• Users Online: 564
  • Home
  • Print this page
  • Email this page
Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 6  |  Issue : 1  |  Page : 6-12

Clinical features and outcome of acute myeloid leukemia, a single institution experience in Saudi Arabia


1 King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
2 Department of Pathology, King Abdulaziz Medical City, Ministry of National Guard, Riyadh; King Abdullah International Medical Research Center, Riyadh; King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
3 Division of Adult Hematology, King Abdulaziz Medical City, Ministry of National Guard, Riyadh; King Abdullah International Medical Research Center, Riyadh; King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia

Date of Web Publication15-Apr-2015

Correspondence Address:
Mohsen Al Zahrani
King Saud Bin Abdulaziz University for Health Sciences
Saudi Arabia
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1658-5127.155171

Rights and Permissions
  Abstract 

Aim: Acute myeloid leukemia (AML) is a type of malignancy that is associated with a malignant alteration of normal hematopoietic stem cells in the bone marrow. The aim of this study was to study the demographics and pathological subtypes of AML, evaluate the response and outcome to different treatment modalities. Methods: This was a retrospective study of adult patients diagnosed with AML at King Abdulaziz Medical City - Riyadh, between 2006 and 2013. Data were retrieved from patients' files, electronic medical files and laboratory information system. Results: 91 patients were included in the study with a male dominance. M1 was the most common French-American-British subtype with 23 (32%) cases. Patients with intermediate-risk AML were the most common subgroup with 41 (48%) cases followed by high and low-risk subgroups, 29 (33%) and 16 (19%), respectively. 74 patients were treated with intensive chemotherapy, and 17 were on palliative chemotherapy or best supportive treatment. Remission rate was found to be 84% in patients who received induction chemotherapy while 41% of them relapsed. 93% of low-risk patients underwent complete remission (CR) compared to intermediate and high-risk patients (79% and 87% respectively), but it was not statistically significant (P = 0.4). The median follow-up was 19 months, with overall survival (OS) of 46% for all groups. The low-risk patients had the highest OS 57% compared to intermediate and high risk (52% and 36%, respectively), but it was not statistically significant (P = 0.3). 18 patients had been treated with allogeneic stem cell transplant and at a median follow-up of 17 months posttransplant the OS was 72%. Conclusion: This study shows M1 subtype to be the most common of AML in this population. In addition, the CR was better with similar survival rate as compared to other local and internationally published experiences. These results, albeit with its limitations, need to be confirmed in a prospective clinical trial or national disease registry.

Keywords: Acute myeloid leukemia, clinical and pathological features, Saudi Arabia, therapy outcome


How to cite this article:
Faleh AA, Al-Quozi A, Alaskar A, Zahrani MA. Clinical features and outcome of acute myeloid leukemia, a single institution experience in Saudi Arabia. J Appl Hematol 2015;6:6-12

How to cite this URL:
Faleh AA, Al-Quozi A, Alaskar A, Zahrani MA. Clinical features and outcome of acute myeloid leukemia, a single institution experience in Saudi Arabia. J Appl Hematol [serial online] 2015 [cited 2020 Aug 15];6:6-12. Available from: http://www.jahjournal.org/text.asp?2015/6/1/6/155171


  Introduction Top


Acute myeloid leukemia (AML) is a type of malignancy that is associated with a malignant alteration of the normal hematopoietic stem cells (HPSC) in the bone marrow (BM). [1],[2] The disease is characterized by an excessive proliferation of immature myeloid cell line, which leads to an accumulation of blast cells in the BM, blood, and organs such as spleen, liver, and rarely other organs. [1],[3] This is often followed by a decline in the number of normal blood cells. [1] According to the World Health Organization (WHO) criteria, the diagnosis of AML is established by demonstrating more than 20% of the BM by leukemic myeloid blasts. [4]

