Prognostic factors in childhood acute lymphoblastic leukemia

Poincaré Maps and Aperiodic Oscillations in Leukemic Cell Proliferation Reveal Chaotic Dynamics

Biological systems are dynamic systems featuring two very common characteristics; Initial conditions and progression over time. Conceptualizing this on tumour models it can lead to important conclusions about disease progression, as well as the disease's "starting point". In the present study we tried to answer two questions: (a) which are the evolving properties of proliferating tumour cells that started from different initial conditions and (b) we have attempted to prove that cell proliferation follows chaotic orbits and it can be described by the use of Poincaré maps. As a model we have used the acute lymphoblastic leukemia cell line CCRF-CEM. Measurements of cell population were taken at certain time points every 24 h or 48 h. In addition to the population measurements flow cytometry studies have been conducted in order to examine the apoptotic and necrotic rate of the system and also the DNA content of the cells as they progress through. The cells exhibited a proliferation rate of nonlinear nature with aperiodic oscillatory behavior. In addition to that, the (positive) Lyapunov indices and the Poincaré representations in phase-space that we performed confirmed the presence of chaotic orbits. Several studies have dealt with the complex dynamic behaviour of animal populations, but few with cellular systems. This type of approach could prove useful towards the understanding of leukemia dynamics, with particular interest in the understanding of leukemia onset and progression.

Analysis of outcomes and prognostic factors of acute lymphoblastic leukemia patients treated by MCP841 protocol: A regional cancer center experience

Background:

A dramatic improvement in the survival of acute lymphoblastic leukemia (ALL) patients in the last three decades has been observed. MCP 841 protocol is an old but effective tool with tolerable toxicities. The objective of this study was to estimate the relapse-free survival of ALL patients treated uniformly with MCP 841 protocol on the basis of various prognostic factors.

Materials and Methods:

The study design was retrospective and it was conducted in a regional cancer center of Northwest India. Three hundred and ten ALL patients who underwent treatment with MCP 841 protocol and regular follow-up for up to 5 years were selected for this study. Relapse-free survival was calculated by Kaplan–Meier analysis and Cox regression analysis was used to calculate the hazards ratio (HR) using Statistical Package for the Social Sciences (SPSS) software for windows version 20.0.

Results:

Fifty-four percent patients were <15 years of age and 69% were males. 53.2% patients were in remission at the end of 5 years of starting the treatment. Relapse-free survival at 5 years by Kaplan–Meir analysis for B-cell ALL was 62% [HR 0.67 {95% confidence interval (CI) 0.47-0.95}] with patients with unknown lineage taken as reference] while for T cell it was 28% [HR 1.41 (95% CI 1.19-1.63), P 0.001]. Patients with total leukocyte count (TLC) <1 lakh/cmm at presentation, relapse-free survival was 68% and those with TLC >1 lakh/cmm had 41% survival [HR 2.14 (1.76-2.48) with, P < 0.001].

Conclusion:

MCP 841 protocol is a useful tool for the treatment of ALL in children when more aggressive protocols can not be used.

Combination of prednisolone and low dosed dexamethasone exhibits greater in vitro antileukemic activity than equiactive dose of prednisolone and overcomes prednisolone drug resistance in acute childhood lymphoblastic leukemia

INTRODUCTION

Glucocorticoids, particularly prednisone/ prednisolone and dexamethasone, play a prominent role in the treatment of pediatric patients with acute lymphoblastic leukemia due to their ability to induce apoptosis in susceptible cells. Current therapeutic protocols use prednisone for both the prophase and the induction phase of the therapy because the greater antileukemic activity of dexamethasone is compromised by its high frequency of serious adverse reactions.

AIM

To compare, for the first time, the in vitro antileukemic activity of prednisolone alone to that of a combination of prednisolone and dexamethasone using dexamethasone at a very low and presumably safe dosage (1/50 w/w).

METHODS

Lymphoblasts were isolated from bone marrow and/or blood samples from children with newly diagnosed acute lymphoblastic leukemia. The cytotoxic activity of prednisolone, dexamethasone and the prednisolone/dexamethasone combination against isolated leukemia cells was analyzed using the MTT cytotoxicity assay.

RESULTS

We observed differences in the in vitro antileukemic activity of prednisolone and dexamethasone in 21% of the tested patients. 3% of the children were prednisolone sensitive but dexamethasone resistant, while 18% were prednisolone resistant and dexamethasone sensitive. 32% were sensitive to both glucocorticoids and 18% were resistant to both. Cells from patients with good in vivo responses to prednisone monotherapy were more responsive to prednisolone in vitro than were cells from patients with poor prednisone responses (P<0.07). Importantly, we demonstrated that the use of even a minimal dose (1/50 w/w) of dexamethasone with prednisolone dramatically increases the in vitro anti-leukemic activity of prednisolone (P<0.0006).

