currently, she is being managed with monthly intrathecal chemotherapy with cerebrospinal fluid sampling and bone marrow biopsies every 2 months. Discussion  We report the significant effect of chemotherapy and radiotherapy in reducing the size of the extensive skull base lesion, saving the patient from the risks associated with surgery. This patient's initial relapse, with a large skull base lesion that had intracranial involvement, is an unusual presentation of relapsed ALL. The additional early recurrence of leptomeningeal disease further makes this case unique and the management even more nuanced. Here, we demonstrate a multidisciplinary approach for the successful treatment of our patient, which can help guide the management of similar patients in the future.

Therapeutic drug monitoring of imatinib - how far are we in the leukemia setting?

INTRODUCTION

Tyrosine kinase inhibitors (TKIs) have revolutionized survival rates of chronic myeloid leukemia (CML) and Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) and replaced hematopoietic stem cell transplantation (hSCT) as the key treatment option for these patients. More recently, the so-called Philadelphia chromosome-like (Ph-like) ALL has similarly benefitted from TKIs. However, many patients shift from the first generation TKI, imatinib, due to treatment-related toxicities or lack of treatment efficacy. A more personalized approach to TKI treatment could counteract these challenges and potentially be more cost-effective. Therapeutic drug monitoring (TDM) has led to higher response rates and less treatment-related toxicity in adult CML but is rarely used in ALL or in childhood CML.

AREAS COVERED

This review summarizes different antileukemic treatment indications for TKIs with focus on imatinib and its pharmacokinetic/-dynamic properties as well as opportunities and pitfalls of TDM for imatinib treatment in relation to pharmacogenetics and co-medication for pediatric and adult Ph+/Ph-like leukemias.

EXPERT OPINION

TDM of imatinib adds value to standard monitoring of ABL-class leukemia by uncovering non-adherence and potentially mitigating adverse effects. Clinically implementable pharmacokinetic/-dynamic models adjusted for relevant pharmacogenetics could improve individual dosing. Prospective trials of TDM-based treatments, including both children and adults, are needed.

Spinal Cord Neoplasms

OBJECTIVE

This article discusses the diagnostic approach to patients with suspected neoplasms of the spinal cord and reviews the most common primary and metastatic spinal neoplasms and their presentations.

LATEST DEVELOPMENTS

Neoplasms of the spinal cord are rare entities that can involve the spinal cord parenchyma, the dura and leptomeninges, or the extradural space. The most common intramedullary spinal cord neoplasms are primary spinal cord tumors, including ependymomas, pilocytic astrocytomas, and diffuse midline gliomas. The most common primary neoplasms of the spine are intradural extramedullary spinal meningiomas, whereas primary neoplasms of the leptomeninges are rare. Advances in molecular characterization of spinal cord tumors and recent clinical trials of these rare entities are expanding the repertoire of systemic therapy options for primary spinal cord neoplasms. Metastases to the spine most often affect the extradural space. Metastatic epidural spinal cord compression is a neurologic emergency that requires a rapid, multidisciplinary response to preserve neurologic function.

ESSENTIAL POINTS

Neurologists should understand the diagnostic approach to neoplasms of the spinal cord. Knowledge of the most common spinal cord neoplasms will allow for appropriate management and optimal patient care.

Craniospinal irradiation for CNS leukemia: rates of response and durability of CNS control

PURPOSE

Management of CNS involvement in leukemia may include craniospinal irradiation (CSI), though data on CSI efficacy are limited.

METHODS

We retrospectively reviewed leukemia patients who underwent CSI at our institution between 2009 and 2021 for CNS involvement. CNS local recurrence (CNS-LR), any recurrence, progression-free survival (PFS), CNS PFS, and overall survival (OS) were estimated.

RESULTS

Of thirty-nine eligible patients treated with CSI, most were male (59%) and treated as young adults (median 31 years). The median dose was 18 Gy to the brain and 12 Gy to the spine. Twenty-five (64%) patients received CSI immediately prior to allogeneic hematopoietic cell transplant, of which 21 (84%) underwent total body irradiation conditioning (median 12 Gy). Among 15 patients with CSF-positive disease immediately prior to CSI, all 14 assessed patients had pathologic clearance of blasts (CNS-response rate 100%) at a median of 23 days from CSI start. With a median follow-up of 48 months among survivors, 2-year PFS and OS were 32% (95% CI 18-48%) and 43% (95% CI 27-58%), respectively. Only 5 CNS relapses were noted (2-year CNS-LR 14% (95% CI 5-28%)), which occurred either concurrently or after a systemic relapse. Only systemic relapse after CSI was associated with higher risk of CNS-LR on univariate analysis. No grade 3 or higher acute toxicity was seen during CSI.

