CLINICAL & BASIC RESEARCH

SQU Med J, May 2011, Vol. 11, Iss. 2, pp. 215-220, Epub. 15th May 11
Submitted 12th Jul 10
Revision ReQ. 28th Sept 10, Revision recd. 9th Nov 10
Accepted 15th Dec 10

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2009 2004

 21 181
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 5P 0.81


 5



:مفتاح الكلمات

aBstract: Objectives: This study aimed to assess the incidence and trend of childhood leukaemia in Basrah. 
Methods: This was a hospital-based cancer registry study carried out at the Pediatric Oncology Ward, Maternity & 
Children’s Hospital and other institutes in Basrah, Iraq. All children with leukaemia, aged 0 to 14 years diagnosed 
and registered in Basrah from January 2004 to December 2009 were included in the study. Their records were 
retrieved and studied. The pattern of childhood leukaemia by year of diagnosis, age at diagnosis, morphological 
subtypes, and geographical distribution was analysed. Rates of childhood leukaemia over time were calculated for 
six years using standard linear regression. Results: The total number of cases of childhood leukaemia was 181. The 
number of cases ranged from 21 in year 1, to 31 in the final year reaching a peak of 39 in 2006. Leukaemia rates did 
not change over the study period (test for trend was not significant, P = 0.81). The trend line shows a shift towards 
younger children (less than 5 years). The commonest types of leukaemia were acute lymphoblastic leukaemia (ALL), 
then acute myeloid leukaemia (AML) and finally chronic myeloid leukaemia (CML). Conclusion: Annual rates of 
childhood leukaemia in Basrah were similar to those in other countries with a trend towards younger children. 
This raises the question about the effect of environmental catastrophes in the alteration of some specific rates of 
childhood leukaemia, rather than the overall incidence rate. There is a need for further epidemiological studies to 
understand the aetiology of childhood leukaemia in Basrah. 

Keywords: Childhood leukemia; Incidence; Time trend; Cancer registry study; Basrah; Iraq

CLINICAL & BASIC RESEARCH

Time Trends and Geographical Distribution 
of Childhood Leukaemia in Basrah, Iraq,

from 2004 to 2009 
*Laith A Alrudainy,1 Jenan G Hassan,2 Hussam M Salih,2 Mohammed K Abbas,2 Athar AS Majeed2

CLINICAL & BASIC RESEARCH

1Department of Community Medicine, College of Medicine, University of Basrah, Iraq; 2Basrah Maternity and Children Hospital, 
Basrah, Iraq.
*Corresponding Author email: Alrudainy_laith@yahoo.com

Advances in Knowledge 
1. This article is based on one of many studies by the Basrah Cancer Research Group and looks at the time trends and geographical 

distribution of childhood leukaemia in Basrah.



Laith A Alrudainy,Jenan G Hassan,Hussam M Salih, Mohammed K Abbas and Athar AS Majeed

Clinical and Basic Research | 215

Leukaemia is the most common childhood cancer, accounting for 25% to 35% of the incidence of all childhood cancer 
among most populations.1,2 

The commonest type of childhood leukaemia is 
acute lymphoblastic leukaemia (ALL), which occurs 
in approximately 80% of leukaemia cases, followed 
by acute myeloid leukaemia (AML) and chronic 
myeloid leukaemia (CML), and a few in other 
categories.3

The incidence of childhood leukaemia is higher 
in resource rich countries, ranging from 4.0 to 4.4 
per 100,000 per year,4 and lower in less-income 
countries5 although these variations may reflect  
a lack of registrations of cancer in low-income 
countries.6 Studies from different parts of the 
world have indicated an increase in recent decades 
in the incidence of childhood leukaemia in some 
countries,7,8 while rates have stayed largely stable in 
the USA  and Nordic countries.9,10 In most countries, 
the incidence of childhood leukaemia is higher 
among boys than girls.11,12 Although the aetiology 
of most childhood leukaemias is unknown,13 several 
factors have been associated with the disease, 
including socioeconomic status,14,15 environmental 
exposures including ionising radiation and 
benzene,16 infectious agents,17 and parental 
exposure risk factors.18,19

