Additional chromosome abnormalities in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and chemotherapy

A new chromosome translocation t(7;16)(q31,q22) change during an acute promyelocytic leukemia relapse

The translocation t(15;17), which results in the PML-RARα fusion gene, is a characteristic chromosomal translocation in acute promyelocytic leukemia (APL). But additional chromosome aberrations in APL are increasingly recognized. Here, we report on a 16-year-old APL patient who had an fms-related tyrosine kinase 3-internal tandem duplication (FLT3-ITD) and a 46,XY,t(15;17)(q22;q21)-16+mar karyotype at diagnosis. The patient achieved complete remission after induction therapy with all-trans retinoic acid and chemotherapy. But he soon relapsed presenting distinctive APL features in the bone marrow and leptomeninges and showing a chromosome translocation change involving chromosomes 7 and 16 besides t(15;17)(q22;q21). The new karyotype 46,XY,t(7;16)(q31;q22),t(15;17)(q22;q21) was determined. To the best of our knowledge, this is the first report of a de novo APL with a chromosome translocation t(7;16)(q31,q22) together with a t(15;17)(q22;q21) and FLT3-ITD mutation.

Current routine practice and clinico-pathological characteristics associated with acute promyelocytic leukemia in Korea

BACKGROUND

Acute promyelocytic leukemia (APL) can be life threatening, necessitating emergency therapy with prompt diagnosis by morphologic findings, immunophenotyping, cytogenetic analysis, or molecular studies. This study aimed to assess the current routine practices in APL and the clinico-pathologic features of APL.

METHODS

We reviewed the medical records of 48 Korean patients (25 men, 23 women; median age, 51 (20-80) years) diagnosed with APL in 5 university hospitals between March 2007 and February 2012.

RESULTS

The WBC count at diagnosis and platelet count varied from 0.4 to 81.0 (median 2.0)×10(9)/L and 2.7 to 124.0 (median 54.5)×10(9)/L, respectively. The median values for prothrombin time and activated partial thromboplastin time were 14.7 (11.3-44.1) s and 29 (24-62) s, respectively. All but 2 patients (96%) showed a fibrin/fibrinogen degradation product value of >20 µg/mL. The D-dimer median value was 5,000 (686-55,630) ng/mL. The t(15;17)(q22;q12 and PML-RARA fusion was found in all patients by chromosome analysis and/or multiplex reverse transcriptase-polymerase chain reaction (RT-PCR), with turnaround times of 8 (2-19) d and 7 (2-13) d, respectively. All patients received induction chemotherapy: all-trans retinoic acid (ATRA) alone (N=11, 26%), ATRA+idarubicin (N=25, 58%), ATRA+cytarabine (N=3, 7%), ATRA+idarubicin+cytarabine (N=4, 9%).

CONCLUSION

Since APL is a medical emergency and an accurate diagnosis is a prerequisite for prompt treatment, laboratory support to implement faster diagnostic tools to confirm the presence of PML-RARA is required.

Treatment-influenced associations of PML-RARα mutations, FLT3 mutations, and additional chromosome abnormalities in relapsed acute promyelocytic leukemia

Mutations in the all-trans retinoic acid (ATRA)-targeted ligand binding domain of PML-RARα (PRα/LBD+) have been implicated in the passive selection of ATRA-resistant acute promyelocytic leukemia clones leading to disease relapse. Among 45 relapse patients from the ATRA/chemotherapy arm of intergroup protocol C9710, 18 patients harbored PRα/LBD+ (40%), 7 of whom (39%) relapsed Off-ATRA selection pressure, suggesting a possible active role of PRα/LBD+. Of 41 relapse patients coanalyzed, 15 (37%) had FMS-related tyrosine kinase 3 internal tandem duplication mutations (FLT3-ITD+), which were differentially associated with PRα/LBD+ depending on ATRA treatment status at relapse: positively, On-ATRA; negatively, Off-ATRA. Thirteen of 21 patients (62%) had additional chromosome abnormalities (ACAs); all coanalyzed PRα/LBD mutant patients who relapsed off-ATRA (n = 5) had associated ACA. After relapse Off-ATRA, ACA and FLT3-ITD+ were negatively associated and were oppositely associated with presenting white blood count and PML-RARα type: ACA, low, L-isoform; FLT3-ITD+, high, S-isoform. These exploratory results suggest that differing PRα/LBD+ activities may interact with FLT3-ITD+ or ACA, that FLT3-ITD+ and ACA are associated with different intrinsic disease progression pathways manifest at relapse Off-ATRA, and that these different pathways may be short-circuited by ATRA-selectable defects at relapse On-ATRA. ACA and certain PRα/LBD+ were also associated with reduced postrelapse survival.

