Incidence, risk factors and management of pleural effusions during dasatinib treatment in unselected elderly patients with chronic myelogenous leukaemia

Fluid retention-associated adverse events in patients treated with BCR::ABL1 inhibitors based on FDA Adverse Event Reporting System (FAERS): a retrospective pharmacovigilance study

OBJECTIVES

This study aimed to conduct a thorough analysis of fluid retention-associated adverse events (AEs) associated with BCR::ABL inhibitors.

DESIGN

A retrospective pharmacovigilance study.

SETTING

Food and Drug Administration Adverse Event Reporting System (FAERS) database for BCR::ABL inhibitors was searched from 1 January 2004 to 30 September 2021.

MAIN OUTCOME MEASURES

Reporting OR (ROR) and 95% CI were used to detect the signals. ROR was calculated by dividing the odds of fluid retention event reporting for the target drug by the odds of fluid retention event reporting for all other drugs. The signal was considered positive if the lower limit of 95% CI of ROR was >1. The analysis was run only considering coupled fluid retention events/BCR::ABL inhibitors with at least three cases.

RESULTS

A total of 97 823 reports were identified in FAERS. Imatinib had the most fluid retention signals, followed by dasatinib and nilotinib, while bosutinib and ponatinib had fewer signals. Periorbital oedema (ROR=24.931, 95% CI 22.404 to 27.743), chylothorax (ROR=161.427, 95% CI 125.835 to 207.085), nipple swelling (ROR=48.796, 95% CI 26.270 to 90.636), chylothorax (ROR=35.798, 95% CI 14.791 to 86.642) and gallbladder oedema (ROR=77.996, 95% CI 38.286 to 158.893) were the strongest signals detected for imatinib, dasatinib, nilotinib, bosutinib and ponatinib, respectively. Pleural effusion, pericardial effusion and pulmonary oedema were detected for all BCR::ABL inhibitors, with dasatinib having the highest RORs for pleural effusion (ROR=37.424, 95% CI 35.715 to 39.216), pericardial effusion (ROR=14.146, 95% CI 12.649 to 15.819) and pulmonary oedema (ROR=11.217, 95% CI 10.303 to 12.213). Patients aged ≥65 years using dasatinib, imatinib, nilotinib or bosutinib had higher RORs for pleural effusion, pericardial effusion and pulmonary oedema. Patients aged ≥65 years and females using imatinib had higher RORs for periorbital oedema, generalised oedema and face oedema.

CONCLUSIONS

This pharmacovigilance study serves as a clinical reminder to physicians to be more vigilant for fluid retention-associated AEs with BCR::ABL inhibitors.

Adverse reactions after treatment with dasatinib in chronic myeloid leukemia: Characteristics, potential mechanisms, and clinical management strategies

Dasatinib, a second-generation tyrosine kinase inhibitor, is recommended as first-line treatment for patients newly diagnosed with chronic myeloid leukemia (CML) and second-line treatment for those who are resistant or intolerant to therapy with imatinib. Dasatinib is superior to imatinib in terms of clinical response; however, the potential pulmonary toxicities associated with dasatinib, such as pulmonary arterial hypertension and pleural effusion, may limit its clinical use. Appropriate management of dasatinib-related severe events is important for improving the quality of life and prognosis of patients with CML. This review summarizes current knowledge regarding the characteristics, potential mechanisms, and clinical management of adverse reactions occurring after treatment of CML with dasatinib.

Non-Coding RNAs Are Implicit in Chronic Myeloid Leukemia Therapy Resistance

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm initiated by the presence of the fusion gene BCR::ABL1. The development of tyrosine kinase inhibitors (TKIs) highly specific to p210^BCR-ABL1, the constitutively active tyrosine kinase encoded by BCR::ABL1, has greatly improved the prognosis for CML patients. Now, the survival rate of CML nearly parallels that of age matched controls. However, therapy resistance remains a persistent problem in the pursuit of a cure. TKI resistance can be attributed to both BCR::ABL1 dependent and independent mechanisms. Recently, the role of non-coding RNAs (ncRNAs) has been increasingly explored due to their frequent dysregulation in a variety of malignancies. Specifically, microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs) have been shown to contribute to the development and progression of therapy resistance in CML. Since each ncRNA exhibits multiple functions and is capable of controlling gene expression, they exert their effect on CML resistance through a diverse set of mechanisms and pathways. In most cases ncRNAs with tumor suppressing functions are silenced in CML, while those with oncogenic properties are overexpressed. Here, we discuss the relevance of many aberrantly expressed ncRNAs and their effect on therapy resistance in CML.

