Early mortality and overall survival in acute promyelocytic leukemia: do real-world data match results of the clinical trials?

Clinical networking results in continuous improvement of the outcome of patients with acute promyelocytic leukemia

ABSTRACT

The introduction of all-trans retinoic acid combined with anthracyclines has significantly improved the outcomes for patients diagnosed with acute promyelocytic leukemia (APL), and this strategy remains the standard of care in countries in which arsenic trioxide is not affordable. However, data from national registries and real-world databases indicate that low- and middle-income countries (LMIC) still face disappointing results, mainly because of high induction mortality and suboptimal management of complications. The American Society of Hematology established the International Consortium on Acute Leukemias (ICAL) to address this challenge through international clinical networking. Here, we present the findings from the International Consortium on Acute Promyelocytic Leukemia study involving 806 patients with APL recruited from 2005 to 2020 in Brazil, Chile, Paraguay, Peru, and Uruguay. The induction mortality rate has notably decreased to 14.6% compared with the pre-ICAL rate of 32%. Multivariable logistic regression analysis revealed as factors associated with induction death: age of ≥40 years, Eastern Cooperative Oncology Group performance status score of 3, high-risk status based on the Programa Español de Tratamiento en Hematologia/Gruppo Italiano Malattie EMatologiche dell'Adulto classification, albumin level of ≤3.5 g/dL, bcr3 PML/RARA isoform, the interval between presenting symptoms to diagnosis exceeding 48 hours, and the occurrence of central nervous system and pulmonary bleeding. With a median follow-up of 53 months, the estimated 4-year overall survival rate is 81%, the 4-year disease-free survival rate is 80%, and the 4-year cumulative incidence of relapse rate is 15%. These results parallel those observed in studies conducted in high-income countries, highlighting the long-term effectiveness of developing clinical networks to improve clinical care and infrastructure in LMIC.

The influence of hospital volume and physician volume on early mortality in acute promyelocytic leukemia patients

Acute promyelocytic leukemia (APL) is a highly curable hematologic malignancy in the era of all-trans retinoic acid (ATRA) combination treatment. However, only a modest change in early mortality rate has been observed despite the wide availability of ATRA. In addition to the clinical characteristics of APL patients, studies on the hospital volume-outcome relationship and the physician volume-outcome relationship remained limited. We aim to evaluate the association between hospital and physician volume and the early mortality rate among APL patients. The patients were collected from Taiwan's National Health Insurance Research Database (NHIRD). Early mortality is defined as death within 30 days of diagnosis. Patients were categorized into four groups according to individual cumulative hospital and physician volume. The risk of all-cause mortality in APL patients with different cumulative volume groups was compared using a Cox proportional hazard model. The probability of overall survival was estimated using the Kaplan-Meier method. All 741 patients were divided into four quartile volume groups. In the multivariate analysis, only physician volume was significantly associated with early mortality rate. The physician volume of the highest quartile was a protective factor for early mortality compared with the physician volume of the lowest quartile (HR 0.10, 95% CI 0.02-0.65). Hospital characteristics were not associated with early mortality. In the sensitivity analyses, the results remained consistent using two other different definitions of early mortality. Higher physician volume was independently associated with lower early mortality, while hospital volume was not. Enhancing the clinical expertise of low-volume physicians may ensure better outcomes.

Causes and risk factors for early death in adult patients with acute promyelocytic leukemia: a real-life experience

INTRODUCTION

Early Death (ED) remains challenging in newly diagnosed acute promyelocytic leukemia (APL), especially in developing countries. The clinical and laboratory profile at diagnosis were evaluated and causes and risk factors were investigated in adult APL patients.

METHOD

A retrospective real-life analysis of 141 medical records was performed of patients diagnosed with APL between 2007 and 2018, whether they were treated with the IC-APL 2006 protocol or not. Risk factors were assessed by univariate and multivariate analysis.

MAIN RESULTS

Overall, 112 patients were included in the study. ED occurred in 22.3% of cases, surpassing clinical trial reports, with non-protocol-eligible patients presenting notably higher rates (60%), potentially due to their clinical status. Hemorrhage (60%) and infection (33.3%) were the leading causes of ED. Univariate analysis associated ED to the ECOG score; white blood cell (WBC) count; body mass index; levels of hemoglobin, albumin, uric acid, and creatinine, aPTT and INR and FLT3 mutations. Multivariate analysis identified ECOG score ≥2 and elevated WBC count as independent risk factors.