Acute promyelocytic leukemia: an experience on 95 greek patients treated in the all-trans-retinoic Acid era

Acute promyelocytic leukemia (APL) is highly curable with the combination of all-transretinoic acid (ATRA) and anthracycline based chemotherapy, but the percentage of early deaths remains high. In the present study, we report the clinical, immunophenotypic, cytogenetic and molecular characteristics and outcome of APL patients diagnosed and treated in various Hospitals of Greece and Cyprus.We describe the data of ninety-five APL patients who were diagnosed during the last 15 years. Seven (7.4%) newly diagnosed APL patients died due to intracranial hemorrhage within 72 hours of presentation. All but two patients were induced with ATRA alone or ATRA plus chemotherapy. The early death rate was 14.9%. After induction all 80 evaluable patients achieved complete hematologic remission. The cumulative incidence of relapse was 18.3%. Eight of the ten relapsed patients were successfully salvaged, while both patients with molecularly resistant disease died during salvage treatment. Overall survival (OS) at 5 years was 78.4% and disease free survival (DFS) 73.6%. In multivariate analysis of OS age over 60 years, DIC at diagnosis and marginally major hemorrhage at presentation were identified as adverse prognostic factors. In the subgroup of patients with available data on FLT3 mutation status (49 out of 94), ITD positivity also remained as an independent prognostic factor in the final model of OS, together with major hemorrhage and marginally high Sanz score. We found a close correlation between the CD2 expression and the development of the differentiation syndrome (DS). In conclusion, the main problem in managing patients with APL is still the high early death rate.

Therapy-related acute promyelocytic leukemia: observations relating to APL pathogenesis and therapy

Therapy-related acute promyelocytic leukemia (t-APL) is a well-recognized form of APL for which the underlying etiology has been well characterized. The pathogenesis of de novo (dn-APL) remains unknown; but epidemiologic studies have consistently identified increased body mass index (BMI), younger age, and ethnicity as possible risk factors. We analyzed demographics, clinical features, and treatment responses in a contemporary series of 64 patients treated with all-trans-retinoic acid and anthracycline-based therapy to assess for differences in these two etiologically distinct patient groups. Compared with patients with t-APL (n = 11), those with dn-APL (n = 53) had a greater median BMI (31.33 vs. 28.48), incidence of obesity (60.4% vs. 27.3%) (P = 0.04), and history of hyperlipidemia (45.3% vs. 18.2%) (P = 0.01). Fewer t-APL than dn-APL patients achieved complete remission at 63.6% vs. 92.5% respectively (P = 0.008). This was the result of a higher induction mortality rate of 36.4% vs. 7.5% respectively (P = 0.008). No cases of leukemic resistance were seen in either group. Overall survival (OS) was inferior in t-APL compared with dn-APL at 51% vs. 84%, respectively (P < 0.005), primarily as a result of higher induction mortality. Relapse occurred in nine patients (16.1%) overall, but no relapses occurred in the t-APL cohort. Our observations provide further support for the hypothesis that abnormalities in lipid homeostasis may in some way be of pathogenic importance in dn-APL. Therapy-related APL is sensitive to standard therapy with no cases of resistance or relapse seen. The inferior OS of the t-APL was due to induction mortality, possibly reflecting prior therapy.