Dasatinib-Induced Bilateral Pleural Effusions

Fluid accumulation in the form of pleural effusions and ascites may be attributed to a single etiology. Diagnosis depends on a thorough clinical history as well as fluid analysis. We present the case of a 60-year-old man with chronic myeloid leukemia (CML) on dasatinib, recent right-sided ischemic stroke, alcohol-associated liver disease, cocaine and alcohol use disorders in early remission, and hypertension who presented with subacute-onset of bilateral pleural effusions and ascites. Pleural fluid analysis showed an exudative effusion, while ascitic fluid analysis showed a transudative collection. After an extensive workup, the bilateral effusions were attributed to dasatinib therapy, which was also suspected to play an unclear role in the worsening ascites. Although peripheral edema and pleural effusions are well-recognized and common side effects of tyrosine kinase inhibitors (TKIs), this case represents the first description of a patient presenting with bilateral TKI-induced pleural effusions as well as concomitant ascites of unclear origin.

Pericardial Effusion Secondary to Nilotinib in an Elderly Patient With Chronic Myelogenous Leukemia

Tyrosine kinase inhibitors (TKIs) are the first-line treatment for patients with chronic myelogenous leukemia (CML). Serositis, including pleural and pericardial effusions, is a frequent adverse event with some TKIs while less frequent with others. We present a case of a 76-year-old woman with CML on nilotinib who presented with progressive fatigue and was eventually found to have cardiac tamponade from a large pericardial effusion attributed to nilotinib. The patient required urgent therapeutic pericardiocentesis and switching of TKIs from nilotinib to bosutinib. 

A narrative review on adverse effects of dasatinib with a focus on pharmacotherapy of dasatinib-induced pulmonary toxicities

Chronic myeloid leukemia (CML), a myeloproliferative disorder caused by the over activity of BCR-ABL1 (breakpoint cluster region-Abelson), has been successfully treated by Tyrosine kinase inhibitors (TKIs). While imatinib is known as the first-line treatment of CML, in some cases other TKIs including dasatinib, nilotinib, bosutinib, and ponatinib may be preferred. Dasatinib, a second-generation TKI, inhibits multiple family kinases including BCR-ABL, SRC family kinases, receptor kinases, and TEC family kinases. It is effective against most imatinib-resistant cases except T315I mutation. Despite the superiority of dasatinib in its hematologic and cytogenetic responses in CML compared to imatinib, its potentially harmful pulmonary complications including pleural effusion (PE) and pulmonary arterial hypertension (PAH) may limit its use. Appropriate management of these serious adverse reactions is critical in both improving the quality of life and the outcome of the patient. In this narrative review, we will scrutinize the pulmonary complications of dasatinib and focus on the management of these toxicities.

Dasatinib-Induced Pleural and Pericardial Effusions

Chronic myeloid leukemia (CML) is a myeloproliferative disease associated with the Philadelphia chromosome and BCR-ABL1 fusion gene. Tyrosine kinase inhibitors (TKI) are now the standard therapy for this condition. Among the approved TKIs for CML is dasatinib. We present a case of a 58-year-old Egyptian male who developed bilateral pleural (grade II) as well as pericardial effusions (grade II) secondary to dasatinib 100 mg once-daily dosing. He was managed by interrupting dasatinib and introducing diuretics and steroids. The objective is to raise awareness about this unfavorable effect as it may affect the patient's quality of life and increase rates of treatment withdrawal.

The Hidden Variable: A Case of Dasatinib-Induced Respiratory Failure

Tyrosine kinase inhibitors that target the BCR/ABL mutation have been used as therapies of BCR/ABL positive acute lymphoblastic leukemia (ALL) with significant results. Dasatinib is a multitargeted tyrosine kinase inhibitor with significant activity in Philadephia positive ALL which is resistant to imatinib, as well as in treatment-naïve patients. We present a case of an elderly patient with Philadelphia chromosome-positive ALL, who presented with acute hypoxic respiratory failure in the setting of active immunotherapy with dasatinib.

