Chronic myeloid leukemia in the elderly: long-term results from randomized trials with interferon alpha

Prognosis in Chronic Myeloid Leukemia: Baseline Factors, Dynamic Risk Assessment and Novel Insights

The introduction of tyrosine kinase inhibitors (TKIs) has changed the treatment paradigm of chronic myeloid leukemia (CML), leading to a dramatic improvement of the outcome of CML patients, who now have a nearly normal life expectancy and, in some selected cases, the possibility of aiming for the more ambitious goal of treatment-free remission (TFR). However, the minority of patients who fail treatment and progress from chronic phase (CP) to accelerated phase (AP) and blast phase (BP) still have a relatively poor prognosis. The identification of predictive elements enabling a prompt recognition of patients at higher risk of progression still remains among the priorities in the field of CML management. Currently, the baseline risk is assessed using simple clinical and hematologic parameters, other than evaluating the presence of additional chromosomal abnormalities (ACAs), especially those at "high-risk". Beyond the onset, a re-evaluation of the risk status is mandatory, monitoring the response to TKI treatment. Moreover, novel critical insights are emerging into the role of genomic factors, present at diagnosis or evolving on therapy. This review presents the current knowledge regarding prognostic factors in CML and their potential role for an improved risk classification and a subsequent enhancement of therapeutic decisions and disease management.

CML in Elderly: Does Age Matter?

The median age of diagnosis for chronic myeloid leukemia (CML) in India is 35 years on the contrary to western literature which is 47 years. The outcome of the elderly patient in CML TKI era is not reported from the Indian population. However, Western literature suggests that use of TKI alleviate the adverse impact of age in outcomes of CML. This study was carried out to analyze the clinical profile and outcome of elderly, in comparison with younger patients with CML. We retrospectively analyzed CML patients treated at our department from January 2008 to December 2017. The data cutoff date was December 2018. The cohorts of 712 patients were divided into two groups. Patients belonging to the age group of ≥ 60 years were classified as the study group and those who were 18-60 years were used as controls. Patient's clinical history, examination and milestones in terms of achieving hematological, molecular responses and toxicity profile were also recorded. The total of 712 patients, 52 patients in the study group and 660 patients in the control group were treated during the study period. The study group was having more co-morbidities than the control group (15.3% vs. 4.5%). Patients having high-risk EUTOS score were similar in both groups (38.4% vs. 37.6%). The patients presented in blast phase were higher in the study group as compared to control group (9.6% vs. 6.36%) but the differences were not statistically significant. Rates of achieving a hematological response at 3 months (85.1% vs. 86.89%) and the major molecular response at 18 months (54.3% vs. 60.16%) were almost similar in both groups. However, hematological toxicity, muscle cramps and gastritis were reported more in elderly patients. The outcome of CML patients in TKI era do not differ in elderly patients. However, toxicity profile was not significantly inferior in elderly patients.

Impact of age on efficacy and toxicity of nilotinib in patients with chronic myeloid leukemia in chronic phase: ENEST1st subanalysis

Purpose

Achievement of deep molecular response with a tyrosine kinase inhibitor in patients with chronic myeloid leukemia (CML) is required to attempt discontinuation of therapy in these patients. The current subanalysis from the Evaluating Nilotinib Efficacy and Safety in Clinical Trials as First-Line Treatment (ENEST1st) study evaluated whether age has an impact on the achievement of deeper molecular responses or safety with frontline nilotinib in patients with CML.

Methods

ENEST1st is an open-label, multicenter, single-arm, prospective study of nilotinib 300 mg twice daily in patients with newly diagnosed CML in chronic phase. The patients were stratified into the following 4 groups based on age: young (18–39 years), middle age (40–59 years), elderly (60–74 years), and old (≥75 years). The primary end point was the rate of molecular response 4 ([MR⁴] BCR–ABL1 ≤0.01% on the international scale) at 18 months from the initiation of nilotinib.