CONCLUSION

The high inter-individual variability of acute lymphoblastic leukemia responses to glucocorticoids suggest that either patients should be selected for prednisone or dexamethasone treatment on the basis of predictive biomarkers or that prednisone should be used directly in combination with a very low and safe dose of dexamethasone to potentiate its antileukemic activity. The latter option is likely to be cheaper and more efficient, and therefore warrants further clinical investigation to assess its efficacy and safety in treating childhood acute lymphoblastic leukemia.

Early chemosensitivity of normal hematopoietic cells and malignant lymphoblasts predicts relapse in childhood acute lymphoblastic leukemia

For the last 30 years, numerous clinical and biological pretreatment risk factors have been utilized for risk-based treatment assignment in childhood acute lymphoblastic leukemia (ALL). However, with improved chemotherapy regimens, many of these traditional prognostic factors have lost clinical significance. We aimed to improve relapse prediction in children with ALL through evaluation of the early chemosensitivity of normal and malignant cells and to determine the relationship between such chemosensitivity and risk of relapse. We retrospectively analyzed a cohort of 60 children with newly diagnosed ALL of whom 40 patients were in complete remission for at least 4 years and 20 patients relapsed during or following treatment. Time to peripheral blood blast clearance (PBBC) was used as a measure of chemosensitivity of malignant lymphoblasts while end-of-induction complete blood count (CBC) parameters were used as a measure of chemosensitivity of normal hematopoietic cells. Our results showed that longer time to PBBC and lower end-of-induction total leukocyte count (TLC) and absolute neutrophil count (ANC) were significantly associated with increased risk of relapse. In conclusion, time to PBBC and end-of-induction TLC and ANC are important predictors of relapse and should be used to modify the intensity of chemotherapy at earlier time points during the course of treatment. A wider prospective, randomized, controlled trial is required to confirm our results.

Overt testicular disease at diagnosis in childhood acute lymphoblastic leukemia: prognostic significance and role of testicular irradiation

OBJECTIVE

To analyze the prognostic impact of overt testicular disease (OTD) at diagnosis and role of testicular irradiation in the same.

METHODS

Data of 579 boys treated at our center over 16 years was reviewed.

RESULTS

Fourteen (2.4%) males had OTD. 10 (71.4%) of these had high-risk disease. Patients with OTD, had a significantly higher incidence of mediastinal-adenopathy (p=0.001), hyperleucocytosis (p=0.004) and CNS disease at presentation (p<0.0001) compared to patients in continuous complete remission (CCR). 4 of the 11 patients with OTD, who opted for therapy, had relapse; 2 are in CCR. Although, survival in patients with OTD was inferior (p=0.183) compared to patients without OTD, it was not an independent prognostic factor (p=0.47). In the entire study cohort, symptom-diagnosis interval (p=0.006), white cell (p=0.001) and platelet count (p=0.001) at presentation were significantly associated with survival (Cox multivariate regression analysis).

CONCLUSIONS

OTD was not an independent prognostic factor, despite association with high-risk features. Survival outcome was inferior. The observations indicate the need of revaluation of the present protocol with incorporation of intermediate dose and subsequently high-dose methotrexate (after assessment for toxicity and tolerance), risk-stratified therapy and plausibly omission of testicular irradiation.

Pattern of relapse in childhood ALL: challenges and lessons from a uniform treatment protocol

This retrospective analysis of 254 children less than 15 years of age treated with MCP-841 protocol from June 1992 to June 2002 was undertaken to identify the pattern of relapse and determine management lacunae. Two hundred twenty-three (87.8%) children achieved a complete remission of whom 40 (17.9%) relapsed. The mean age of relapsed patients was 6.5 years. The male/female ratio was 9:1. There were 23 (57.5%) isolated bone marrow (BM), 7 (17.5%) isolated central nervous system (CNS), 2 (5%) isolated testicular, 5 (12.5%) BM+testes and 1 each of BM+CNS, CNS+testes, and isolated bone relapses. Twenty-seven children (67.5%) relapsed on-therapy whereas 13 (32.5%) relapsed posttherapy. All 9 CNS relapses occurred on-therapy whereas 5/8 (62.5%) of testicular relapses occurred posttherapy. Lymphadenopathy was the only significant predictor for relapse. High-risk features such as age less than 1 year and greater than 10 years (P=0.047) and white cell count greater than 50.0 x 10(9)/L (P=0.044) were significantly more frequent in patients with early on-therapy relapse than in patients with off-therapy relapse. The overall survival in the entire study cohort was 67+/-3.5%. Modest survival outcome, relapse while on chemotherapy and the higher incidence of CNS and testicular relapse indicate the need for reappraisal of our treatment protocol. There is a need of identifying risk factors and high-risk groups in our set of patients and risk-stratified intensification of chemotherapy in them.