CONCLUSION

CSI is a well-tolerated and effective treatment option for patients with CNS leukemia. Control of systemic disease after CSI may be important for CNS local control. CNS recurrence may reflect reseeding from the systemic space.

Multi-institutional analysis of outcomes in acute myeloid leukemia patients with central nervous system involvement

We evaluated outcomes of AML patients with central nervous system (CNS) involvement at two academic institutions. Fifty-two adult patients were identified. Neurologic symptoms were reported in 69% of patients, with headache the most common (33%). 84% (n = 42) of patients cleared their cerebrospinal fluid (CSF), with a median number of one dose of intrathecal (IT) chemotherapy. Of these patients, 21% (n = 9) had a CSF relapse, with 67% (n = 6) of those experiencing CSF relapse also having concurrent bone marrow relapse. Of the 36 patients with baseline neurologic symptoms, 69% had improvement in symptoms post-IT therapy. The median overall survival was 9.3 months and 3.5 months for patients with CNS involvement diagnosed before/during induction and at relapse, respectively. In this study, IT therapy was rapidly effective in clearing CSF blasts and improving neurologic symptoms in most patients. Few patients experienced CSF relapse, which predominantly occurred in the setting of concomitant bone marrow relapse.

Exclusion of Acute Myeloid Leukemia Patients with Central Nervous System Involvement from Clinical Trials: An Analysis of the National Institutes of Health Clinical Trials Registry from 2012 to 2022

INTRODUCTION

Central nervous system (CNS) involvement in acute myeloid leukemia (AML) can be successfully treated with intrathecal chemotherapy and carries debatable prognostic impact. However, patients with CNS involvement are commonly excluded from clinical trials at an unknown rate. We systematically evaluated exclusion criteria of AML clinical trials based on CNS involvement and determined associations with clinical trial characteristics.

METHODS

The National Institutes of Health Clinical Trials Registry was searched for interventional adult AML trials between 2012 and 2022 that were phase 1, 2, or 3 and relevant trial characteristics were extracted.

RESULTS

1,270 trials were included in the analysis with 790 trials (62.1%) explicitly excluding CNS involvement. There was no significant change in rates of CNS exclusion over the past decade. CNS exclusion was higher in trials that included the non-transplant population compared to trials exclusive to the transplant population (66.9% vs. 43.8%, p < 0.01). Non-transplant trials were also more likely to exclude patients with a history of or ambiguous timing of CNS involvement (p < 0.01). Phase 3 trials were associated with more liberal definitions of CNS exclusion (history or ambiguous timing) as compared to phase 1 and 2 trials that had higher rates of excluding patients with only active CNS involvement (p < 0.01).

CONCLUSION

A majority of AML clinical trials, particularly in the non-transplant setting, exclude patients with CNS involvement. Many of these trials, most notably phase 3 trials, exclude patients not only with active but also with any history of CNS involvement. Further research is needed to determine optimal management of these patients in order to increase representation in large clinical trials.

Intrathecal chemotherapy for the management of lymphoblastic lymphoma in a 4-year-old dog: a case report

Intrathecal chemotherapy is used in human medicine for the treatment or prophylaxis of CNS hematopoietic neoplasia. However, the clinical benefits in veterinary medicine have been scarcely documented. A 4-year-old male entire cross-breed dog presented with a 24-h history of severe lethargy, pelvic limb weakness, and urinary retention. Examination revealed generalized peripheral lymphadenomegaly, and the neurological findings were suggestive of a myelopathy in the region of T3-L3. Following the diagnosis of multicentric lymphoblastic B-cell lymphoma (stage Vb), a modified L-LOP with cytosine arabinoside was started, and complete clinical remission was achieved. After 4 weeks, there was acute neurological deterioration (spinal pain and proprioceptive deficits) without peripheral lymphadenomegaly. MRI findings and CSF analysis were consistent with meningeal and spinal cord lymphoma infiltration at the level of L3. Intrathecal chemotherapy (cytosine arabinoside and methotrexate) were administered in the cisterna magna with systemic dexamethasone and analgesia. Clinical signs were resolved within 24 h, and the patient remained asymptomatic for 3.5 weeks. After this period, CNS relapse (proprioceptive deficits and severe thoracolumbar pain) was suspected, and repeat intrathecal chemotherapy was declined. The patient was humanely euthanized 9 weeks after the initial diagnosis. This is the first report on the clinical benefit of intrathecal chemotherapy with a combination of methotrexate and cytarabine for the management of CNS lymphoma in dogs. Based on our case, intrathecal chemotherapy with methotrexate and cytarabine can induce a short-lasting CNS clinical remission (3 weeks).