Clinical impact of FLT3 mutation load in acute promyelocytic leukemia with t(15;17)/PML-RARA

BACKGROUND

Combined treatment with all-trans-retinoic acid and chemotherapy is extremely efficient in patients with acute promyelocytic leukemia with t(15;17)/PML-RARA, but up to 15% of patients relapse.

DESIGN AND METHODS

To further clarify the prognostic impact of parameters such as FLT3 mutations, we comprehensively characterized the relation between genetic features and outcome in 147 patients (aged 19.7-86.3 years) with acute promyelocytic leukemia.

RESULTS

Internal tandem duplications of the FLT3 gene (FLT3-ITD) were detected in 47/147 (32.0%) and tyrosine kinase domain mutations (FLT3-TKD) in 19/147 (12.9%) patients. FLT3-ITD or FLT3-TKD mutation status did not have a significant prognostic impact, whereas FLT3-ITD mutation load, as defined by a mutation/wild-type ratio of less than 0.5 was associated with trends to a better 2-year overall survival rate (86.7% versus 72.7%; P=0.075) and 2-year event-free survival rate (84.5% versus 62.1%, P=0.023) compared to the survival rates of patients with a ratio of 0.5 or more. Besides the t(15;17), an additional chromosomal abnormality was detected in 57 of 147 cases and did not show a significant impact on survival. White blood cell counts of 10×10(9)/L or less versus more than 10×10(9)/L were associated with a better 2-year overall survival rate (88.3% versus 69.4%, respectively; P=0.015), as was male sex (P=0.040). In multivariate analysis, only higher age had a significant adverse impact.

CONCLUSIONS

Prospective trials should further investigate the clinical impact of the FLT3-ITD/wild-type mutation load aiming to evaluate whether this parameter might be included in risk stratification in patients with acute promyelocytic leukemia.

Prognostic value of FLT3 mutations in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline monochemotherapy

BACKGROUND

Fms-like tyrosine kinase-3 (FLT3) gene mutations are frequent in acute promyelocytic leukemia but their prognostic value is not well established.

DESIGN AND METHODS

We evaluated FLT3-internal tandem duplication and FLT3-D835 mutations in patients treated with all-trans retinoic acid and anthracycline-based chemotherapy enrolled in two subsequent trials of the Programa de Estudio y Tratamiento de las Hemopatías Malignas (PETHEMA) and Hemato-Oncologie voor Volwassenen Nederland (HOVON) groups between 1996 and 2005.

RESULTS

FLT3-internal tandem duplication and FLT3-D835 mutation status was available for 306 (41%) and 213 (29%) patients, respectively. Sixty-eight (22%) and 20 (9%) patients had internal tandem duplication and D835 mutations, respectively. Internal tandem duplication was correlated with higher white blood cell and blast counts, lactate dehydrogenase, relapse-risk score, fever, hemorrhage, coagulopathy, BCR3 isoform, M3 variant subtype, and expression of CD2, CD34, human leukocyte antigen-DR, and CD11b surface antigens. The FLT3-D835 mutation was not significantly associated with any clinical or biological characteristic. Univariate analysis showed higher relapse and lower survival rates in patients with a FLT3-internal tandem duplication, while no impact was observed in relation to FLT3-D835. The prognostic value of the FLT3-internal tandem duplication was not retained in the multivariate analysis.

CONCLUSIONS

FLT3-internal tandem duplication mutations are associated with several hematologic features in acute promyelocytic leukemia, in particular with high white blood cell counts, but we were unable to demonstrate an independent prognostic value in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline-based regimens.