Basrah is Iraq’s second largest city and its main 
port. It is located along the Shatt Al-Arab waterway, 
approximately 545 km southeast of Baghdad and 
adjacent to Iran and Kuwait. Basrah is composed 
of a flat alluvial plain formed by the combined 
flood plains and deltas of the Tigris, Euphrates, 
and Shatt Al-Arab rivers. The area surrounding 
Basrah has substantial petroleum resources with 
many oil wells. Basrah has been exposed to massive 

environmental pollution as a consequence of 
military conflicts and lack of an efficient protective 
policy from 1980 to 2003. Previous research work 
and growing impressions among physicians and 
lay people suggest that childhood leukaemia has 
increased in Basrah since the second Gulf war.20,21,22

However, these suggestions were criticised for 
being inadequate proof of a real increase in the 
risk of childhood leukaemia because of incomplete 
case registration and/or inaccurate population 
denominators before 2003. In order to study the 
subject properly, the Basrah Cancer Research Group 
(BCRG) was established in 2004. BCRG initiated a 
project to improve registration, identify risk factors, 
and improve care. This group has achieved good 
results in registration of cancer, including childhood 
leukaemia.23 

The purpose of this study was to assess the rates 
and trends of childhood leukaemia in Basrah, Iraq, 
from 2004 to 2009. The data reported here can be 
used for comparison with past figures or future 
findings.

Methods 
The Basrah governorate is divided into five areas 
congruent to the health sectors established by 
the Basrah health authorities: City centre, South 
Basrah, West Basrah North Basrah and East Basrah 
(see map, Figure 4). Information related to the 
population of Basrah was based on data available 
from Basrah Health Authorities, electronic lists 
and the Statistical Office in Basrah. The authors 
depended on the information from ration cards 
to assess the size of the population in Basrah. The 
ration card system was established from the 1990s 
to provide basic foodstuffs to Iraqi people during 

2. Although the rates of leukaemia in children aged 0 to 14 years did not change over the 6 year period (possibly because of incomplete cancer 
registration), the rates were much higher than in other Western and Eastern countries. This may be due to exposure to environmental 
leukemogens.

3. Another finding is the shift of the incidence of leukaemia in recent years towards children under 5 years. 
4. The highest average rate of childhood leukaemia is in West and East Basrah, two regions exposed to great environmental pollution 

during recent decades.

Application to Patient Care
1. The results of our study are useful for determining the extent of childhood leukaemia in Basrah in recent years. 
2. Comparison of the incidence rates in population groups that differ in exposures permits one to estimate the effect of exposure to a 

hypothesised factor of interest. 
3. The extent of the time trend and geographical distribution of childhood leukaemia will help in future planning of health care services, 

drug supplies, and other preventive measures for patients and the general population.



Time Trends and Geographical Distribution of Childhood Leukaemia in Basrah from 2004 to 2009 

216 | SQU Medical Journal, May 2011, Volume 11, Issue 2

the economic sanctions after the 1991 Gulf War. 
It is therefore the best way to assess the Basrah 
population's size under the prevailing circumstances, 
because the Iraqi government monitors it carefully 
for economic reasons. It is renewed annually to 
take into account migration, death, and births in 
the population. In comparison with other parts of 
Iraq, the population in Basrah is more stable and, 
due to a stable political and economic environment 
migration is not an important issue.

This hospital-based cancer registry study was 
based on all new cases of childhood leukaemia 
which were registered at the Pediatric Oncology 
Ward of the Basrah Maternity & Children’s Hospital 
and other institutes, e.g. the main oncology centre 
in Basrah, the cancer regisration section at the 
Department of Pathology, College of Medicine 
University of Basrah, and data from some specialist 
doctors who keep their own collection of cancer 
cases as part of their routine clinical work. The 
research protocol was approved by the Scientific 
Committee in the Department of Community 
Medicine, College of Medicine, University of 
Basrah, in December 2009. The permission of the 
Directorate of Health in Basrah was obtained prior 
to the research implementation. 