Diagnosis and management of adult central nervous system leukemia

Central nervous system leukemia (CNSL) is a prominent infiltration reason for therapy failing in acute leukemia. Recurrence rates and the prognosis have alleviated with current prophylactic regimens. However, the accurate stratification of relapse risk and treatment regimens for relapsed or refractory patients remain clinical challenges yet to be solved. Recently, with hematopoietic stem cell transplantation (HSCT) and chimeric antigen receptor-T (CAR-T) cellular therapy showing encouraging effects in some CNSL patients, advances in treating CNSL have already been reported. The development of molecular targeted agents as well as antibody-based drugs will provide patients with more personalized treatment. This article summarized recent research developments about risk factors, diagnosis, prevention, and treatment in adults with CNSL.

Optimizing Management of the Central Nervous System in Patients with Acute Lymphoblastic Leukemia Undergoing Allogeneic Stem Cell Transplantation

Purpose

To evaluate clinical outcomes and patterns of failure, specifically in regards to the central nervous system (CNS), in patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (HSCT) using total body irradiation (TBI)-based conditioning regimens.

Methods and Materials

All adult patients (aged ≥18 years) with ALL undergoing allogeneic HSCT using TBI-based conditioning regimens treated from 1995 to 2020 at Duke University Medical Center were evaluated. Various patient, disease, and treatment-related factors were collected, including CNS prophylaxis and treatment interventions. Clinical outcomes, including freedom from CNS relapse, were calculated using the Kaplan-Meier method for patients with and without CNS disease at presentation.

Results

One hundred and fifteen patients with ALL were included the analysis (myeloablative, 110; nonmyeloablative, 5). Of the 110 patients undergoing a myeloablative regimen, most (n = 100) did not have CNS disease before transplant. For this subgroup, peritransplant intrathecal chemotherapy was administered in 76% (median of 4 cycles) and 10 received a radiation boost to the CNS (cranial irradiation, 5; craniospinal, 5). Only 4 failed in the CNS after transplant, none of whom received a CNS boost, with freedom from CNS relapse at 5 years of 95% (95% confidence interval (CI), 84-98%). Freedom from CNS relapse was not improved with a radiation therapy boost to the CNS (100% vs 94%, P = .59). Overall survival, leukemia-free survival, and nonrelapse mortality at 5 years were 50%, 42%, and 36%, respectively. Among the 10 patients with CNS disease before transplant, 10 of 10 received intrathecal chemotherapy and 7 received a radiation boost to the CNS (cranial irradiation, 1; craniospinal, 6) and none subsequently failed in the CNS. A nonmyeloablative HSCT was pursued for 5 patients because of advanced age or comorbidities. None of these patients had prior CNS disease or received a CNS or testicular boost, and none failed in the CNS after transplant.

Conclusions

A CNS boost may not be necessary in patients with high-risk ALL without CNS disease undergoing a myeloablative HSCT using a TBI-based regimen. Favorable outcomes were observed with a low-dose craniospinal boost in patients with CNS disease.

Cerebrospinal fluid interleukin-6 is a potential diagnostic biomarker for central nervous system involvement in adult acute myeloid leukemia

Objective

We evaluated the correlation between cerebrospinal fluid (CSF) cytokine levels and central nervous system (CNS) involvement in adult acute myeloid leukemia (AML).

Methods

The study sample consisted of 90 patients diagnosed with AML and 20 with unrelated CNS involvement. The AML group was divided into two sub-groups: those with (CNS+, n=30) and without CNS involvement (CNS-, n=60). We used a cytometric bead assay to measure CSF interleukin (IL)-2, IL-4, IL-6, and IL-10, tumor necrosis factor-α, interferon-γ, and IL-17A. We used receiver operating characteristic curves to evaluate the ability of CSF cytokine levels to identify CNS involvement in adult AML.

Results

CSF IL-6 levels were significantly higher in CNS+adult AML patients and positively correlated with the lactate dehydrogenase levels (r=0.738, p&lt;0.001) and white blood cell (WBC) count (r=0.455, p=0.012) in the blood, and the protein (r=0.686, p&lt;0.001) as well as WBC count in the CSF (r=0.427, p=0.019). Using a CSF IL-6 cut-off value of 8.27 pg/ml yielded a diagnostic sensitivity and specificity was 80.00% and 88.46%, respectively (AUC, 0.8923; 95% CI, 0.8168–0.9678). After treating a subset of tested patients, their CSF IL-6 levels decreased. Consequently, the elevated CSF IL-6 levels remaining in CNS+ adult AML patients post-treatment were associated with disease progression.