A rare case of microgranular acute promyelocytic leukemia associated with ider(17)(q10)t(15;17) in an old-age patient

We present a rare case of microgranular variant acute promyelocytic leukemia (APL) associated with ider(17)(q10)t(15;17)(q22;q12) of an old-age patient. The initial chromosome study showed a 46,XX,del(6)(?q21q25),der(15)t(15;17)(q22;q12),ider(17)(q10)t(15;17)[10]/47,sl,+ider(17)(q10)t(15;17)[3]/46,XX[16]. FISH signals from a dual color dual fusion translocation PML-RARA probe were consistent with the results of conventional cytogenetics. Because of the rarity of ider(17)(q10)t(15;17) in microgranular APL, further studies on both gene dosage effect of this chromosomal abnormality and the influence of ider(17)(q10)t(15;17) on clinical features such as prognosis, survival, and treatment response of APL cases are recommended.

Clinical significance of CD56 expression in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline-based regimens

The expression of CD56 antigen in acute promyelocytic leukemia (APL) blasts has been associated with short remission duration and extramedullary relapse. We investigated the clinical significance of CD56 expression in a large series of patients with APL treated with all-trans retinoic acid and anthracycline-based regimens. Between 1996 and 2009, 651 APL patients with available data on CD56 expression were included in 3 subsequent trials (PETHEMA LPA96 and LPA99 and PETHEMA/HOVON LPA2005). Seventy-two patients (11%) were CD56(+) (expression of CD56 in ≥ 20% leukemic promyelocytes). CD56(+) APL was significantly associated with high white blood cell counts; low albumin levels; BCR3 isoform; and the coexpression of CD2, CD34, CD7, HLA-DR, CD15, and CD117 antigens. For CD56(+) APL, the 5-year relapse rate was 22%, compared with a 10% relapse rate for CD56(-) APL (P = .006). In the multivariate analysis, CD56 expression retained the statistical significance together with the relapse-risk score. CD56(+) APL also showed a greater risk of extramedullary relapse (P < .001). In summary, CD56 expression is associated with the coexpression of immaturity-associated and T-cell antigens and is an independent adverse prognostic factor for relapse in patients with APL treated with all-trans-retinoic acid plus idarubicin-derived regimens. This marker may be considered for implementing risk-adapted therapeutic strategies in APL. The LPA2005 trial is registered at http://www.clinicaltrials.gov as NCT00408278.

Long-term survey of outcome in acute promyelocytic leukemia: a single center experience in 340 patients

The aims of this study are to investigate the outcome and prognostic factors influencing long-term survival on patients with acute promyelocytic leukemia (APL). A total of 340 APL patients admitted to the Department of Hematology from January 1988 to December 2009 were enrolled in this study. All patients received all-trans retinoic acid (ATRA) and/or arsenic trioxide (ATO) with anthracycline-based induction therapy. After three courses of consolidation chemotherapy, 279 patients received 2 years of maintenance therapy. Survival analyses were carried out using the Kaplan-Meier method and the Cox regression model. In total, 288 achieved CR with the CR rate of 84.7%, and 50 patients died during induction therapy. Univariate analysis identified the following three risk factors for hemorrhagic mortality: fibrinogen level (<1.0 g/l) (P = 0.0007), initial peripheral WBC count(>4 × 10(9)/l) (P = 0.0001), as well as the presence of coagulopathy(P < 0.0001). With a median follow-up of 49 (6-255) months, the estimated 5-year overall survival (OS) and relapse-free survival (RFS) were (89.0 ± 2.4)% and (83.7 ± 2.6)%, respectively. Cox regression analysis of the 290 patients showed initial WBC count, years of diagnosis, and the status of PML-RARα in remission seemed to be independent prognostic indicators for OS and RFS (P = 0.03, P < 0.01 and P = 0.0001, respectively). Cytogenetics in addition to above three variables remained significant for RFS (P = 0.01). Our retrospective observations suggest that the combination of ATRA and/or ATO with anthracycline-based therapy may have useful implications in the perspective of long-term prognosis for adult APL.

ider(17)(q10)t(15;17) associated with relapse and poor prognosis in a pediatric patient with acute promyelocytic leukemia