In Basrah, all childhood leukaemia cases 
are referred to the Pediatric Oncology Ward in 
Basrah’s Maternity & Children’s Hospital, which is 
responsible for the treatment and registration of all 
childhood malignancies in Southern Iraq. Many of 
the children are treated outside Iraq, but they are 

diagnosed and registered in Basrah before travelling. 
Diagnosis was based on the histopathology of the 
bone marrow and complete blood counts. Two 
haematologists agreed on all diagnoses, and no 
changes in diagnostic techniques occurred over 
the study period. Standard criteria are used to 
diagnose leukaemia, which for the purpose of this 
analysis have been divided into acute lymphoblastic 
leukaemia (ALL), acute myeloblastic leukaemia 
(AML), chronic myeloid leukaemia (CML), and 
chronic lymphocytic leukaemia. Cases identified 
by various sources were entered first on Excel 
spreadsheets in most centres, or identified from 
their original documents and entered by BCRG on 
Excel. Then, all the Excel files were merged, matched 
and checked for any duplications.

All analyses were carried out with the 
Statistical Package for the Social Sciences (SPSS) 
programme (Version 15.0). Some of the figures 
were constructed using Excel 2007. Incidence 
data were reported for each year by dividing the 
incidence by the population (aged 0–14 years) for 
each year, then multiplying by 100,000. To assess 
whether the increase in leukaemia rates over time 
was statistically significant, we calculated rates for 
the six years 2004–2009 and used standard linear 
regression to test whether the slope of the line 
between each year average rates was different from 
0. This method is similar to that used by Linet et al. 
in their study of the changes in leukaemia rates in 
the USA.24 Age standardised incidence was derived 
using the world standard population by the direct 
method.25

Results
There were 181 cases of leukaemia in children aged 
0–14 years registered in Basrah during the six years 
2004 to 2009. This represented 46.2 % of the total 
percentage of cancers among children in Basrah. 
The number of cases ranged from 21 cases in the 
first year to 31 cases in the final year and reached a 
peak of 39 cases in 2006 [Table 1].

Leukaemia rates in children aged 0 to 14 years 
did not change over the 6 year period (ratio of 
2008–2009 rate to 2004–2005 rate = 0.96; 95% 
confidence interval = 0.96 – 1.01). By using the 
parameter estimate from the regression model of 
untransformed values, it was found that leukaemia 
rates decreased by 0.123 per 100,000 during the 6 

Table 1: Leukaemia rates for children aged 0 to 14 years in 
Basrah, Iraq, from 2004 to 2009.

Year No. of 
leukaemia 

casesa

Populationb Rate per 
100,000 

population

2004 21 777,709 2.70

2005 32 837,293 3.82

2006 39 866,896 4.49

2007 27 946,377 2.85

2008 31 971,929 3.18

2009 31 998,171 3.10

Note: The data were collected from the cancer registry at the Pediatric 
Oncology Ward in Basrah Maternity & Children’s Hospital.
Legend:
a = cases of acute lymphoblastic leukaemia, acute myeloid leukaemia, 
and chronic myeloid leukaemia.
b = population aged from 0 to 14 years.



Laith A Alrudainy,Jenan G Hassan,Hussam M Salih, Mohammed K Abbas and Athar AS Majeed

Clinical and Basic Research | 217

year period: beta (B) = - 0.123; standard error (SE) 
= 0.17); the test for trend was not significant, with P 
= 0.81. We were satisfied that presentation of rates 
in Figure 1 was a robust finding of no change in 
childhood leukaemia in Basrah over the period of 
our study.

The total reported cases during the years 2004–
2009 shows that leukaemia was more frequent in 
boys (59.8%) than in girls (40.2%), with a male to 
female ratio of 149:100. The total leukaemia rate 
among boys was 3.63 per 100,000 during the years 
2004–2005 and 4.18 per 100,000 for 2008–2009. For 
girls, the rates were 3.03 during the earlier period 
and 2.07 during the most recent two year period 
(data not shown).