Dasatinib-induced chylothorax: report of a case and review of the literature

Dasatinib is a tyrosine kinase inhibitor for the treatment of BCR-ABL-positive chronic myeloid leukaemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukaemia (ALL). Although fluid retention is a common adverse event associated with dasatinib, chylothorax is exceptionally rare. The pathological mechanism, clinical manifestation and management of dasatinib-induced chylothorax are completely unclear. A 71-year-old man treated with dasatinib for CML was admitted for progressive dyspnea. Computed tomography (CT) showed a pleural effusion that was more prominent on the right thoracic cavity. Thoracentesis showed thick milky pleural fluid, which was then confirmed as chylothorax by chylum qualitative tests and triglyceride measurements. Radionuclide lymphoscintigraphy yielded an obstruction at the end segment of the thoracic duct, but no leakage points were found. After excluding common causes, drug-induced chylothorax was presumed. Then, dasatinib was withdrawn, and 1 week later, chylothorax resolved. To further elucidate the relationship between the medication and chylothorax, dasatinib was resumed tentatively for 2 days. As expected, pleural effusion recurred soon. Based on these clinical manifestations, the diagnosis of dasatinib-induced chylothorax was identified. The patient was suggested to stop dasatinib and use an alternative drug as recommended by the haematologist. Pleural effusion is the common adverse reaction of dasatinib, but chylothorax is rare. Only six cases of dasatinib-induced chylothorax have been reported, and our patient is the seventh case. Once a patient with dasatinib treatment develops chylothorax, dasatinib should be considered one of the possible causes. If no other definitive aetiological factor is identified, dasatinib discontinuation might be the optimum scheme.

Comparative Safety and Health Care Expenditures Among Patients With Chronic Myeloid Leukemia Initiating First-Line Imatinib, Dasatinib, or Nilotinib

PURPOSE

Tyrosine kinase inhibitors (TKIs) have dramatically improved survival for patients with chronic myeloid leukemia (CML). No overall survival differences were observed between patients initiating first- and second-generation TKIs in trials; however, real-world safety and cost outcomes are unclear. We evaluated comparative safety and health care expenditures between first-line imatinib, dasatinib, and nilotinib among patients with CML.

PATIENTS AND METHODS

Eligible patients had one or more fills for imatinib, dasatinib, or nilotinib in the MarketScan Commercial and Medicare Supplemental databases between January 1, 2011, and December 31, 2016 (earliest fill is the index date), 6 months pre-index continuous enrollment, CML diagnosis, and no TKI use in the pre-index period. Hospitalizations or emergency department visits (safety events) were compared across treatment groups using propensity-score-weighted 1-year relative risks (RRs) and subdistribution hazard ratios (HRs). Inflation-adjusted annual health care expenditures were compared using quantile regression.

RESULTS

Eligible patients included 1,417 receiving imatinib, 1,067 receiving dasatinib, and 647 receiving nilotinib. The 1-year risk of safety events was high: imatinib, 37%; dasatinib, 44%; and nilotinib, 40%, with higher risks among patients receiving dasatinib (RR, 1.17; 95% CI, 1.06 to 1.30) and nilotinib (RR, 1.07; 95% CI, 0.93 to 1.23) compared with those receiving imatinib. Over a median of 1.7 years, the cumulative incidence of safety events was higher among patients receiving dasatinib (HR, 1.23; 95% CI, 1.10 to 1.38) and nilotinib (HR, 1.08; 95% CI, 0.95 to 1.24) than among those receiving imatinib. One-year health care expenditures were high (median, $125,987) and were significantly higher among patients initiating second-generation TKIs compared with those receiving imatinib (difference in medians: dasatinib v imatinib, $22,393; 95% CI, $17,068 to $27,718; nilotinib v imatinib, $19,463; 95% CI, $14,689 to $24,236).

CONCLUSION

Patients receiving imatinib had the lowest risk of hospitalization or emergency department visits and 1-year health care expenditures. Given a lack of significant differences in overall survival, imatinib may represent the ideal first-line therapy for patients, on average.

Complications and Toxicities Associated with Cancer Therapies in the Intensive Care Unit

Advances in the management of hematologic malignancies and solid tumors have given rise to diverse modalities to treat cancer other than cytotoxic chemotherapy, including targeted therapies, immunotherapies, and cellular therapies. Currently, there are over 175 FDA-approved antineoplastic agents in the United States, many with a diverse and profound toxicity profile. Complications of antineoplastic therapy may result in the need for intensive care unit (ICU) admission to provide acute symptom management. Accordingly, ICU providers caring for cancer patients should have a working knowledge of the toxicities and complications associated with antineoplastic therapy.

Discontinuation of tyrosine kinase inhibitors in CML patients in real-world clinical practice at a single institution

BACKGROUND

Most patients with chronic myeloid leukemia (CML) treated with tyrosine kinase inhibitors (TKIs) will relapse if treatment is withdrawn, but various trials have recently demonstrated that a significant proportion of patients who achieved a stable and deep molecular response (DMR) can stop therapy without relapsing. However, most information on treatment cessation was obtained from clinical trials with strict recruiting criteria.