Results

Of the 1091 patients enrolled, 1089 were considered in the analysis, of whom, 23% (n = 243), 45% (n = 494), 27% (n = 300), and 5% (n = 52) were categorized as young, middle age, elderly, and old, respectively. At 18 months, the rates of MR⁴ were 33.9% (95% confidence interval [CI], 27.8–40.0%) in the young, 39.6% (95% CI, 35.3–44.0%) in the middle-aged, 40.5% (95% CI, 34.8–46.1%) in the elderly, and 35.4% (95% CI, 21.9–48.9%) in the old patients. Although the incidence of adverse events was slightly different, no new specific safety signals were observed across the 4 age groups.

Conclusions

This subanalysis of the ENEST1st study showed that age did not have a relevant impact on the deep molecular response rates associated with nilotinib therapy in newly diagnosed patients with CML and eventually on the eligibility of the patients to attempt treatment discontinuation.

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.

Older patients with chronic myeloid leukemia (≥65 years) profit more from higher imatinib doses than younger patients: a subanalysis of the randomized CML-Study IV

The impact of imatinib dose on response rates and survival in older patients with chronic myeloid leukemia in chronic phase has not been studied well. We analyzed data from the German CML-Study IV, a randomized five-arm treatment optimization study in newly diagnosed BCR-ABL-positive chronic myeloid leukemia in chronic phase. Patients randomized to imatinib 400 mg/day (IM400) or imatinib 800 mg/day (IM800) and stratified according to age (≥65 years vs. <65 years) were compared regarding dose, response, adverse events, rates of progression, and survival. The full 800 mg dose was given after a 6-week run-in period with imatinib 400 mg/day. The dose could then be reduced according to tolerability. A total of 828 patients were randomized to IM400 or IM800. Seven hundred eighty-four patients were evaluable (IM400, 382; IM800, 402). One hundred ten patients (29 %) on IM400 and 83 (21 %) on IM800 were ≥65 years. The median dose per day was lower for patients ≥65 years on IM800, with the highest median dose in the first year (466 mg/day for patients ≥65 years vs. 630 mg/day for patients <65 years). Older patients on IM800 achieved major molecular remission and deep molecular remission as fast as younger patients, in contrast to standard dose imatinib with which older patients achieved remissions much later than younger patients. Grades 3 and 4 adverse events were similar in both age groups. Five-year relative survival for older patients was comparable to that of younger patients. We suggest that the optimal dose for older patients is higher than 400 mg/day. ClinicalTrials.gov identifier: NCT00055874

Age influences initial dose and compliance to imatinib in chronic myeloid leukemia elderly patients but concomitant comorbidities appear to influence overall and event-free survival

We applied Charlson comorbidity index (CCI) stratification on a large cohort of chronic myeloid leukemia (CML) very elderly patients (>75 years) treated with imatinib, in order to observe the impact of concomitant diseases on both compliance and outcome. One hundred and eighty-one patients were recruited by 21 Italian centers. There were 95 males and 86 females, median age 78.6 years (range 75-93.6). According to Sokal score, 106 patients were classified as intermediate risk and 55 as high risk (not available in 20 patients). According to CCI stratification, 71 patients had score 0 and 110 a score ≥ 1. Imatinib standard dose was reduced at start of therapy (200-300 mg/day) in 68 patients independently from the evaluation of baseline comorbidities, but based only on physician judgement: 43.6% of these patients had score 0 compared to 34% of patients who had score ≥ 1. Significant differences were found in terms of subsequent dose reduction (39% of patients with score 0 compared to 53% of patients with score ≥ 1) and in terms of drug discontinuation due to toxicity (35% of patients with score 0 vs 65% of patients with score ≥ 1). We did not find significant differences as regards occurrence of hematologic side effects, probably as a consequence of the initial dose reduction: 39% of patients with score 0 experienced grade 3/4 hematologic toxicity (most commonly anemia) compared to 42% of patients with score ≥ 1. Independently from the initial dose, comorbidities again did not have an impact on development of grade 3/4 non-hematologic side effects (most commonly skin rash, muscle cramps and fluid retention): 62% of patients with score 0 compared to 52.5% of patients with score ≥ 1. Notwithstanding the reduced dose and the weight of comorbidities we did not find significant differences but only a trend in terms of efficacy: 66% of patients with score 0 achieved a CCyR compared to 54% of patients with score ≥ 1. Comorbidities appeared to have an impact on median OS (40.8 months for patients with score 0 vs 20.16 months for patients with score ≥ 1) on EFS and on non-CML death rate. Our results suggest that treatment of very elderly CML patients might be influenced by personal physician perception: evaluation at baseline of comorbidities according to CCI should improve initial decision-making in this subset of patients.