Acute myeloid leukemia is considered one of the most common types of cancers in the US with an incidence rate of 5/100,000. [3] According to the latest Cancer Incidence Report in Saudi Arabia for the year of 2009, there were 619 documented new cases of adult leukemia, which accounts for 6.3% of all types of adult cancers. Leukemia is considered the third most common malignancy to affect males and the fifth in females. 164 out of 619 leukemia patients were AML patients. [5] AML is considered an age-related malignancy with a mean age of 70 years at diagnosis. [1]

During the 1970's, a classification of AML was established by a group of experts called "The French-American-British (FAB) classification of AML." The classification divided AML into eight subtypes from M0 to M7 based on the morphology of blast cells and the degree of maturation of those cells. [6] Recently, the WHO classification of AML was based mainly on the genetic changes, the etiologic factors of AML, and the morphologic classification of the disease. This new classification gives better insight for the causes of the disease, options of therapy and prognosis of AML. [4]

In most cases of AML, the underlying etiologies are unknown but there are well-known risk factors that increase the risk of developing AML. Exposure to chemicals such as benzene and radioactive materials can increase the risk of developing AML. AML also can develop as a secondary disease to other hematological disorders such as myelodysplastic syndrome (MDS) or myeloproliferative neoplasia, such as chronic myelocytic leukemia, or to previous exposure to chemotherapy or radiation therapy used for treating other malignancies. [1]

Around 50-60% of newly diagnosed patients with AML will have recurrent cytogenetic abnormalities, which can determine the disease prognosis. [1] Immunophenotype of malignant cells can also affect the outcome and response to treatment, e.g. patients with positive CD56 have a bad prognosis. [7] The most common antigens expressed in AML patients were CD13, CD33, CD117, and myeloperoxidase (MPO). [8] However, the most common lymphoid markers co-expressed aberrantly in patients with AML were CD7, CD2, CD19, and CD22. [9] Literature reported from Saudi Arabia revealed limited data about the clinical, pathological features and immunophenotypes of all subtypes of AML. Hence, this study was undertaken at our institution.


  Methods Top


This study was conducted at King Abdulaziz Medical City (KAMC) in Riyadh. KAMC is a tertiary care center and JCI accredited with a bed capacity of more than 900 beds. It provides all types of care to all National Guard soldiers and their families, starting from primary health care up to tertiary specialized care. The oncology center was established in 2006 and has all oncology services including hematology and HPSC transplant service. This is a case series retrospective study that included all adult patients diagnosed with any AML subtypes from 2006 to 2013. Patients with mixed phenotypes leukemia were excluded. The data was retrieved manually from medical records, and electronically from the hospital electronic medical record system (Quadramed) for clinical data and the laboratory information system for flow cytometry and immunophenotype results. The data collected included patients' demographics data, genetic abnormalities of the disease, immunophenotypes and FAB pathologic subtypes of the disease, treatment protocol and response to treatment. Patients were classified according to the WHO criteria as low risk if they had t (15,17)/t (8,21)/t (16,16)/and inv. 16, or as intermediate risk if they had normal cytogenetic or cytogenetic abnormalities other than those seen in low-risk or high-risk categories and as high risk if they were secondary AML/complex cytogenetic/Monosomy 5 or 7 and relapsed refractory cases. One limitation of this classification was the lack of known AML molecular mutations in the risk stratification. The molecular genetic tests were either not done or not available for the majority of patients.

About 10-20 patients are diagnosed yearly with AML at KAMC, Riyadh, and the study included all adult patients with AML between the years 2006 and 2013. The whole population was studied, so no sampling was required. Data were entered into excel spreadsheets and then managed with SPSS (IBM SPSS version 16.0) using descriptive methods: Mean, standard deviation for numerical variables, percentages, frequencies for all categorical variables. Chi-square test was used for comparing the relapse, remission, and mortality among subgroups and Kaplan-Meier graph for determining the survival rate. The study was approved by the IRB at King Saud Bin Abdulaziz University for health sciences.


