Duration of second complete remission compared with first complete remission in patients with acute myeloid leukemia. Eastern Cooperative Oncology Group

Cancer: slaying the nine-headed Hydra

Modern medicine continues to evolve, and the treatment armamentarium for various diseases grows more individualized across a breadth of medical disciplines. Cure rates for infectious diseases that were previously pan-fatal approach 100% because of the identification of the specific pathogen(s) involved and the use of appropriate combinations of drugs, where needed, to completely extinguish infection and hence prevent emergence of resistant strains. Similarly, with the assistance of technologies such as next-generation sequencing and immunomic analysis as part of the contemporary oncology armory, therapies can be tailored to each tumor. Importantly, molecular interrogation has revealed that metastatic cancers are distinct from each other and complex. Therefore, it is conceivable that rational personalized drug combinations will be needed to eradicate cancers, and eradication will be necessary to mitigate clonal evolution and resistance.

Survival prognostic factors in patients with acute myeloid leukemia using machine learning techniques

This paper identifies prognosis factors for survival in patients with acute myeloid leukemia (AML) using machine learning techniques. We have integrated machine learning with feature selection methods and have compared their performances to identify the most suitable factors in assessing the survival of AML patients. Here, six data mining algorithms including Decision Tree, Random Forrest, Logistic Regression, Naive Bayes, W-Bayes Net, and Gradient Boosted Tree (GBT) are employed for the detection model and implemented using the common data mining tool RapidMiner and open-source R package. To improve the predictive ability of our model, a set of features were selected by employing multiple feature selection methods. The accuracy of classification was obtained using 10-fold cross-validation for the various combinations of the feature selection methods and machine learning algorithms. The performance of the models was assessed by various measurement indexes including accuracy, kappa, sensitivity, specificity, positive predictive value, negative predictive value, and area under the ROC curve (AUC). Our results showed that GBT with an accuracy of 85.17%, AUC of 0.930, and the feature selection via the Relief algorithm has the best performance in predicting the survival rate of AML patients.

Characteristics predicting outcomes of allogeneic stem-cell transplantation in relapsed acute myelogenous leukemia

BACKGROUND

Allogeneic hematopoietic stem-cell transplantation (ahsct) is associated with significant morbidity and mortality, but it can cure carefully selected patients with acute myeloid leukemia (aml) in second remission (cr2). In a cohort of patients with aml who underwent ahsct in cr2, we determined the pre-transplant factors that predicted for overall survival (os), relapse, and non-relapse mortality. We also sought to validate the prognostic risk groups derived by Michelis and colleagues in this independent population.

METHODS

In a retrospective chart review, we obtained data for 55 consecutive patients who underwent ahsct for aml in cr2. Hazard ratios were used to describe the independent effects of pre-transplant variables on outcome, and Kaplan-Meier curves were used to assess outcomes in the three prognostic groups identified by Michelis and colleagues.

RESULTS

At 1, 3, and 5 years post-transplant, os was 60%, 45.5%, and 37.5% respectively. Statistically significant differences in os, relapse mortality, and non-relapse mortality were not identified between the prognostic risk groups identified by Michelis and colleagues. Women were less likely than men to relapse, and a modified European Society for Blood and Marrow Transplantation (mebmt) score of 3 or less was associated with a lower non-relapse mortality.

CONCLUSIONS

The 37.5% 5-year os in this cohort suggests that, compared with other options, ahsct offers patients with aml in cr2 a better chance of cure. Our study supports the use of the mebmt score to predict non-relapse mortality in this population.

Management of Relapsed/Refractory Acute Myeloid Leukemia in the Elderly: Current Strategies and Developments

Elderly patients with acute myeloid leukemia (AML) who are refractory to or relapse following frontline treatment constitute a poor-risk group with a poor long-term outcome. Host-related factors and unfavorable disease-related features contribute to early treatment failures following frontline therapy, thus making attainment of remission and long-term survival with salvage therapy particularly challenging for elderly patients. Currently, no optimal salvage strategy exists for responding patients, and allogeneic hematopoietic stem cell transplant is the only curative option in this setting; however, the vast majority of elderly patients are not candidates for this procedure due to poor functional status secondary to age and age-related comorbidities. Furthermore, the lack of effective salvage programs available for elderly patients with recurrent AML underscores the need for therapies that consistently yield durable remissions or durable control of their disease. The purpose of this review was to highlight the currently available strategies, as well as future strategies under development, for treating older patients with recurrent AML.