Comparative study for the efficacy, safety and quality of life in patients of chronic myeloid leukemia treated with Imatinib or Hydroxyurea

Objective:

Chronic myeloid leukemia (CML) is a clonal hematopoietic disorder caused by acquired genetic defect in pluripotent stem cells characterized by acquisition of the philadelphia chromosome. The aim of this study was to compare the efficacy, safety and quality of life (QoL) in CML patients treated with imatinib or hydroxyurea.

Methods:

A prospective observational study was conducted on 40 patients with pathologically confirmed CML in an in-patient department of Mahavir Cancer Sansthan and Research Centre (tertiary care cancer hospital) in India. Patients were divided into two groups (group A: Imatinib consuming patients and group B: Hydroxyurea consuming patients). Complete blood count was done every month to assess the efficacy and safety/toxicity profile of these drugs. The results were analyzed 12 months after completion of treatment. QoL was assessed by The European Organization for Research and Treatment of Cancer QoL Questionnaire core 30. Hematological response was analyzed using kaplan-meier survival analysis. Chi-square test was applied to assess the association of two regimens with complete hematological response, hematological and non-hematological toxicity. White blood cell (WBC) was noted each month in every patient of each group and analyzed by generalized linear mode (repeated measures) analysis of variance (ANOVA). Independent t-test was used to compare changes in QoL between treatment groups.

Findings:

At the end of treatment, significant improvement (P = 0.001) in hematological response was observed in the group A (95%) compared to group B (30%). WBC count analyzed at each month of treatment by ANOVA achieved better results for patients treated with imatinib (P = 0.0001). The hematological toxicity was higher in imatinib group while non-hematological toxicity was higher in the hydroxyurea group; however only little toxicities such as nausea and constipation were statistically significant. QoL assessment of patients related to functional scale showed significantly better results in group A (P = 0.046).

Conclusion:

The study showed that imatinib has better profile compared to hydroxyurea, with siginificant statistical differences in terms of efficacy, non-hematological toxicity and QoL in CML patients. Even with such better efficacy and safety profile, pharmacoeconomic evaluation needs to be done to justify and support the use of imatinib for CML patients in India.

Long-term safety and efficacy of imatinib mesylate (Gleevec®) in elderly patients with chronic phase chronic myelogenous leukemia: results of the AFR04 study

Data from registries suggest that the median age of chronic myelogenous leukemia (CML) patients is 10-15 years older than that of clinical trials. We conducted a prospective phase II study to evaluate imatinib mesylate (IM, 400 mg daily) in newly diagnosed chronic phase CML (CP-CML) patients. Patients aged 70 years and over diagnosed with CP-CML within 12 months were eligible. Thirty patients were enrolled from April 2002 to October 2004. Median age was 74.8 years (range, 70-90). Male/female ratio was 1.72. At inclusion, comorbidities were reported in all but one patient, Cumulative Illness Rating Scale for Geriatrics comorbidity mean index was 1.47, and 66% of patients had cardiovascular disease. The median daily IM dose was 392 mg (range, 256-445). IM was interrupted in patients with severe comorbidities. Treatment discontinuation was observed in 36.6% of patients. Cumulative incidence of complete cytogenetic response was 71.4 and 78.5% at 12 and 24 months, respectively. A high level of sustained responses was observed in patients with mild or moderate comorbidities. Seven-year estimated overall survival was 80.8% (95% CI: 59.0-91.7). Two-thirds of the patients were still on long-term therapy at cut-off, and no patients had died from progression. This trial was registered at http://www.clinicaltrials.gov as # NCT00219765.