METHODS

We evaluated the outcome of 25 patients with CML that discontinued TKI therapy in our institute in real-world clinical practice.

RESULTS

Of the 25 patients, 76% discontinued therapy in sustained deep molecular response (SDMR) and 24% were in unsustained DMR (UDMR). Discontinuation of therapy due to adverse effects was observed in 5 and 50% of the patients in the SDMR and UDMR groups, respectively. After TKI discontinuation, patients were followed for a median of 24 months. At the time of this analysis, 56% patients had a molecular relapse after a median of 4 months. SDMR and longer treatment duration were associated with lower probability of molecular relapse: 25% in SDMR patients with TKI treatment > 96 months and 85% in UDMR patients with TKI treatment ≤96 months. All relapsed patients promptly resumed TKI therapy and regained at least major molecular response (MMR).

CONCLUSIONS

Our results suggest that TKI discontinuation is safe outside clinical trials and particularly effective in CML patients who are in SDMR with longer TKI treatment duration.

Plasma concentrations of dasatinib have a clinical impact on the frequency of dasatinib dose reduction and interruption in chronic myeloid leukemia: an analysis of the DARIA 01 study

Background

Dasatinib has shown promising anti-leukemic activity against chronic myeloid leukemia (CML). However, patients receiving dasatinib frequently require dose reductions and treatment interruptions (treatment alteration).

Methods

We prospectively analyzed the frequency and significance of treatment alteration during dasatinib therapy in patients with CML. In all patients, trough plasma concentrations of dasatinib (C_min) at steady state were assessed on day 28 of therapy.

Results

28% of patients had their doses reduced at a median of 42 days, and 25% of patients had temporarily interrupted at a median of 54 days after treatment initiation. The overall dasatinib treatment alteration-free rate at 1 year was 66%. Age was significantly correlated with C_min on day 28 (p = 0.014), and the correlation remained significant after adjusting dasatinib dose (g), body weight (kg) (C_min/D/W) (p = 0.026). In the univariate analysis, deep molecular response, advanced PS, higher C_min/D/W were associated with a significantly higher risk of treatment alteration (HR 4.19, 95% CI: 1.06–16.60, p = 0.041; HR 5.26, 95% CI: 1.33–20.80, p = 0.018; and HR 10.15, 95% CI: 2.55–40.48, p = 0.001, respectively). In the multivariate analysis, advanced PS and higher C_min/D/W were correlated with the incidence of treatment alteration (HR 4.78, 95% CI: 1.01–22.70, p = 0.049; HR 6.17, 95% CI: 1.17–32.50, respectively).

Conclusion

Current data demonstrate that patients treated with dasatinib who displayed a high C_min/D/W value and/or advanced PS were at a high risk for altered treatment.

Rho-Kinase Inhibition Ameliorates Dasatinib-Induced Endothelial Dysfunction and Pulmonary Hypertension

The multi-kinase inhibitor dasatinib is used for treatment of imatinib-resistant chronic myeloid leukemia, but is prone to induce microvascular dysfunction. In lung this can manifest as capillary leakage with pleural effusion, pulmonary edema or even pulmonary arterial hypertension. To understand how dasatinib causes endothelial dysfunction we examined the effects of clinically relevant concentrations of dasatinib on both human pulmonary arterial macro- and microvascular endothelial cells (ECs). The effects of dasatinib was compared to imatinib and nilotinib, two other clinically used BCR/Abl kinase inhibitors that do not inhibit Src. Real three-dimensional morphology and high resolution stiffness mapping revealed softening of both macro- and microvascular ECs upon dasatinib treatment, which was not observed in response to imatinib. In a dose-dependent manner, dasatinib decreased transendothelial electrical resistance/impedance and caused a permeability increase as well as disruption of tight adherens junctions in both cell types. In isolated perfused and ventilated rat lungs, dasatinib increased mean pulmonary arterial pressure, which was accompanied by a gain in lung weight. The Rho-kinase inhibitor Y27632 partly reversed the dasatinib-induced changes in vitro and ex vivo, presumably by acting downstream of Src. Co-administration of the Rho-kinase inhibitor Y27632 completely blunted the increased pulmonary pressure in response to dasatinib. In conclusion, a dasatinib-induced permeability increase in human pulmonary arterial macro- and microvascular ECs might explain many of the adverse effects of dasatinib in patients. Rho-kinase inhibition might be suitable to ameliorate these effects.