The trend line in Figure 2 shows the shift of 
the incidence of leukaemia in recent years towards 
younger children (below 5 years of age). In the 
2004–2005 period, children ages 0 through 4 had 
overall annual leukaemia rates of 3.04 per 100,000, 
compared with 3.46 for children aged 10 to 14 years. 
In the 2008–2009 period, children aged 0 to 4 years 
had an annual rate of 4.36 per 100,000, compared 
with 1.73 for children aged 10 to 14 years.

Different trends in incidence were observed for 
ALL, AML, and CML from 2004 to 2009 [Figure 
3]. In the period 2004–2005, there were 40 cases 
of ALL, 8 cases of AML, and 6 cases of CML. 
These case number reflect rates of 2.47 per 100,000 
children for ALL, 0.49 for AML, 0.37 for CML. 
During the period 2008–2009, the case counts and 
rates were 50 for ALL, 9 for AML, and 3 for CML, 
reflecting rates of 2.53, 0.45, and 0.15 per 100,000, 
respectively (data not shown). 

The rates of childhood leukaemia in each 

region of Basrah over the five years are shown 
in Figure 4. The highest rate was found in West 
Basrah (4.01/100,000), followed by East Basrah 
(3.88/100,000), North Basrah (3.69/100,000), South 
Basrah (3.58/100,000), and  Basrah city centre 
(2.77/100,000) respectively.

Discussion
The aim of this study was to describe rates and 
changes in childhood leukaemia for the population 
of Basrah, Iraq, in recent years. Data for this 
study were taken from the cancer registry of 
the Pediatric Oncology Word of the Maternal & 
Children’s Hospital in cooperation with the College 
of Medicine of the University of Basrah and the  
BCRG. 

Basrah is confronted with a range of 
environmental problems, some of which can be 
directly linked with the effects of recent military 
conflicts. Others have been triggered by internal 
Iraqi policies and actions, and were exacerbated by 
factors such as the impact of economic sanctions.26

During the 2003 Gulf war, there were reports 
of oil wells having been deliberately set on fire in 
the Rumeila oilfield in Basrah, while a thick haze 
of dark smoke could be seen from Kuwait City the 
following day. The broad categories of contaminants 
are volatile hydrocarbons, hydrogen sulphide, 
and naturally occurring radioactivity. Since the 
aromatic hydrocarbons (like benzene), which are 
known to be leukaemogenic, are the most volatile 
of hydrocarbons, exposure even at low levels can be 
very harmful.27 

Also, in Gulf wars of 1991 and 2003, the US 

Figure 1: Leukaemia rates and 95% confidence intervals 
among children aged 0 to 14 in Basrah, Iraq, from 2004 
to 2009

0

1

2

3

4

5

2004-2005 2008-20092006-2007

Year of diganosis

0-4 yrs

10-14 yrs

R
a
te

 
p
e
r
 
1
0
0
0
0
0

Figure 2: The rates of childhood leukaemia in Basrah, 
Iraq, according to the age and year of diagnosis.



Time Trends and Geographical Distribution of Childhood Leukaemia in Basrah from 2004 to 2009 

218 | SQU Medical Journal, May 2011, Volume 11, Issue 2

and UK Governments acknowledged that known 
depleted uranium munitions were used in Iraq. 
Many tons of this radioactive substance was 
targeted at the Basrah governorate.28

Our data show that the rates of leukaemia in 
children aged 0 to 14 years did not change over 
the 6 year period. This finding is inconsistent with 
Hagopian et al. study which reported that the 
average annual incidence of childhood leukaemia 
in Basrah has raisen substantially.22 In the Hagopian 
et al. study, the average annual rates of childhood 
leukaemia were measured by dividing the incidence 
by the population (aged 0–14 years) for each 
year, then multiplying by 100,000. The incidence 
included all new cases of childhood leukaemia that 
were diagnosed and treated in Basrah (included 
cases from Basrah and those who came from 
other provinces in southern Iraq) and divided by 
the estimated size of the population from Basrah 
province only; this led to an increase in the average 
annual rate to about 12 per 100,000. Also, the change 
in the trend of childhood leukaemia in Hagopian et 
al. study might be attributed to the underestimation 
of cancer cases, because of incomplete cancer 
registration prior to 2003 in Basrah.23