  Results Top


There were 91 patients who qualified the inclusion criteria [Table 1]. There is a higher occurrence of the disease in male patients compared to female with a percentage of 58% and a mean age of 48.5 ± 20.6 years old for both genders. The median of presenting white blood cell in peripheral blood was 14 × 10 9 /L and blasts in BM were 65 × 10 9 /L. There were 72 patients with defined FAB subtypes, the most common FAB subtype was M1 in 23 patients (32%), followed by M2 in 19 patients (26%); there were no M6 among these AML patients. There were 86 patients who were risk stratified into low, intermediate, and high risk. Intermediate risk represented the majority of patients in this group with 41 patients (48%), low risk and high risk represented 16 patients (19%) and 29 patients (33%), results respectively. 5 patients had missing data, so we did not classify them. Primary AML accounted for 70 (76%) of all patients, secondary AML accounted for 21 (23%) and the most common cause for secondary AML was MDS.
Table 1: Patients characteristics (N=91)


Click here to view


In our group, the treatment was either curative (intensive chemotherapy) or noncurative (palliative) for newly diagnosed AML patients based on clinical decision. Intensive chemotherapy was given to 74 (81%) and 17 (19%) of patients were treated with palliative treatment only. Majority of patients received induction with 3 + 7 chemotherapy regimen (57 patients). The remaining patients in intensive therapy group were given different regimens such as (5 + 2) regimen, or high-dose cytarabine or acute promyelocytic leukemia induction regimen. In the palliative treatment group, different treatment options were given including low dose subcutaneous cytarabine in 4 patients, azacitidine in 1 patient and the remaining patients received only oral chemotherapy or best supportive measures. Furthermore, 18 (24%) patients had been treated with allogeneic stem cell transplant (SCT) either in first remission or second or third remission on disease relapse.

As shown in [Table 2], the remission rate among all patients and in each risk group or FAB subtypes. The complete remission (CR) rate after induction therapy in intensive chemotherapy group (≥1 cycle) was 62 (84%) patients (out of 74 patients). The remaining 12 patients (16%) were refractory to the induction therapy. The CR rate after one induction cycle was 73%. Low-risk patients had the highest CR rate compared to intermediate-risk and high-risk patients. The CR was 14 (93%) of the low-risk patients, 27 (79%) of the intermediate risk patients and 20 (87%) of the high-risk patients. However, the difference was not statistically significant (P = 0.4). The remission rate according to FAB subgroups was the following; patients with AML M3 as expected have the highest rate of complete response (100%), patients with AML M0 and M7 had the lowest rate of response 0% and 67%, respectively. However, the number of patients in each of these two subgroups is very small.
Table 2: Remission rate in patients receiving intensive chemotherapy (N=74)


Click here to view


[Table 3] summarizes the relapse rate among all patients and in each risk group and FAB subtypes. There were 24 (41%) patients out of 59 patients, who had CR relapsed, 3 patients were not included due to incomplete data. The relapse rate according to different risk classes showed 5/12 (42%) low risk, 9/27 (33%) intermediate risk, and 10/19 (53%) high-risk patients had relapsed. Though the difference was not statistically significant (P = 0.4). [Table 3] shows the relapse rate in different FAB pathologic subtypes is as following: Nine out of 12 M1 patients, six out of 11 M2 patients, one out of 4 M3 patients, two out of 5 M4 patients, one out of 7 M5 patients, two out of 2 M7 patients had relapsed.
Table 3: Relapse rate among patients with previous remission (N=59)