Acute lymphoblastic leukemia masquerading as juvenile rheumatoid arthritis: diagnostic pitfall and association with survival

Acute lymphoblastic leukemia (ALL) often presents with osteoarthritic manifestations which may lead to misdiagnosis with juvenile rheumatoid arthritis (JRA). This study was designed to identify ALL patients with initial diagnosis of JRA, compare their clinicolaboratory characteristics and outcome with other ALL patients treated at our center. Case records of 762 patients with ALL were analyzed. Information regarding the clinical-demographic profile, therapy and outcome were recorded. Of the children, 49 (6.4%) had initial presentation mimicking JRA. Asymmetric oligoarthritis was the most common pattern of joint involvement. Majority presented with fever, pallor, arthritis, night pain, and bone pain. None of the routine prognostic factors including age, gender, lymphadenopathy, hepatosplenomegaly, total leukocytes count (TLC), and platelet count were significantly associated with relapse/death. The mean symptom-presentation interval (SPI), hemoglobin was significantly higher whilst the TLC was significantly lower in these patients compared to other ALL patients. The 5 year overall-survival was better than other patients with ALL (p = 0.06, by logrank test). Significantly longer SPI in these patients underscores the need for prompt and early investigations to rule out ALL in patients of JRA with atypical features and pointers of ALL. Children with ALL-mimicking JRA may belong to a subgroup of ALL with a better prognosis.

Survival outcome in childhood ALL: experience from a tertiary care centre in North India

BACKGROUND

Survival of children with ALL, in developing nations has not kept pace with cure rates in developed countries. Our study was designed to assess survival data and identify risk factors.

PROCEDURE

Data of 762 patients with ALL were analyzed. Information regarding the clinical-demographic profile, therapy and course of illness were recorded. Status and duration at last follow-up were utilized to generate Kaplan-Meier survival curves.

RESULTS

The mean age was 5.7 +/- 0.23 years (M/F, 3.2:1). Parents of 230 (30.2%) patients opted for no therapy. There were 68 and 60 deaths in induction and remission phases respectively. Besides these, 111 children either defaulted therapy or were lost to follow up. Relapsed disease was documented in 125 cases. The 5-year OS and EFS was 46% and 43% respectively. Survival analysis, using the Cox multivariate regression, for gender (P = 0.659, CI: 0.852-1.161), age (P = 0.943, CI: 0.725-1.225), symptom-diagnosis interval (P = 0.002, CI: 1.116-1.668), WCC (P < 0.001, CI: 1.353-1.814) and platelet count (P = 0.001, CI: 0.546-0.849) was performed. Bulk disease (P = 0.049, CI: 0.428-0.986), mediastinal adenopathy (P = 0.045, CI: 1.040-3.697), WCC (P = 0.016, CI: 1.395-2.691), platelet count (P = 0.031, CI: 0.431-0.967) and administration of 2 intensification blocks (P = 0.012, CI: 0.624-0.940) were found to be significant predictors of outcome by multivariate analysis.

CONCLUSIONS

The management of ALL requires financial resources and access to quality supportive care. One third of our patients opted for no therapy. The other problem areas were a high proportion of therapy defaulters, lost to follow up and infection related deaths during induction and remission phases. The introduction of remedial measures for resolving the difficulties identified would hopefully improve cure rates in ALL in developing nations.

Monitoring treatment response of childhood precursor B-cell acute lymphoblastic leukemia in the AIEOP-BFM-ALL 2000 protocol with multiparameter flow cytometry: predictive impact of early blast reduction on the remission status after induction

Treatment response is a strong outcome predictor for childhood acute lymphoblastic leukemia (ALL). Here, we evaluated the predictive impact of flow cytometric blast quantification assays (absolute blast count, BC, and blast reduction rate, BRR) in peripheral blood (pB) and/or bone marrow (BM) at early time points of induction therapy (days 0, 8 and 15) on the remission status in the AIEOP-BFM-ALL 2000 protocol. At the single parameter level (905 patients), the strongest predictive parameter for the remission status as a dichotomous minimal residual disease (MRD) parameter (positive/negative) has been provided by the BC at day 15 in BM (cutoff: 17 blasts/microl; 50 vs 15%; odds ratio: 5.6; 95% confidence interval: 4.1-7.6, P<0.001), followed by the BRR at day 15 in BM and by the BC at day 8 in pB (odds ratios: 3.8 and 2.6, respectively). In the multiple regression analysis (440 patients), BC in pB (d0 and d8) and in BM (d15) as well as BRR at day 8 in pB provided significantly contributing variables with an overall correct prediction rate of 74.8%. These data show that the quantitative assessment of early response parameters, especially absolute BCs at day 15 in BM, has a predictive impact on the remission status after induction therapy.