CONCLUSION

ED remains a substantial challenge in APL, especially in real-world settings with hemorrhage and infection being the leading causes. ECOG status and WBC count emerged as independent risk factors, while age and platelet count lacked a 30-day prognostic correlation. Evaluating prognostic enhancement tools in controlled trials and real-life settings is pivotal to improving APL outcomes.

Hospital facility characteristics and socioeconomic factors on outcomes and treatment in patients with multiple myeloma: National Cancer Database analysis

Previous studies have shown that socioeconomic factors play an important role in multiple myeloma (MM) health outcomes. We postulated that the type of treatment facilities and their volume of cases also affect overall survival, utilization of various therapies including palliative care services in newly diagnosed MM. Using the National Cancer Database (NCDB), we analyzed 174,551 newly diagnosed MM participants from across the country. We found that at high volume facility centers (over 90^th percentile of new patient volume from 2004 to 2016), the median overall survival (OS) was 62.3 months versus 35.3 months at lower volume facilities (p <0.001). Similarly, high volume academic cancer centers had an improved median OS of 66.4 months (65.3-67.4 CI) versus 39.2 months (37.9-40.4 months CI) in lower volume academic centers (p <0.001). The odds of utilizing chemotherapy, immunotherapy, and autologous transplants were higher in academic cancer centers compared to community cancer centers, after adjusting for demographic and socioeconomic factors (OR 1.10, 1.23, and 2.06 respectively, all with p<0.001). There was significantly decreased odds of receiving palliative care (OR 0.89, 95% CI 0.85-0.93) in high volume facilities compared to low volume. Palliative care services were more frequently utilized at integrated network cancers and comprehensive community cancer centers compared to community cancer centers, with similar odds of receiving palliative care between community and academic facility types. Our results likely reflect increased provider experience and resources in higher volume and academic facilities. This highlights the need to integrate resources and improve access to community programs.

Long-term real-world outcomes of patients with acute promyelocytic leukaemia treated with arsenic trioxide and all-trans retinoic acid without chemotherapy-a retrospective, single-centre study

Arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) form the backbone of the treatment of acute promyelocytic leukaemia (APL), with the addition of chemotherapy for high-risk patients. We describe our experience of treating patients with APL of all risk classes with ATO and ATRA without chemotherapeutic agents. Patients received induction with ATO and ATRA followed by three cycles of consolidation with ATO and ATRA (each 1 month apart) after achieving morphological remission. Patients with intermediate- and high-risk disease received a further 2 years of maintenance with ATRA, 6-mercaptopurine and methotrexate. A total of 206 patients were included in the study. The majority of the patients were intermediate risk (51.9%), followed by high risk (43.2%). Differentiation syndrome was seen in 41 patients (19.9%). Overall, 25 patients (12.1%) died within 7 days of initiating therapy. Seven patients relapsed during follow-up. The mean (SD) estimated 5-year event-free survival (EFS) and overall survival (OS) in the entire cohort was 79% [5.8%] and 80% [5.8%] respectively. After excluding patients who died within 7 days of therapy initiation, the mean (SD) estimated 5-year EFS and OS was 90% [5.8%] and 93% [3.9%] respectively. Our study shows that treatment of all risk classes of APL with ATO and ATRA without chemotherapy is associated with excellent long-term outcomes in the real-world setting.

Comorbidity burden and outcomes of older adults with acute promyelocytic leukemia: a National Cancer Database analysis of 2221 patients

Association between comorbidity burden and patient outcomes has not been adequately investigated in acute promyelocytic leukemia (APL). We utilized the National Cancer Database to evaluate the association of the Charlson-Deyo Comorbidity Index (CCI) with one-month mortality and overall survival (OS) in adults ≥60 years with APL. One-month mortality was 16%, 24%, and 32%, and 3-year OS was 61%, 53%, and 38% for patients with CCI 0, 1, and ≥2, respectively. One-month mortality was higher for patients with CCI 1 (OR 1.67, 95% CI 1.29-2.16, p < .001) and CCI ≥ 2 (OR 2.31, 95% CI 1.70-3.13, p < .001) compared to patients with CCI 0. Patients with CCI 1 (HR 1.27, 95% CI 1.10-1.46, p < .001) and CCI ≥ 2 (HR 1.74, 95% CI 1.48-2.06, p < .001) had worse OS compared to patients with CCI 0. In conclusion, CCI is an independent predictor of survival outcomes in patients with APL.