Click here to view


[Table 4] summarizes the survival among the population, risk groups, and FAB subtypes. After a median follow-up of 19 months, the overall survival (OS) was 40 (46%), 4 patients had missing data regarding the survival. There were 37 (53%) patients out of 70 survived in the intensive therapy group, and 3 (19%) in the palliative therapy group survived. Most of the deaths happened in the first 6 months after diagnosis and after a follow-up of 34 weeks there were not any deaths among the population [Figure 1]. High-risk patients had the poorest OS, 10 (36%) patients out of 28, 8 (57%) low-risk patients out of 14, and 21 (52%) intermediate risk patients out of 40 survived [Figure 2]. But there was no statistical significant difference among the subgroups, (P = 0.4). There were 18 (24%) of patients received SCT, 8 (44%) of them had relapsed and 13 (72%) had survived with median follow-up of 17 months [Table 5] and [Figure 3].
Figure 1: Overall survival of the whole population

Click here to view
Figure 2: Overall survival of different risk groups

Click here to view
Figure 3: Survival rate of patients who underwent allogeneic stem cell treatment

Click here to view
Table 4: Overall survival (N=87)


Click here to view
Table 5: Outcome of patients who underwent stem cell transplant


Click here to view


The flow cytometric panel for AML includes these markers (CD2, CD3, CD4, CD5, CD7, CD10, CD11b, CD11c, CD13, CD14, CD15, CD19, CD20, CD22, CD33, CD34, CD45, CD56, CD61, CD64, CD71, CD41, CD61a, CD117, HLA-DR, MPO, TdT, and cytoplasmic CD3%) [Table 6] and [Table 7]. CD13, CD33, and CD117 were the most common positive markers at diagnosis of all AML subtypes. CD2, CD4, CD7 were the most common aberrant lymphoid antigens expressed among AML cases. 2 patients did not have any data regarding the immunophenotypes.
Table 6: Immunophenotypes (CD2-CD33)


Click here to view
Table 7: Immunophenotypes (CD34-cCd3%)


Click here to view



  Discussion Top


In this retrospective study, we were able to show some of the clinical and pathological features of AML in Saudi patients treated at a single center. In this small group of patients, discussion the classification according to the old FAB AML classification showed predominance of M1 and M2, followed by M4 and M5 with cases of M0, M6 and M7 representing only around 5%. Another local study, on AML patients showed that M4 and M5 are the dominant subtypes. [10] Regarding the risk stratification for our patients', the majority was in the intermediate risk group with most of those patients having normal cytogenetic. However, as has been shown recently in many studies those patients with normal cytogenetic can be further stratified into favorable or high risk based on presence or absence of certain molecular genetic aberrations. Patients with normal cytogenetic and with FLT3 mutation tend to have poor outcome and patients with mutated NPM or CEPBA in absence of FLT3 mutation tend to have a favorable outcome. [11] In our patients series, we were not able to sub-stratify patients with normal cytogenetic based on molecular aberrations because those tests were either not done, or the results are not available at the time of data collection.

The CR rate postinduction chemotherapy in our patient cohort was 73% after one induction cycle and 84% after one or more cycles. This high rate of CR in our patients population was seen in all risk groups. This response rate is higher than what has been reported from different clinical trials (60-70%). [11] Another local study on AML patients showed that 65% of the study population had first CR. [10] Possible explanations for the high response rate in our patients, we may have included some patients with favorable risk based on molecular genetic mutations, and usually those patients have high response rate. Another possible reason for this high complete response rate is inclusion of those who received multiple induction cycles, that is, more than one cycle and subsequently achieved a complete response. Furthermore, the OS rate was different than what is usually reported in other studies. The OS rate for low-risk group in our study is 57% and for high-risk group 36% this is in contrast to what has been reported of OS rate above 70% for low-risk AML and <20% for high-risk patients. [12],[13] The allogeneic SCT group has a better OS (72%), suggesting that this procedure may improve the outcome of AML patients especially the high-risk group. The low-risk group had high remission rate but lower than expected OS rate and a possible explanation for this is the lack of utilizing molecular mutations in our classification for risk groups. It has been reported that patients with certain favorable cytogenetic changes may have a poor outcome such as t (8;21) in the presence of c-KIT mutation, and allogeneic hematopoietic SCT may improve the outcome in such cases. [14]