Frontline imatinib treatment of chronic myeloid leukemia: no impact of age on outcome, a survey by the GIMEMA CML Working Party

The median age of chronic myeloid leukemia (CML) patients is ∼ 60 years, and age is still considered an important prognostic factor, included in Sokal and EURO risk scores. However, few data are available about the long-term outcome of older patients treated with imatinib (IM) frontline. We analyzed the relationship between age and outcome in 559 early chronic-phase CML patients enrolled in 3 prospective clinical trials of Gruppo Italiano Malattie Ematologiche dell'Adulto CML Working Party, treated frontline with IM, with a median follow-up of 60 months. There were 115 older patients (≥ 65 years; 21%). The complete cytogenetic and major molecular response rates were similar in the 2 age groups. In older patients, event-free survival (55% vs 67%), failure-free survival (78% vs 92%), progression-free survival (62% vs 78%), and overall survival (75% vs 89%) were significantly inferior (all P < .01) because of a higher proportion of deaths that occurred in complete hematologic response, therefore unrelated to CML progression (15% vs 3%, P < .0001). The outcome was similar once those deaths were censored. These data show that response to IM was not affected by age and that the mortality rate linked to CML is similar in both age groups. This trial was registered at www.clinicaltrials.gov as #NCT00514488 and #NCT00510926.

Chronic myeloid leukaemia

Chronic myeloid leukaemia (CML) was the first neoplastic disease for which knowledge of the genotype led to a rationally designed therapy. As a result of its well known pathophysiology, straightforward diagnosis, well established prognostic factors, and treatment for the cause of disease, CML has been studied to an extent that far exceeds that expected from its frequency, and serves as a model disease for other cancers. Imatinib, an inhibitor of BCR-ABL tyrosine kinase, has revolutionised treatment of this disease, and is now recommended as standard treatment for chronic-phase CML. Interferon alfa is an acceptable alternative treatment in the early chronic phase for patients who do not tolerate imatinib. If imatinib treatment fails, allogeneic stem-cell transplantation, a dose increase of imatinib, or new drugs are recommended. Up to 87% of patients achieve complete cytogenetic remission, therefore we provide guidance for monitoring disease status. Many trials of new drugs and combination therapies that include imatinib are underway.

Poorer outcome of elderly patients treated with extended-field radiotherapy compared with involved-field radiotherapy after chemotherapy for Hodgkin's lymphoma: an analysis from the German Hodgkin Study Group

BACKGROUND

The optimal treatment of elderly patients with Hodgkin's lymphoma (HL) is still a matter of debate. Since many of these patients receive combined modality treatment, we evaluated the impact of different radiation field sizes, that is extended-field (EF) or involved-field (IF) technique when given after four cycles of chemotherapy.

PATIENTS AND METHODS

In the multicenter HD8 study of the German Hodgkin Study Group, 1204 patients with early-stage unfavorable HL were randomized to receive four cycles of chemotherapy followed by either radiotherapy (RT) of 30 Gy EF + 10 Gy to bulky disease (arm A) or 30 Gy IF + 10 Gy to bulky disease (arm B). A total of 1064 patients were assessable for the analysis. Of these, 89 patients (8.4%) were 60 years or older.

RESULTS

Elderly patients had a poorer risk profile. Acute toxicity from RT was more pronounced in elderly patients receiving EF-RT compared with IF-RT [World Health Organization (WHO) grade 3/4: 26.5% versus 8.6%)]. Freedom from treatment failure (FFTF, 64% versus 87%) and overall survival (OS, 70% versus 94%) after 5 years was lower in elderly patients compared with younger patients. Importantly, elderly patients had poorer outcome when treated with EF-RT compared with IF-RT in terms of FFTF (58% versus 70%; P = 0.034) and OS (59% versus 81%; P = 0.008).

CONCLUSION

Elderly patients with early-stage unfavorable HL generally have a poorer risk profile and outcome when compared with younger patients. Treatment with EF-RT instead of IF-RT after chemotherapy has a negative impact on survival of elderly patients and should be avoided.