In the present study, leukaemias make up 
about 46% of paediatric cancers in Basrah, 
whereas international percentages ranged from 
27% of paediatric cancers in the United States, 
30% in Ireland and France, 33% in Germany, 
35% in Shanghai, China, and India.29–34 The high 
percentage of leukaemia in the present study 
may reflect the underestimation of other types of 
paediatric cancer, or it may be suggest a relatively 
higher risk of leukaemias in Basrah reflecting an 
exposure to certain risk factors, like the exposure  
to environmental leukemogens.

Another finding in the present study is the 
shift of the incidence of leukaemia in recent years 
towards younger children (below 5 years of age). 
Our results are similar to those from the United 
States and Great Britain,35 where the peak occurs 
between the age of 2–5 years, but the peak is 
less marked in less developed countries.36,37 This 
observation may also be attributed to the effect of 
environmental pollution and/or the changes in the 
life style of the population in Basrah in recent years 
compared to the West.  

The highest average rate of childhood leukaemia 
is present in West and East Basrah. These two 
regions were exposed to great environmental 
pollution during recent decades. West Basrah was 
exposed to many environmental carcinogens in the 
wars of 1991 and 2003 such as depleted uranium 
and aromatic hydrocarbons.  East Basrah was also 
affected by environmental pollution as a result of 
the military conflict in the period from 1980 to 
1988, during the Iraq-Iran War.  

On the other hand, our data show that the average 
annual rate of all types of childhood leukaemia (per 
100,000 children aged 0 – 14) did not noticeably rise 
in Basrah during the six years under review. Also, 
the rates of childhood leukaemia subtypes (ALL, 
AML, and CML) were not elevated. Because ALL 
was by far the commonest type, the trends in the 
rates of all leukaemias combined should mostly 
reflect trends in the incidence of ALL. 

Figure 3: The rates of acute lymphoblastic leukaemia 
(ALL), acute myeloid leukaemia (AML), and chronic 
myeloid leukaemia (CML) from 2004 to 2009

Figure 4: Average rates per 100,000 of childhood 
leukaemia in different areas of Basrah, 2004 – 2009: 1) 
Basrah City centre, 2) South Basrah, 3) West Basrah, 4) 
North Basrah, 5) East Basrah.



Laith A Alrudainy,Jenan G Hassan,Hussam M Salih, Mohammed K Abbas and Athar AS Majeed

Clinical and Basic Research | 219

Conclusion
Although we observed no temporal increase in the 
incidence rates for childhood leukaemia during the 
6 year period from 2004 to 2009, there is shift in 
the incidence of leukaemia in recent years towards 
younger children and there is an increase in the 
percentage of childhood leukaemia in comparison 
with other studies worldwide. This result raises 
the question about the effect of environmental 
pollution on the specific characteristics of childhood 
leukaemia rather than on the overall incidence rate.

It is known that the Basrah region was 
exposed to environmental insults including the 
known leukemogen benzene 27 and pyrophoric 
depleted uranium, 21,28   but also, and still ongoing, 
undifferentiated water and air pollution; however, 
no data are available on the doses to which the 
leukaemia patients in our study were exposed. 
There is a need for further epidemiological studies 
to understand the effect of environmental pollution 
on the pattern of childhood leukaemia in Basrah. 

c o n f l i c t o f i n t e r e s t
The authors reported no conflict of interest.

a c k n o w l e d g m e n t s

The authors would like to thank Professor Hans 
Peer Wagner, Professor of Paediatric Haematology 
and Oncology (University of Bern, Switzerland) 
for valuable discussions and for checking the 
manuscript. We express our appreciation to all the 
members of BCRG for their continuous effort in 
updating and improving the data collected. 

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