Abnormal blasts usually start to show morphological maturation, usually express precursor markers, including CD34, CD117. Each FAB subtypes has its own characteristic immunophenotypes, M3 subtype in particular has its own unique immunophenotype which can be differentiated from other FAB subtypes of AML. In this study, M3 cases were always negative for CD22, CD34, CD15, and HLA-DR. Our study showed that CD13, CD33, CD117, and MPO were the most common positive presenting antigens among M3 patients which is similar to another study findings. [8] Another study showed that CD45, CD33, CD13 were the most commonly expressed antigens. [15] CD2, CD4, CD7 were the most common apparent lymphoid antigens co-expressed in our AML cases. In addition to a local study, which showed CD9, CD7, CD19, CD4, and CD22, [16],[17] our study showed CD2 was expressed in patients with M2 and M7 subtypes.

There were some limitations in our study including the retrospective nature of this study and a single center review. Furthermore, there were many patients included in the initial evaluation of treatment and response rate but had missing data. Finally, the molecular results of AML-related mutational analysis were not included in this group of patients for reasons mentioned previously.


  Conclusion Top


This study shows M1 subtype to be the most common of AML in this population. In addition, the CR was better with similar survival rate as compared to other local and internationally published experiences. These results, albeit with its limitations, need to be confirmed in a prospective clinical trial or on a disease-based registry at the national level.

 
  References Top

1.
Kumar CC. Genetic abnormalities and challenges in the treatment of acute myeloid leukemia. Genes Cancer 2011;2:95-107.  Back to cited text no. 1
    
2.
Gentles AJ, Plevritis SK, Majeti R, Alizadeh AA. Association of a leukemic stem cell gene expression signature with clinical outcomes in acute myeloid leukemia. JAMA 2010;304:2706-15.  Back to cited text no. 2
    
3.
Fernandez HF, Sun Z, Yao X, Litzow MR, Luger SM, Paietta EM, et al. Anthracycline dose intensification in acute myeloid leukemia. N Engl J Med 2009;361:1249-59.  Back to cited text no. 3
    
4.
Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, et al. WHO Classification of Tumors of Hematopoietic and Lymphoid Tissues. IARC WHO Classification of Tumours, No. 2. Vol. 2. IARC Press; Available from: http://www.apps.who.int/bookorders/anglais/detart1.jsp?codlan=1 and codcol=70 and codcch=4002. [Last accessed on 2014 Jul 28].  Back to cited text no. 4
    
5.
National Cancer Registry, MOH, KSA. Cancer Incidence Report. Saudi Arabia; 2009.  Back to cited text no. 5
    
6.
Bennett JM, Catovsky D, Daniel MT, Flandrin G, Galton DA, Gralnick HR, et al. Proposals for the classification of the acute leukaemias. French-American-British (FAB) co-operative group. Br J Haematol 1976;33:451-8.  Back to cited text no. 6
    
7.
Abdel-Wahab O. Molecular genetics of acute myeloid leukemia: Clinical implications and opportunities for integrating genomics into clinical practice. Hematology 2012;17 Suppl 1:S39-42.  Back to cited text no. 7
    
8.
Kawankar N, Korgaonkar S, Kerketta L, Madkaikar M, Jijina F, Ghosh K, et al. DNA copy number changes and immunophenotype pattern in karyotypically normal acute myeloid leukemia patients from an Indian population. Genet Test Mol Biomarkers 2012;16:265-70.  Back to cited text no. 8
    
9.
Jiang NG, Chen XM, Zhu HL, Zhong L, Zeng TT, Jia YQ. Immunophenotype characteristics and prognosis of acute leukemia patients with cross expressing lymphoid and myeloid lineage associated antigens. Zhongguo Shi Yan Xue Ye Xue Za Zhi 2010;18:1405-9.  Back to cited text no. 9
    