Fractionated gemtuzumab ozogamicin and standard dose cytarabine produced prolonged second remissions in patients over the age of 55 years with acute myeloid leukemia in late first relapse

Gemtuzumab ozogamicin (fGO), a humanized anti-CD33 monoclonal antibody linked to calicheamicin in combination with intensive chemotherapy gives high response rates in adult acute myeloid leukemia (AML) patients in relapse. However, reduced intensity chemotherapy in combination with fractionated GO has not been tested in aged relapsing patients. Patients from our institution with CD33+ AML aged 55 years or more in first late relapse (≥ 6 months) were proposed participation in a GO compassionate use program. Induction therapy consisted in fractionated GO (fGO; 3 mg/m², days 1, 4, 7) with standard-dose cytarabine (200 mg/m² /day, 7 days). Patients were consolidated with two courses of GO and intermediate dose cytarabine. Twenty-four patients (median age 68 years) received fGO with cytarabine. Median follow-up was 42 months. The response rate was 75%, including complete remission (CR) in 16 patients and CR with incomplete platelet recovery (CRp) in two patients. Two-year overall survival (OS) was 51% (95% CI: 28-69) and 2 years relapse-free survival (RFS) was 51% (95%CI: 25-72). Duration of second CR (CR2) was longer than first CR (CR1) in 9 out of 18 patients. Minimal residual disease (MRD) was negative in evaluable patients in CR2, particularly in NPM1 mutated cases. Toxicity was in line with that of the same fractionated single agent GO schedule. Fractionated GO with low intensity chemotherapy produced high response rates and prolonged CR2 in aged AML patients in first late relapse.

A dendritic cell vaccine pulsed with autologous hypochlorous acid-oxidized ovarian cancer lysate primes effective broad antitumor immunity: from bench to bedside

PURPOSE

Whole tumor lysates are promising antigen sources for dendritic cell (DC) therapy as they contain many relevant immunogenic epitopes to help prevent tumor escape. Two common methods of tumor lysate preparations are freeze-thaw processing and UVB irradiation to induce necrosis and apoptosis, respectively. Hypochlorous acid (HOCl) oxidation is a new method for inducing primary necrosis and enhancing the immunogenicity of tumor cells.

EXPERIMENTAL DESIGN

We compared the ability of DCs to engulf three different tumor lysate preparations, produce T-helper 1 (TH1)-priming cytokines and chemokines, stimulate mixed leukocyte reactions (MLR), and finally elicit T-cell responses capable of controlling tumor growth in vivo.

RESULTS

We showed that DCs engulfed HOCl-oxidized lysate most efficiently stimulated robust MLRs, and elicited strong tumor-specific IFN-γ secretions in autologous T cells. These DCs produced the highest levels of TH1-priming cytokines and chemokines, including interleukin (IL)-12. Mice vaccinated with HOCl-oxidized ID8-ova lysate-pulsed DCs developed T-cell responses that effectively controlled tumor growth. Safety, immunogenicity of autologous DCs pulsed with HOCl-oxidized autologous tumor lysate (OCDC vaccine), clinical efficacy, and progression-free survival (PFS) were evaluated in a pilot study of five subjects with recurrent ovarian cancer. OCDC vaccination produced few grade 1 toxicities and elicited potent T-cell responses against known ovarian tumor antigens. Circulating regulatory T cells and serum IL-10 were also reduced. Two subjects experienced durable PFS of 24 months or more after OCDC.

CONCLUSIONS

This is the first study showing the potential efficacy of a DC vaccine pulsed with HOCl-oxidized tumor lysate, a novel approach in preparing DC vaccine that is potentially applicable to many cancers.

Ara-C, Idarubicine and Gentuzumab Ozogamicin (AIM) as Salvage Treatment in Advanced Acute Myeloid Leukemia Patients

Long-term survival of relapsed/refractory acute myeloid leukemia (AML) remains a major problem, particularly in patients not eligible for transplantation.

We hereby evaluated the feasibility and efficacy of adding Gemtuzumab Ozogamicin to salvage chemotherapy (Ara-C, Idarubicine, Peg-Filgrastim) in relapsed/refractory AML. The main endpoints were: the rate of complete remissions (CR) and the proportion of patients capable of undergoing a stem cell transplant.

Fourty-two patients were enrolled. The overall CR rate was 76% and no induction deaths were reported. In 56% of patients, a transplant procedure could be performed. The treatment schedule proved feasible and well tolerated, providing a high CR rate and a useful bridge to transplant.

Prognostic factors and outcomes of adult patients with acute myeloid leukemia after first relapse

BACKGROUND

Patients with acute myeloid leukemia who are treated with conventional chemotherapy still have a substantial risk of relapse; the prognostic factors and optimal treatments after relapse have not been fully established. We, therefore, retrospectively analyzed data from patients with acute myeloid leukemia who had achieved first complete remission to assess their prognosis after first relapse.