Effects of peripheral blood leukocyte count and tumor necrosis factor-alpha on early death in acute promyelocytic leukemia

BACKGROUND

Early death remains a major factor in survival in APL. We aimed to analyze the risk factors for differentiation syndrome and early death in acute promyelocytic leukemia (APL).

METHODS

The clinical data of APL patients who were newly diagnosed at Mianyang Central Hospital from January 2013 to January 2022 were retrospectively analyzed.

RESULTS

Eighty-six newly diagnosed APL patients (37 males and 49 females) were included in this study. The median age was 46 (17-75) years. Sixty-one patients (70.9%) had low/intermediate-risk APL, and 25 patients (29.1%) had high-risk APL. The incidence of differentiation syndrome (DS) was 62.4%. The multivariate analysis showed that a peak white blood cell (WBC) count ≥16 × 10^9/L was an independent risk factor (OR = 11.000, 95% CI: 2.830-42.756, P = 0.001) for DS in all APL patients, while a WBC count ≥10 × 10^9/L on Day 5 was an independent risk factor for DS in low-intermediate risk APL patients (OR = 9.114, 95% CI: 2.384-34.849, P = 0.001). There were 31 patients (36.5%) with mild DS and 22 patients (25.9%) with severe DS. The multivariate analysis showed that WBC count ≥23 × 10^9/L at chemotherapy was an independent risk factor for severe DS (OR = 10.500, 95% CI: 2.344-47.034, P = 0.002). The rate of early death (ED) was 24.4% (21/86). The multivariate analysis showed that male gender (OR = 7.578,95% CI:1.136-50.551, P = 0.036), HGB < 65 g/L (OR = 16.271,95% CI:2.012-131.594, P = 0.009) and WBC count ≥7 × 10^9/L on Day 3(OR = 23.359,95% CI:1.825-298.959, P = 0.015) were independent risk factors for ED. The WBC count at diagnosis, WBC count on Day 3 and WBC count on Day 5 had moderate positive correlations with tumor necrosis factor-α (TNF-α) at diagnosis, and the correlation coefficients were 0.648 (P = 0.012), 0.615 (P = 0.033), and 0.609 (P = 0.035), respectively. The WBC count had no correlation with IL-6.

CONCLUSION

During induction treatment, cytotoxic chemotherapy may need to be initiated to reduce the risk of DS for APL patients with a low-intermediate risk WBC count ≥10 × 10^9/L on Day 5 or for all patients with a peak WBC count ≥16 × 10^9/L. Patients with WBC > 7 × 10^9/L on Day 3 have a higher risk of ED. Leukocyte proliferation is associated with TNF-α rather than IL-6, and TNF-α may be a potential biomarker for predicting ED.

Disparity in Utilization of Multiagent Therapy for Acute Promyelocytic Leukemia in the United States

BACKGROUND

Despite high rate of cure in acute promyelocytic leukemia (APL) in clinical trials, outcomes in real-world practice are dismal. We utilized National Cancer Database (NCDB) to explore utilization of multiagent therapy in APL and identify any disparities in treatment in real-world practices.

PATIENTS AND METHODS

NCDB categorizes use of systemic chemotherapy into single agent versus multiagent therapy. Some patients received hormonal therapy, immunotherapy, and unknown therapy; details of these treatments could not be ascertained. We therefore used multiple logistic regression analysis to evaluate effects of covariates on the probability of multiagent therapy use in 6678 patients.