10.
Harakati MS, Al-Momen AM, Ajarim DS, Al-Moharib FI, Al-Theyab A, Fawzy EM, et al. Adult acute myeloblastic leukemia: Experience at King Khalid University Hospital. Ann Saudi Med 1998;18:221-5.  Back to cited text no. 10
    
11.
Gregory TK, Wald D, Chen Y, Vermaat JM, Xiong Y, Tse W. Molecular prognostic markers for adult acute myeloid leukemia with normal cytogenetics. J Hematol Oncol 2009;2:23.  Back to cited text no. 11
    
12.
American Cancer Society. Cancer Facts and Figures. Atlanta, Ga: American Cancer Society; 2013. Available from: http://www.cancer.org/acs/groups/content/@epidemiologysurveilance/documents/document/acspc-036845.pdf. [Last accessed on 2014 Jul 28].  Back to cited text no. 12
    
13.
Slovak ML, Kopecky KJ, Cassileth PA, Harrington DH, Theil KS, Mohamed A, et al. Karyotypic analysis predicts outcome of preremission and postremission therapy in adult acute myeloid leukemia: A Southwest Oncology Group/Eastern Cooperative Oncology Group Study. Blood 2000;96:4075-83.  Back to cited text no. 13
    
14.
Ahmed FS, Al-Qurashi N, Chaudhri M, Aljurf H, Alzahrani H, Alsharif F, et al.Allogeneic haematopoietic stem cell transplantation in AML t(8;21) in first complete remission gives superior relapse free survival over repetitive high-dose cytosine arabinoside in certain populations (Abstract). Bone Marrow Transplant 2009;43 Suppl 1:99.  Back to cited text no. 14
    
15.
Byrd JC, Mrózek K, Dodge RK, Carroll AJ, Edwards CG, Arthur DC, et al. Pretreatment cytogenetic abnormalities are predictive of induction success, cumulative incidence of relapse, and overall survival in adult patients with de novo acute myeloid leukemia: Results from Cancer and Leukemia Group B (CALGB 8461). Blood 2002;100:4325-36.  Back to cited text no. 15
    
16.
Khalidi HS, Medeiros LJ, Chang KL, Brynes RK, Slovak ML, Arber DA. The immunophenotype of adult acute myeloid leukemia: High frequency of lymphoid antigen expression and comparison of immunophenotype, French-American-British classification, and karyotypic abnormalities. Am J Clin Pathol 1998;109:211-20.  Back to cited text no. 16
    
17.
El-Sissy AH, El-Mashari MA, Bassuni WY, El-Swaayed AF. Aberrant lymphoid antigen expression in acute myeloid leukemia in Saudi Arabia. J Egypt Natl Canc Inst 2006;18:244-9.  Back to cited text no. 17
    


    Figures

  [Figure 1], [Figure 2], [Figure 3]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]


This article has been cited by
1 Synergistic Anti Leukemia Effect of a Novel Hsp90 and a Pan Cyclin Dependent Kinase Inhibitors
Ashraf N. Abdalla,Mohamed E. Abdallah,Akhmed Aslam,Ammar Bader,Antonio Vassallo,Nunziatina De Tommasi,Waleed H. Malki,Ahmed M. Gouda,Mohammed H. Mukhtar,Mahmoud Zaki El-Readi,Hamad M. Alkahtani,Alaa A.-M. Abdel-Aziz,Adel S. El-Azab
Molecules. 2020; 25(9): 2220
[Pubmed] | [DOI]
2 AML in Saudi Arabia: analysis according to ELN 2017 cytogenetic classification
Amal S. Alabdulwahab,Hussein G. Elsayed,Mohamed A. Sherisher,Ahmed Zeeneldin,Wafa M. Elbjeirami
Clinical Lymphoma Myeloma and Leukemia. 2019;
[Pubmed] | [DOI]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Methods
Results
Discussion
Conclusion
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed3006    
    Printed56    
    Emailed0    
    PDF Downloaded612    
    Comments [Add]    
    Cited by others 2    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]