Dasatinib-loaded albumin nanoparticles possess diminished endothelial cell barrier disruption and retain potent anti-leukemia cell activity

Dasatinib (DAS), a second-generation tyrosine kinase inhibitor, is highly effective in treating chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia. However, its clinical use is limited due to serious adverse effects. DAS can disrupt endothelial barrier integrity and increase endothelial permeability which may cause peripheral edema and pleural effusion. Albumin nanoparticles (NPs) as a drug carrier may serve as a useful tool for cell-selective drug delivery to reduce DAS-induced endothelial hyperpermeability and maintain endothelial barrier integrity. In this study, we reported that DAS-loaded NPs exhibited potent anti-leukemia efficacy as DAS alone. Importantly, albumin NPs as a drug carrier markedly reduced DAS-induced endothelial hyperpermeability by restraining the inhibition of Lyn kinase signaling pathway in endothelial cells. Therefore, albumin NPs could be a potential tool to improve anti-leukemia efficacy of DAS through its cell-selective effects.

How to treat chronic myeloid leukemia (CML) in older adults

Chronic myeloid leukemia (CML), a myeloproliferative neoplasm defined by the t(9;22)(q34;q11) chromosomal translocation, primarily affects older adults. Historically, effective treatment options were not available for older CML patients ineligible for curative allogeneic stem cell transplant, and the disease was therefore usually fatal within several years of diagnosis. The development of tyrosine kinase inhibitors (TKIs) that effectively target the constitutively active mutant tyrosine kinase in CML has dramatically improved outcomes for all patients with CML, including older patients. While older patients were underrepresented in prospective trials, TKI therapy can be successfully administered to older adults with CML with excellent efficacy and proven tolerability. TKI selection and monitoring for adverse events should be tailored based on co-morbidities. As with younger patients, life expectancy of older adults with CML now approaches that of age-matched controls. Here we review guidelines for management of older adults with CML.

Dasatinib increases endothelial permeability leading to pleural effusion

Pleural effusion is a frequent side-effect of dasatinib, a second-generation tyrosine kinase inhibitor used in the treatment of chronic myelogenous leukaemia. However, the underlying mechanisms remain unknown. We hypothesised that dasatinib alters endothelial integrity, resulting in increased pulmonary vascular endothelial permeability and pleural effusion.To test this, we established the first animal model of dasatinib-related pleural effusion, by treating rats with a daily regimen of high doses of dasatinib (10 mg·kg^-1·day^-1 for 8 weeks).Pleural ultrasonography revealed that rats chronically treated with dasatinib developed pleural effusion after 5 weeks. Consistent with these in vivo observations, dasatinib led to a rapid and reversible increase in paracellular permeability of human pulmonary endothelial cell monolayers as reflected by increased macromolecule passage, loss of vascular endothelial cadherin and zonula occludens-1 from cell-cell junctions, and the development of actin stress fibres. These results were replicated using human umbilical vein endothelial cells and confirmed by decreased endothelial resistance. Interestingly, we demonstrated that this increased endothelial permeability is a reactive oxygen species (ROS)-dependent mechanism in vitro and in vivo using a cotreatment with an antioxidant agent, N-acetylcysteine.This study shows that dasatinib alters pulmonary endothelial permeability in a ROS-dependent manner in vitro and in vivo leading to pleural effusion.

The incidence and natural history of dasatinib complications in the treatment of chronic myeloid leukemia

Dasatinib has shown superiority over imatinib in achieving molecular responses (MRs) in chronic phase chronic myeloid leukemia but with a different toxicity profile, which may impact its overall benefit. Reported toxicities include pleural effusions and pulmonary hypertension, and although the incidence of these events is well described, response to therapy and impact of dose modifications on toxicity has not been comprehensively characterized in a real-world setting. We retrospectively reviewed the incidence of dasatinib adverse events in 212 chronic phase chronic myeloid leukemia patients at 17 Australian institutions. Adverse events were reported in 116 patients (55%), most commonly pleural effusions (53 patients, 25%), which was the predominant cause of permanent drug cessation. Age and dose were risk factors for pleural effusion (P < .01 and .047, respectively). Recurrence rates were higher in those who remained on 100 mg compared with those who dose reduced (P = .041); however, recurrence still occurred at 50 mg. Patients who developed pleural effusions were more likely to have achieved MR4.5 after 6 months of dasatinib than those without effusions (P = .008). Pulmonary hypertension occurred in 5% of patients, frequently in association with pleural effusion, and was reversible upon dasatinib cessation in 6 of 7 patients. Dose reductions and temporary cessations had minimal impact on MR rates. Our observations suggest that by using the lowest effective dose in older patients to minimize the effusion risk, dose modification for cytopenias, and care with concomitant antiplatelet therapy, the necessity for permanent dasatinib cessation due to toxicity is likely to be minimal in immunologically competent patients.