RESULTS

Compared to patients >60 years, patients aged 0 to 18 years (hazard ratio[HR] 3.2, 95% confidence interval [CI] 1.8-5.5, P< .0001), 19 to 40 years (HR 1.6, 95% CI 1.03-2.54, P= .03), and 41 to 60 years (HR 1.6, 95% CI 1.3-1.9, P< .0001) were more likely to receive multiagent therapy. Patients with Charlson comorbidity index (CCI) of 0 (HR 1.6, 95% CI 1.2-2.3, P= .001) and CCI of 1 (HR 1.4, 95% CI 1.0-1.9, P= .04) had a higher likelihood of receiving multiagent therapy than patients with CCI ≥ 3. Patients treated at academic cancer centers, compared to those treated at community cancer center (HR 0.5, 95% CI 0.3-0.7, P= .001), comprehensive community cancer center (HR 0.7, 95% CI 0.6-0.8, P< .0001), and integrated network cancer center (HR 0.8, 95% CI 0.6-0.9, P= .02) were more likely to be treated with multiagent therapy. Compared to the patients with private insurance, those with Medicaid had increased likelihood (HR 1.2, 95% CI 1.0-1.4, P= .04) whereas uninsured patients had a lower likelihood of receiving multiagent therapy (HR 0.6, 95% CI 0.5-0.8, P= .0005).

CONCLUSION

To our knowledge, this study is the first and the largest scale analysis of treatment practices in APL in real-world practices. Our findings highlight significant disparities in treatment of APL based on age, insurance, and health-system factors.

Practice Patterns and Real-Life Outcomes for Patients with Acute Promyelocytic Leukemia in the United States

14% of newly diagnosed APL patients in the Vizient Clinical Data Base died during initial admission or were discharged to hospice.

Adverse outcomes were lower with guideline-concordant treatment, low-risk disease, higher hospital AML volume, and younger age.

Acute promyelocytic leukemia (APL) is associated with a favorable long-term prognosis if appropriate treatment is initiated promptly. Outcomes in clinical trials and population-based registries vary; potential explanations include a delay in treatment and lower adherence to guideline-recommended therapy in real-world practice. We used the Vizient Clinical Data Base to describe demographic characteristics, baseline clinical characteristics, and treatment patterns in patients newly diagnosed with APL during the study period of April 2017 to March 2020. Baseline white blood cell count was used to assign risk status and assess treatment concordance with National Comprehensive Cancer Network guidelines. Logistic regression models examined adjusted associations between patient, hospital, disease characteristics, and adverse outcomes (in-hospital death or discharge to hospice). Among 1464 patients with APL, 205 (14.0%) experienced an adverse outcome. A substantial subset (20.6%) of patients did not receive guideline-concordant regimens. Odds of adverse outcomes increased with failure to receive guideline-concordant treatment (odds ratio [OR], 2.31; 95% confidence interval [CI], 1.43-3.75; P = .001), high-risk disease (OR, 2.48; 95% CI, 1.53-4.00; P < .001), and increasing age (≥60 years: OR, 11.13; 95% CI, 4.55-27.22; P < .001). Higher hospital acute myeloid leukemia (AML) patient volume was associated with lower odds of adverse outcome (OR, 0.44; 95% CI, 0.20-0.99 [for ≤50 vs >200 AML patients per year]; P = .046). In conclusion, in this large database analysis, 14.0% of patients newly diagnosed with APL died or were discharged to hospice. A substantial proportion of patients did not receive guideline-concordant therapy, potentially contributing to adverse outcomes.

Alternative RNA Splicing-The Trojan Horse of Cancer Cells in Chemotherapy

Almost all transcribed human genes undergo alternative RNA splicing, which increases the diversity of the coding and non-coding cellular landscape. The resultant gene products might have distinctly different and, in some cases, even opposite functions. Therefore, the abnormal regulation of alternative splicing plays a crucial role in malignant transformation, development, and progression, a fact supported by the distinct splicing profiles identified in both healthy and tumor cells. Drug resistance, resulting in treatment failure, still remains a major challenge for current cancer therapy. Furthermore, tumor cells often take advantage of aberrant RNA splicing to overcome the toxicity of the administered chemotherapeutic agents. Thus, deciphering the alternative RNA splicing variants in tumor cells would provide opportunities for designing novel therapeutics combating cancer more efficiently. In the present review, we provide a comprehensive outline of the recent findings in alternative splicing in the most common neoplasms, including lung, breast, prostate, head and neck, glioma, colon, and blood malignancies. Molecular mechanisms developed by cancer cells to promote oncogenesis as well as to evade anticancer drug treatment and the subsequent chemotherapy failure are also discussed. Taken together, these findings offer novel opportunities for future studies and the development of targeted therapy for cancer-specific splicing variants.