Although acute promyelocytic leukemia (APL) has been regarded as a serious medical emergency associated with disseminated intravascular coagulopathy or subsequent mortality, it is now considered a curable leukemia that is particularly sensitive to treatment with all-trans retinoic acid combined with chemotherapy. However, it is not clear whether additional chromosomal abnormalities in APL patients directly influence the prognosis or treatment response. ider(17)(q10)t(15;17)(q22;q21) has mostly been reported in adult APL patients, and only three cases of pediatric APL associated with ider(17)(q10)t(15;17) showing poor prognosis have been described in the literature. Here, we report the close follow-up (clinical and laboratory) data of a pediatric APL case associated with ider(17)(q10)t(15;17). This patient had APL relapse from the same clone 15 months after morphological remission. Furthermore, despite subsequent chemotherapy, the patient died 16 months after the initial APL diagnosis. Although based on a limited amount of data (four pediatric APL cases), such results in pediatric APL patients may provide important insight into the relationship between ider(17)(q10)t(15;17) and poor prognosis. However, further well-designed case-control studies are necessary to determine the treatment response and prognosis in pediatric or adult APL patients with ider(17)(q10)t(15;17).

Therapy-Related Myeloid Neoplasms in Patients With Acute Promyelocytic Leukemia Treated With All-Trans-Retinoic Acid and Anthracycline-Based Chemotherapy

Purpose

We analyzed the incidence, risk factors, and outcome of therapy-related myeloid neoplasms (t-MNs) in patients with acute promyelocytic leukemia (APL) in first complete remission (CR).

Patients and Methods

From 1996 to 2008, 1,025 patients with APL were enrolled onto three sequential trials (LPA96, LPA99, and LPA2005) of the Programa Español para el Tratamiento de Enfermedades Hematológicas and received induction and consolidation therapy with all-trans-retinoic acid (ATRA) and anthracycline-based chemotherapy.

Results

Seventeen of 918 patients who achieved CR developed t-MN (10 with < 20% and seven with ≥ 20% of bone marrow blasts) after a median of 43 months from CR. Partial and complete deletions of chromosomes 5 and 7 (nine patients) and 11q23 rearrangements (three patients) were the most common cytogenetic abnormalities. Overall, the 6-year cumulative incidence of t-MN was 2.2%, whereas in low-, intermediate-, and high-risk patients, the 6-year incidence was 5.2%, 2.1%, and 0%, respectively. Multivariate analysis identified age more than 35 years and lower relapse risk score as independent prognostic factors for t-MN. The median overall survival time after t-MN was 10 months.

Conclusion

t-MN is a relatively infrequent, long-term, and severe complication after first-line treatment for APL with ATRA and anthracycline-based regimens. Therapeutic strategies to reduce the incidence of t-MN are warranted.

ATRA and anthracycline-based chemotherapy in the treatment of childhood acute promyelocytic leukemia (APL): A 10-year experience in Tunisia

Reports on childhood APL from developing countries are scarce. We treated 65 APL with two consecutive trials combining ATRA and chemotherapy. Twenty (30.7%) were aged less than 20 years including 11 girls and 9 boys, with a median age of 12 years. Fever at presentation (P=0.002) and variant APL (P=0.044) were more frequent in children, while there were no significant difference between children and adults for WBC count, Sanz's score distribution and additional cytogenetic abnormalities. The CR rate was 95% (19/20) in children and 80% (36/45) in adults (P=0.13). Differentiation syndrome (DS) was less often observed in children (1/20) than in adults (13/45) (P=0.031). Two children relapsed and died during salvage therapy, and 2 died in CR from infection and from cardiac failure attributed to anthracyclines, while other children remained alive in CR. With a median follow-up of 4 years, 4-year EFS was 75% in children and 71.1% in adults (P=0.57), while 4-year OS was 75% in children vs. 73.3% in adults (P=0.72). Our results suggest that, even in the absence of optimal socio-economic condition, ATRA combined with anthracycline-based chemotherapy gives adequate results in childhood APL, as in adults.