Cardiovascular Complications of Targeted Therapies for Chronic Myeloid Leukemia

OPINION STATEMENT

The development of tyrosine kinase inhibitors (TKIs) dramatically changed the treatment landscape for many different cancers including chronic myeloid leukemia (CML). With the introduction of imatinib, the first TKI developed and approved to effectively treat CML, patient survival has increased dramatically and, in some cases, this fatal cancer can be managed as a chronic disease. Since the approval of imatinib in 2002, four additional TKIs have been developed to treat this disease including the second-generation TKIs nilotinib, dasatinib, and bosutinib and the third-generation TKI ponatinib. Despite their significant impact on the progression of CML, there is increasing recognition of cardiovascular toxicities which can limit their long-term use and impact patient morbidity and mortality. The majority of the cardiotoxicities are associated with the second- and third-generation TKIs, the most concerning of which are vascular events including myocardial infarction, stroke and peripheral arterial disease. In addition, QT prolongation, pleural effusions, and both systemic and pulmonary hypertension are also observed. It is essential for both cardiologists and oncologists to possess knowledge of these issues in order to develop appropriate monitoring and risk mitigation strategies to prevent these toxicities and avoid premature cessation of the drug.

Association of pleural effusion with an early molecular response in patients with newly diagnosed chronic-phase chronic myeloid leukemia receiving dasatinib: Results of a D-First study

Despite the efficacy and safety of dasatinib treatment for chronic-phase chronic myeloid leukemia (CML-CP), adverse effects such as pleural effusion (PE) are still a serious concern. We determined the clinical significance of PE incidence using patient data derived from the D-First clinical study. In the present study, chest radiography and quantification of specific lymphocyte subsets were performed routinely after initiation of dasatinib treatment. Among 52 patients with newly diagnosed CML-CP, 17 (33%) developed PE within 18 months after initial dasatinib administration, but all cases were moderate (Grade 1, 10 patients; Grade 2, 7 patients). CD56+ lymphocyte counts at 1 month correlated significantly with the incidence of PE, whereas lymphocytosis did not. The major molecular response (MMR) rate at 3 months (although not at later times) was significantly higher in PE-positive patients than PE-negative patients (59% versus 24%, respectively; P=0.013). Deep molecular response rates did not differ significantly between the PE groups at any time point during the observation period. Our results suggest that an immune-mediated mechanism involving natural killer cells underlies the development of PE in patients receiving dasatinib for 18 months. This mechanism likely promotes transient tumor regression in patients newly diagnosed with CML-CP.

European LeukemiaNet recommendations for the management and avoidance of adverse events of treatment in chronic myeloid leukaemia

Most reports on chronic myeloid leukaemia (CML) treatment with tyrosine kinase inhibitors (TKIs) focus on efficacy, particularly on molecular response and outcome. In contrast, adverse events (AEs) are often reported as infrequent, minor, tolerable and manageable, but they are increasingly important as therapy is potentially lifelong and multiple TKIs are available. For this reason, the European LeukemiaNet panel for CML management recommendations presents an exhaustive and critical summary of AEs emerging during CML treatment, to assist their understanding, management and prevention. There are five major conclusions. First, the main purpose of CML treatment is the antileukemic effect. Suboptimal management of AEs must not compromise this first objective. Second, most patients will have AEs, usually early, mostly mild to moderate, and which will resolve spontaneously or are easily controlled by simple means. Third, reduction or interruption of treatment must only be done if optimal management of the AE cannot be accomplished in other ways, and frequent monitoring is needed to detect resolution of the AE as early as possible. Fourth, attention must be given to comorbidities and drug interactions, and to new events unrelated to TKIs that are inevitable during such a prolonged treatment. Fifth, some TKI-related AEs have emerged which were not predicted or detected in earlier studies, maybe because of suboptimal attention to or absence from the preclinical data. Overall, imatinib has demonstrated a good long-term safety profile, though recent findings suggest underestimation of symptom severity by physicians. Second and third generation TKIs have shown higher response rates, but have been associated with unexpected problems, some of which could be irreversible. We hope these recommendations will help to minimise adverse events, and we believe that an optimal management of them will be rewarded by better TKI compliance and thus better CML outcomes, together with better quality of life.

Chronic myeloid leukemia: Second-line drugs of choice

The efficacy of second-line treatment for chronic myeloid leukemia (CML) plays an important role in allowing CML patients to enjoy a normal life expectancy. Four tyrosine kinase inhibitors (TKIs) are presently available: bosutinib, dasatinib, nilotinib, ponatinib. Each one has different safety and activity profiles, which are reviewed here. No controlled studies are available to guide treatment decision, which must be based on the characterization of leukemic cells, especially in cases of resistance to TKI, coupled with the safety profile of each TKI. Patient comorbidities also play an important role in the treatment decision, which can achieve a new durable response in over 50% of treated patients.