Chronic myeloid leukemia: a model for oncology

Leukemias have traditionally served as model systems for research on neoplasia because of the easy availability of cell material from blood and marrow for diagnosis, monitoring and studies on pathophysiology. Beyond these more technical aspects, chronic myeloid leukemia (CML) became the first neoplasia in which the elucidation of the genotype led to a rationally designed therapy of the phenotype. Targeting of the pathogenetically relevant BCR-ABL tyrosine kinase with the selective kinase inhibitor imatinib has induced remissions with almost complete disappearance of any signs and symptoms of CML. This therapeutic success has triggered an intensive search for target structures in other cancers and has led to the development of numerous inhibitors of potential targets, which are being studied in preclinical and clinical trials worldwide. This review deals with some of the recent developments that have evolved since our last review in this journal in 2000 (Hehlmann R, Hochhaus A, Berger U, Reiter A (2000) Current trends in the management of chronic myelogenous leukemia.

Gender aspects in chronic myeloid leukemia: long-term results from randomized studies

Gender-related aspects in chronic myeloid leukemia (CML) have not been studied well. We therefore analyzed 856 patients with Ph/BCR-ABL-positive CML from the German randomized CML-studies I (interferon alpha (IFN) vs hydroxyurea (HU) vs busulfan) and II (IFN+HU vs HU alone). The median observation time was 8.6 years. A total of 503 patients (59%) were male. Female patients were older (51 vs 46 years; P<0.0001), presented with lower hemoglobin (11.7 vs 12.5 g/dl; P<0.0001), higher platelet counts (459 vs 355 x 10(9)/l; P<0.0001), smaller spleen size (3 vs 4 cm below costal margin; P=0.0097), a lower rate of additional cytogenetic aberrations (9 vs 15%; P=0.018) and a less favorable risk profile (P=0.036). The transplantation rate was 14% for female (n=48) and 22% for male patients (n=113). Median survival was longer in female patients (58 vs 49 months; P=0.035) mainly attributable to better survival in the low- and intermediate-risk groups and, independent from risk groups, in the HU group. These results were confirmed by matched-pair analyses based on German population data (n=496, 59 vs 45 months; P=0.0006). This is the first analysis of gender aspects in CML using randomized trials. It demonstrates the relevance of analyses of gender differences in CML and in malignant disease at large.

Elderly patients with Ph+ chronic myelogenous leukemia (CML): results of imatinib mesylate treatment

Thirty-five patients with Ph+ CML aged more than 60 years were treated with imatinib. Twenty-four patients (group A) were in late chronic phase (CP) and eleven patients (group B) were in accelerated/blastic phase (AP/BP). In group A, complete haematological response (CHR) was achieved by all patients; seventeen patients (70.8%) attained a complete cytogenetic response (CCR), one (4.1%) attained a partial CR, one (4.1%) a minor CR (Ph+ 70%) and five (21%) were resistant (Ph+ 100%), toxicity was mild: seven patients had a transient cytopenia, three a skin reaction, one a moderate oedema and one muscular pain. After a median follow-up of 15 months, 1 patient died in progression and 23 patients are alive (2 in BP and 21 in persisting response). In group B, one patient died after 3 months in aplastic phase from sepsis, three patients were resistant and seven patients (63.7%) achieved CHR; of these, four obtained CCR. After a median follow-up of 17 months, 4 patients have died from progressive disease, 6 are alive; 1 in AP and 5 in CHR (4 of them being in CCR). Present data indicate that imatinib is safe also in elderly with clinical results as good as in younger patients.

VEGF and myeloid leukemias

Vascular endothelial growth factor and vascular endothelial growth factor receptors participate in the growth and survival of myeloid leukemic progenitors. With the development of multiple anti-angiogenic agents, there is potential that some of these novel agents will have anti-leukemic activity. Since these agents work by mechanisms distinct from current cytotoxic chemotherapies, they may be useful both in chemoresistant leukemia patients and in combinations to improve remission rates and remission durations.