Conclusion

CSF IL-6 is a promising marker for the diagnosis of adult AML with CNS involvement and a crucial dynamic indicator for therapeutic response.

Case report: Intravitreal methotrexate in intraocular acute lymphoblastic leukemia

Direct leukemic infiltration of the eye is most frequently associated with acute lymphoblastic leukemia (ALL), probably due to its well-known central nervous system (CNS) tropism. Systemic treatment alone may not be sufficient for intraocular leukemia. Data on local treatment are scarce. Here, we present two cases of intraocular ALL treated with intravitreal methotrexate (MTX). Initially, anatomical improvement and visual stability were observed. The first patient experienced anatomical and visual worsening after a year of treatment. Treatment was withheld after 2 months for the second patient due to poor systemic conditions. Corneal toxicity and intraocular pressure elevation were observed in the first case. In both cases, eye involvement was associated with CNS or systemic relapse. This highlights the importance of incorporating ocular disease management in a comprehensive approach to therapy. Our experience corroborates previous findings on MTX injections as an effective and safe therapeutic option for intraocular leukemia. Further evidence is needed to consolidate the use of intravitreal MTX to treat such a debilitating localization of leukemia.

Metabolomic profiling of cerebrospinal fluid reveals an early diagnostic model for central nervous system involvement in acute lymphoblastic leukaemia

The pathogenesis of central nervous system involvement (CNSI) in patients with acute lymphoblastic leukaemia (ALL) remains unclear and a robust biomarker of early diagnosis is missing. An untargeted cerebrospinal fluid (CSF) metabolomics analysis was performed to identify independent risk biomarkers that could diagnose CNSI at the early stage. Thirty-three significantly altered metabolites between ALL patients with and without CNSI were identified, and a CNSI evaluation score (CES) was constructed to predict the risk of CNSI based on three independent risk factors (8-hydroxyguanosine, l-phenylalanine and hypoxanthine). This predictive model could diagnose CNSI with positive prediction values of 95.9% and 85.6% in the training and validation sets respectively. Moreover, CES score increased with the elevated level of central nervous system (CNSI) involvement. In addition, we validated this model by tracking the changes in CES at different stages of CNSI, including before CNSI and during CNSI, and in remission after CNSI. The CES showed good ability to predict the progress of CNSI. Finally, we constructed a nomogram to predict the risk of CNSI in clinical practice, which performed well compared with observed probability. This unique CSF metabolomics study may help us understand the pathogenesis of CNSI, diagnose CNSI at the early stage, and sequentially achieve personalized precision treatment.

Prognostic significance of CNSL at diagnosis of childhood B-cell acute lymphoblastic leukemia: A report from the South China Children's Leukemia Group

OBJECTIVES

The prognostic significance of acute lymphoblastic leukemia (ALL) patients with central nervous system leukemia (CNSL) at diagnosis is controversial. We aimed to determine the impact of CNSL at diagnosis on the clinical outcomes of childhood B-cell ALL in the South China Children's Leukemia Group (SCCLG).

METHODS

A total of 1,872 childhood patients were recruited for the study between October 2016 and July 2021. The diagnosis of CNSL depends on primary cytological examination of cerebrospinal fluid, clinical manifestations, and imaging manifestations. Patients with CNSL at diagnosis received two additional courses of intrathecal triple injections during induction.

RESULTS

The frequency of CNLS at the diagnosis of B-cell ALL was 3.6%. Patients with CNSL at diagnosis had a significantly higher mean presenting leukocyte count (P = 0.002) and poorer treatment response (P <0.05) compared with non-CNSL patients. Moreover, CNSL status was associated with worse 3-year event-free survival (P = 0.030) and a higher risk of 3-year cumulative incidence of relapse (P = 0.008), while no impact was observed on 3-year overall survival (P = 0.837). Multivariate analysis revealed that CNSL status at diagnosis was an independent predictor with a higher cumulative incidence of relapse (hazard ratio = 2.809, P = 0.016).

CONCLUSION

CNSL status remains an adverse prognostic factor in childhood B-cell ALL, indicating that additional augmentation of CNS-directed therapy is warranted for patients with CNSL at diagnosis.