DESIGN AND METHODS

Clinical data were collected from 70 institutions across the country on adult patients who were diagnosed with acute myeloid leukemia and who had achieved a first complete remission after one or two courses of induction chemotherapy.

RESULTS

Among the 1,535 patients who were treated with chemotherapy alone, 1,015 relapsed. Half of them subsequently achieved a second complete remission. The overall survival was 30% at 3 years after relapse. Multivariate analysis showed that achievement of second complete remission, salvage allogeneic hematopoietic cell transplantation, and a relapse-free interval of 1 year or longer were independent prognostic factors. The outcome after allogeneic transplantation in second complete remission was comparable to that after transplantation in first complete remission. Patients with acute myeloid leukemia and cytogenetic risk factors other than inv(16) or t(8;21) had a significantly worse outcome when they did not undergo salvage transplantation even when they achieved second complete remission.

CONCLUSIONS

We found that both the achievement of second complete remission and the application of salvage transplantation were crucial for improving the prognosis of patients with acute myeloid leukemia in first relapse. Our results indicate that the optimal treatment strategy after first relapse may differ according to the cytogenetic risk.

Long-term disease-free survival after gemtuzumab, intermediate-dose cytarabine, and mitoxantrone in patients with CD33(+) primary resistant or relapsed acute myeloid leukemia

PURPOSE

To determine the antitumor activity and safety of a combination of gemtuzumab ozogamicin (GO), intermediate-dose cytarabine, and mitoxantrone (MIDAM) in patients with refractory or relapsed CD33(+) acute myeloid leukemia (AML).

PATIENTS AND METHODS

We treated 62 patients with refractory (n = 18) or relapsed (n = 44) CD33(+) AML. Median age was 55.5 years. Salvage regimen consisted of GO 9 mg/m(2) on day 4, cytarabine 1 g/m(2) every 12 hours on days 1 through 5, and mitoxantrone 12 mg/m(2)/d on days 1 through 3. Median follow-up time was 26.5 months.

RESULTS

Thirty-one patients (50%) achieved complete remission (CR), and eight patients (13%) had CR with delayed platelet recovery (CRp); the overall response (OR; CR + CRp) rate was 63%. A significantly higher OR rate was achieved in patients who had relapsed versus refractory AML (73% v 39%, respectively; P = .007) and patients with CD33 expression more than 98% of the blast population versus less than 98% (79% v 52.3%, respectively; P = .03). The overall, event-free, and disease-free survival rates were 41%, 33%, and 53% at 2 years, respectively. Leukocytosis more than 20,000/microL at MIDAM therapy, high-risk cytogenetics, and absence of postremission therapy were adverse prognostic factors. Age, disease status, and/or CD33 expression did not influence survival parameters. Four early toxic deaths occurred; a grade 3 to 4 hyperbilirubinemia rate of 16% was observed, and two patients had veno-occlusive disease (3%).

CONCLUSION

The MIDAM regimen seems to be an effective salvage regimen for refractory/relapsed CD33(+) AML patients. These encouraging results support the need for a randomized phase III trial before considering this combination of GO and chemotherapy as superior or the standard of care treatment for refractory/relapsed CD33(+) AML patients.

Prognostic Index for Adult Patients With Acute Myeloid Leukemia in First Relapse

Purpose

The treatment of acute myeloid leukemia (AML) in first relapse is associated with unsatisfactory rates of complete responses that usually are short lived. Therefore, a clinically useful prognostic index can facilitate therapeutic decision making and evaluation of investigational treatment strategies at relapse of AML.

Patients and Methods

A prognostic score is presented based on the multivariate analysis of 667 AML patients in first relapse among 1,540 newly diagnosed non-M3 AML patients (age 15 to 60 years) entered onto three successive Dutch-Belgian Hemato-Oncology Cooperative Group and the Swiss Group for Clinical Cancer Research Collaborative Group trials.

Results

Four clinically relevant parameters are included in this index (ie, length of relapse-free interval after first complete remission, cytogenetics at diagnosis, age at relapse, and whether previous stem-cell transplantation was performed). Using this stratification system, three risk groups were defined: a favorable prognostic group A (overall survival [OS] of 70% at 1 year and 46% at 5 years), an intermediate-risk group B (OS of 49% at 1 year and 18% at 5 years), and a poor-risk group C (OS of 16% at 1 year and 4% at 5 years).

Conclusion

The prognostic index estimates the outcome of AML patients in first relapse using four commonly applied clinical parameters and might identify patients who are candidates for salvage and investigational therapy.