Acute pulmonary complications in patients with hematologic malignancies

Various acute pulmonary complications may occur in patients with hematologic malignancies because they are in an immunocompromised state due to systemic disease or to chemotherapy or hematopoietic stem cell transplantation. Pulmonary complications may arise from other treatment regimens, as well, or from direct pulmonary involvement in the malignant disease process. The differential diagnosis of pulmonary opacities in patients with hematologic malignancies is broad and includes both infectious and noninfectious causes. Pulmonary hemorrhage, edema, leukostasis, and pneumonia are well-known and common acute pulmonary complications. Less common complications are now encountered with increasing frequency because of the increasing complexity of therapeutic regimens for hematologic malignancies, which may include various drugs that are in clinical trials or were recently released to market. These once uncommon acute pulmonary complications include retinoic acid syndrome, tyrosine kinase inhibitor-induced pulmonary complications, engraftment syndrome, and hemophagocytic lymphohistiocytosis. It is often difficult to differentiate between these entities. However, the clinical setting and radiologic imaging findings may provide clues for interpreting imaging findings of abnormal pulmonary opacity in patients with a hematologic malignancy. Pulmonary hemorrhage is characterized by a sudden onset of symptoms and rapid progression of pulmonary imaging abnormalities and usually occurs in patients with impaired coagulation or a predisposition to bleed. Pulmonary edema should be considered when typical findings of hydrostatic pulmonary edema are seen. Pulmonary leukostasis develops in patients with hyperleukocytosis and leads to symptoms such as a cough, fever, and dyspnea. Various types of pneumonia may develop, depending on the degree and duration of immunosuppression in the patient. Retinoic acid syndrome, tyrosine kinase inhibitor-induced pulmonary complications, and engraftment syndrome occur after specific treatments, so a detailed medical history including recent or current treatments may be helpful for diagnosis. Accurate differentiation of these entities allows their appropriate management, with resultant decreases in morbidity and mortality.

First-line treatment of newly diagnosed elderly patients with chronic myeloid leukemia: current and emerging strategies

Chronic myeloid leukemia (CML) is a disease of the hematopoietic stem cell characterized by a median age at diagnosis of 60-65 years according to most epidemiologic registries. Prior to the tyrosine kinase inhibitor (TKI) era, older age was considered an adverse prognostic factor and was included in two of the most used scoring systems for CML, the Sokal score and the Euro score. Moreover, older age was generally considered a limitation for the use of allogeneic stem-cell transplantation, given the higher toxicity observed. After the introduction of TKIs, age lost much of its prognostic impact in patients in chronic phase (CP), and the EUTOS score, developed in patients treated with imatinib, did not identify age as a risk variable. However, most CML patients require life-long treatment; therefore, as patients age while taking a TKI, the complexity of the management of elderly patients may increase over time. To date, imatinib, the first TKI introduced, and two second-generation TKIs, nilotinib and dasatinib, have been approved in most Western countries for the first-line treatment of CML. These drugs differ in terms of efficacy, safety, and costs; therefore, knowledge of their characteristics is extremely relevant for optimal management of elderly CML patients. We reviewed the impact of age on the first-line treatment of CP CML patients in the TKI era, considering the epidemiology of the disease, the role of comorbidities, and analyzing data from population-based studies and clinical trials.

Management of adverse events associated with tyrosine kinase inhibitors in chronic myeloid leukemia

Tyrosine kinase inhibitors (TKIs) targeting the breakpoint cluster region-Abelson 1 (BCR-ABL1) oncoprotein represent an outstanding progress in chronic myeloid leukemia (CML), and long-term survival has become a reality. However, the majority of patients need to be treated during their entire life span; thus, outcome does not solely depend on treatment efficacy but also on how well therapy is tolerated. TKIs have an overall favorable safety profile in clinical practice. Although many patients may encounter adverse events, these usually occur early after treatment initiation, are mild to moderate in intensity and resolve spontaneously, or are easily controlled with adequate supportive care. Whenever treatment interruption is necessary, re-exposition to the same TKI or switch to an alternative TKI is successful in the majority of the cases. However, long-term safety issues have not been fully elucidated at present, especially for new-generation TKIs. Recent evidence has emerged that these new agents may sometimes impinge on vital organs such as the heart and lung in an irreversible fashion especially when comorbidities are present; thus, decision regarding of which TKI should be used must take into account disease-related, TKI-related, and patient-related variables. The purpose of this article is to provide an up-to-date review of common adverse events associated with TKIs and how these events may be optimally managed.