The therapy of relapsed acute leukaemia in adults

Although the cure of acute leukaemia has improved significantly, many patients will still relapse and die. The unraveling of the molecular pathogenesis of acute leukaemia has lead to the identification of new prognostic factors and improved the detection of minimal residual disease. The treatment of relapsed acute leukaemia with chemotherapy remains unsatisfactory. Allogeneic or autologous blood and marrow transplant (BMT) can cure a subset of patients with relapsed acute leukaemia. The identification of the graft-vs-leukaemia (GVL) effect has lead to the development of donor lymphocyte infusions to re-induce remission in patients with relapsed leukaemia after allogeneic BMT and also stimulated the development of the less toxic nonmyeloablative allogeneic transplant approach. The identification of molecular targets of therapy and the development of monoclonal antibody-directed therapy has generated optimism. It is possible that combinations of chemotherapy, molecularly directed therapy, and immunotherapy may be combined to cure an increasing proportion of patients with acute leukaemia.

Phase II trial of arsenic trioxide in relapsed and refractory acute myeloid leukemia, secondary leukemia and/or newly diagnosed patients at least 65 years old

The prognosis for patients with relapsed/refractory AML, secondary leukemia and AML in older adults is extremely poor. An appealing alternative approach to intensive cytotoxic chemotherapy is to induce apoptosis with a novel agent. There is in vitro evidence that arsenic trioxide (ATO) has anti-proliferative and pro-apoptotic effects on myeloid leukemia cell lines. To evaluate efficacy and toxicities of ATO, we conducted a phase II trial including subjects with relapsed/refractory or secondary AML or age > or = 65 years with de novo disease. Eleven subjects were entered with a median age of 77 years (56-90) and a median total dose of ATO of 415.55 mg (91.5-793) with a daily dose of 0.25 mg/kg. Median survival following the first dose of ATO was 2.25 months (0.4-19). Myelosuppression was the major adverse effect, most likely due to disease progression rather than drug-related. All subjects had progressive disease. There was no direct treatment-related mortality. Based on this study, we do not recommend single agent ATO as a treatment option for AML.

Expression of co-stimulatory molecules on acute myeloid leukaemia blasts may effect duration of first remission

Many solid tumours have been shown to lack expression of either of the immune co-stimulatory molecules CD80 (B7.1) or CD86 (B7.2), which is thought to be one of the ways in which tumours may escape immune recognition. We have examined the surface expression of CD80, CD86, human leucocyte antigen (HLA) class I and II, CD11a, CD54, and CD58 on the blast cells from patients with acute myeloid leukaemia (AML) at presentation. CD80 was only rarely expressed on AML blasts and, in those leukaemic cells expressing CD80, the level of expression was low. In contrast, expression of CD86 was detected on the AML blasts in more than half of the samples tested and, in some cases, the level of expression was equivalent to that of mature monocytes and activated B lymphocytes. The percentage of leukaemic blasts expressing CD86 was higher in the M4 and M5 French-American-British (FAB) types, and expression of CD11a and HLA class II was higher in the M4 FAB type. There was no difference in expression of CD80, CD54, CD58, or HLA Class I between different FAB subgroups. There was no significant difference in duration of first remission with expression of CD80, CD86, CD11a, CD54 or HLA class II. However, when expression of CD80 and CD86 were considered together, a significantly longer duration of remission was found. We suggest that these molecules may play a role in immunosurveillance, resulting in prolonged remission in some patients treated for AML.

The search for optimal treatment in relapsed and refractory acute myeloid leukemia

Despite the significant progress in the treatment of AML during the last 5-10 years, 20-40% of patients still do not achieve remission with standard induction therapy. In addition, 50-70% of patients in CR are likely to relapse. A major limitation of successful AML therapy is intrinsic or acquired drug resistance. Several pharmacological inhibitors of mechanisms inducing chemoresistance in leukemic cells have been investigated. New cytotoxic drugs, agents with novel mechanisms of action, and new treatment strategies are currently being investigated. The management of refractory or relapsed AML patients is reviewed in this study.

Resonance in periodic chemotherapy: a case study of acute myelogenous leukemia

The effects of periodic chemotherapy administration are evaluated within the context of a G(0)model of the cell cycle. Parameters are estimated for normal bone marrow cells and malignant cells in acute myelogenous leukemia (AML). This model explicitly includes the resting G(0)phase and the feedback mechanism that recruits the cells back into the cell cycle. Periodic chemotherapy administration can induce resonance within our model under high cell kill rate where the average cell cycle times may change during the course of treatment, and therapeutic benefits from these resonances cannot be solely based on cell cycle times in untreated tissue. The depletion rate under chemotherapy and the regrowth rate may differ between the cell populations, and our analysis suggests that this favors the tumour cells. We were able to distinguish between the effects of cycle-non-specific, S -phase-specific and M -phase-specific drugs, and found that these can show differences in sharpness and location of the resonance phenomenon. We conclude that resonance chemotherapy (chronotherapy) is unlikely to be efficacious in the treatment of AML.