TIDEL-II: first-line use of imatinib in CML with early switch to nilotinib for failure to achieve time-dependent molecular targets

The Therapeutic Intensification in De Novo Leukaemia (TIDEL)-II study enrolled 210 patients with chronic phase chronic myeloid leukemia (CML) in two equal, sequential cohorts. All started treatment with imatinib 600 mg/day. Imatinib plasma trough level was performed at day 22 and if <1000 ng/mL, imatinib 800 mg/day was given. Patients were then assessed against molecular targets: BCR-ABL1 ≤10%, ≤1%, and ≤0.1% at 3, 6, and 12 months, respectively. Cohort 1 patients failing any target escalated to imatinib 800 mg/day, and subsequently switched to nilotinib 400 mg twice daily for failing the same target 3 months later. Cohort 2 patients failing any target switched to nilotinib directly, as did patients with intolerance or loss of response in either cohort. At 2 years, 55% of patients remained on imatinib, and 30% on nilotinib. Only 12% were >10% BCR-ABL1 at 3 months. Confirmed major molecular response was achieved in 64% at 12 months and 73% at 24 months. MR4.5 (BCR-ABL1 ≤0.0032%) at 24 months was 34%. Overall survival was 96% and transformation-free survival was 95% at 3 years. This trial supports the feasibility and efficacy of an imatinib-based approach with selective, early switching to nilotinib. This trial was registered at www.anzctr.org.au as #12607000325404.

Comorbidities and polypharmacy impact on complete cytogenetic response in chronic myeloid leukaemia elderly patients

BACKGROUND

In older patients comorbidity and polypharmacy can significantly influence the success of the treatment, as well as the cognitive and psycho-social aspects. A significant proportion of chronic myeloid leukaemia (CML) patients are "elderly": in the past the aim of therapy in this subset of patients was only to contain the leukaemic mass, but nowadays, with the advent of the protein-tyrosine kinase inhibitors, also elderly patients can access these treatments. We want to assess if even old CML patients, with a correct geriatric evaluation, can be successfully treated with protein-tyrosine kinase inhibitors.

METHODS

A complete geriatric evaluation in 16 old CML patients aged >65years treated with TKI was performed in order to assess the comorbidity, the polypharmacy and the cognitive, physical and psychological states. The Charlson comorbity index (CCI) and the polypharmacy were correlated to the obtained cytogenetic response. Seven scales of geriatric evaluation were used to assess the autonomy of patients before they were included into the study.

RESULTS

In our cohort of elderly patients treated with imatinib, comorbidities and polypharmaco-therapy demonstrated an influence on TKI therapeutic success. In fact, the majority of complete cytogenetic response was obtained by patients who presented a low score of CCI and did not take any other drugs other than TKI.

CONCLUSION

Also old chronic myeloid leukaemia patients can benefit from TKI treatment if a good cooperation between the haematologist and the geriatrician is established.

A critical role for Lyn kinase in strengthening endothelial integrity and barrier function

The Src family kinases (SFKs) c-Src and Yes mediate vascular leakage in response to various stimuli including lipopolysaccharide (LPS) and vascular endothelial growth factor (VEGF). Here, we define an opposing function of another SFK, Lyn, which in contrast to other SFKs, strengthens endothelial junctions and thereby restrains the increase in vascular permeability. Mice lacking Lyn displayed increased mortality in LPS-induced endotoxemia and increased vascular permeability in response to LPS or VEGF challenge compared with wild-type littermates. Lyn knockout mice repopulated with wild-type bone marrow-derived cells have higher vascular permeability than wild-type mice, suggesting a role of endothelial Lyn in the maintenance of the vascular barrier. Small interfering RNA-mediated down-regulation of Lyn disrupted endothelial barrier integrity, whereas expression of a constitutively active mutant of Lyn enhanced the barrier. However, down-regulation of Lyn did not affect LPS-induced endothelial permeability. We demonstrate that Lyn association with focal adhesion kinase (FAK) and phosphorylation of FAK at tyrosine residues 576/577 and 925 were required for Lyn-dependent stabilization of endothelial adherens junctions. Thus, in contrast to c-Src and Yes, which increase vascular permeability in response to stimuli, Lyn stabilizes endothelial junctions through phosphorylation of FAK. Therefore, therapeutics activating Lyn kinase may strengthen the endothelial barrier junction and hence have anti-inflammatory potential.