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\begin{document}

\title{Estimation of iron overload with T2*MRI vs. serum ferritin in children
treated for hematological malignancies}



\author[1]{Vinay Munikoty}%
\author[2]{Kushaljit Sodhi}%
\author[3]{Anmol Bhatia}%
\author[1]{PRATEEK BHATIA}%
\author[3]{Savita Attri}%
\author[4]{ManojKumar Rohit}%
\author[5]{Amita Trehan}%
\author[3]{N Khandelwal}%
\author[6]{Deepak Bansal}%
\affil[1]{Post Graduate Institute of Medical Education and Research}%
\affil[2]{Post graduate Institute of Medical Education \& Research}%
\affil[3]{Postgraduate Institute of Medical Education and Research}%
\affil[4]{Post Graduate Institute of Medical Education and Research, Chandigarh, India}%
\affil[5]{postgraduate Institute of Medical Education \& Research }%
\affil[6]{Advanced Pediatric Center, Postgraduate Institute of Medical Education and Research}%


\vspace{-1em}



  
  \date{May 26, 2024}


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\selectlanguage{english}
\begin{abstract}
Background. Iron overload may contribute to complications in childhood
cancer survivors. Methodology. Patients treated for hematological
malignancy, [?]6 months from the end of therapy, who had received [?]5
red-cell transfusions were enrolled in the cross-sectional study.
Iron-overload was estimated by serum ferritin (SF) and T2*MRI. Results.
Forty-five survivors were enrolled among 431 treated for hematological
malignancies. The median age at diagnosis was 7-years. The median number
of red-cell units transfused was 8 (IQR 7, 10). The median duration from
the end of treatment was 15 months (IQR 8.75, 25). An elevated SF
(\textgreater{}1000 ng/ml), elevated liver iron concentration (LIC) and
myocardial iron concentration (MIC) were observed in 5 (11.1\%), 20
(45.4\%), and 2 (4.5\%) patients, respectively. All survivors with SF
\textgreater{}1000 ng/ml had elevated LIC. The LIC correlated with SF
(p\textless{}0.001). MIC lacked correlation with SF or LIC. The number
of red-cell units transfused and duration from last transfusion
correlated with SF (p=0.001, 0.002) and LIC (p=0.012, 0.005). SF
\textgreater{}500 ng/ml predicted elevated LIC with
sensitivity/specificity of 80\%/79\%. A cut-off of 8 units of red-cells
predicted elevated LIC with sensitivity/specificity of 95\%/49.8\%.
Conclusions. Iron overload in survivors of hematological malignancies
who had received [?]5 red-cell transfusions, estimated by SF, LIC, and MIC
was 11.1\%, 45.4\%, and 4.5\%. We suggest screening by SF for survivors
who have received \textgreater{}8 transfusions. If SF is 500-1000 ng/ml,
a T2*MRI is useful for estimating LIC. A T2*MRI can be avoided if SF
exceeds 1000 ng/ml, as LIC will be expected to be elevated.%
\end{abstract}%



\sloppy


\textbf{1 INTRODUCTION}

Management of hematological malignancies with chemotherapy is
accompanied by myelosuppression, often necessitating blood
transfusions.\textsuperscript{1} The burden of transfusion-related iron
overload in childhood cancer survivors is less well
researched.\textsuperscript{2} There is overlap in organ toxicity due to
iron overload and late effects of cancer chemotherapy which may
contribute to poor quality of life in survivors. There are no
established guidelines for monitoring iron overload in pediatric cancer
survivors. In addition, there is a lack of information on the utility of
T2* magnetic resonance imaging (T2*MRI) vs. serum ferritin to estimate
iron overload in cancer survivors.

Serum ferritin is not a reliable predictor of tissue iron stores and
organ dysfunction.\textsuperscript{3} The estimation of liver iron
concentration (LIC) by T2*MRI has a superior correlation with liver iron
assessed with liver biopsy.\textsuperscript{4,5} T2*MRI has emerged as a
superior tool for estimating tissue iron overload in patients with
hemoglobinopathies.

The objective of this study was two-fold, a) to measure the prevalence
of iron overload in children treated for hematological malignancies, and
b) define the indication(s) for requesting T2*MRI vis a vis serum
ferritin for estimating iron overload in cancer survivors.

\textbf{2 METHODS}

A single-center, cross-sectional, observational study was conducted over
15 months (January 2016 to March 2017). Patients treated for
hematological malignancy in the Pediatric Hematology-Oncology Unit,
Postgraduate Institute of Medical Education and Research, Chandigarh,
India, were screened. Children who were \textgreater{}6 months from
completion of therapy and had received [?]5 red cell units during
treatment or within 3 months before diagnosis were enrolled. Patients
with relapsed disease, second-malignancy, or those who had received a
hematopoietic stem cell transplant (HSCT) were excluded. Protocol
adapted from UKALL 2003 trial was followed for risk stratification and
treatment of patients with acute lymphoblastic leukemia
(ALL).\textsuperscript{8} Chemotherapy adopted from the AML15 trial was
used to treat acute myeloid leukemia (AML).\textsuperscript{9}

Serum ferritin and T2*MRI were performed for estimation of iron
overload. The myocardial iron concentration (MIC) and LIC were measured
by T2*MRI. C-reactive protein (CRP) was done as a surrogate marker of
inflammation. A serum ferritin value was considered for assessment of
iron status when the corresponding CRP level was within range. If CRP
was elevated (\textgreater{}10 mg/L), serum ferritin and CRP were
repeated 4 weeks later.

Iron overload was defined as serum ferritin exceeding 1000 ng/ml. LIC
was graded as normal (\textless{}2 mg/g), mild (2-7 mg/g), moderate
(7-15 mg/g) or severe (\textgreater{}15 mg/g) iron
overload.\textsuperscript{6} MIC was graded as normal (\textless{}1.16
mg/g), mild (1.16-1.65 mg/g), moderate (1.65-2.71 mg/g) or severe
(\textgreater{}2.71 mg/g) iron
overload.\textsuperscript{7}Echocardiography was performed in children
with cardiac iron overload (MIC \textgreater{}1.16 mg/g).

The study was approved by the ethics committee of the institution
(INT/IEC/2016/1138). Informed consent was obtained from the
participants/guardians.

\textbf{2.1 Statistical Analysis}

Chi-square and Fischer's exact test were utilized to compare categorical
variables. The inter-group comparison was performed with the student's
t-test for parametric and Mann--Whitney test for nonparametric data.
Spearman's correlation was used to analyze the correlation between serum
ferritin and LIC/MIC. Multiple linear regression was performed to
predict the influence of independent parameters on serum ferritin and
LIC. All tests were two-tailed, and a P-value \textless{}0.05 was
considered significant. Analysis was performed using Statistical Package
for Social Sciences (SPSS Inc., Chicago, IL, version 23.0 for Windows).

\textbf{3 RESULTS}

The screening was performed in 431 patients treated for hematological
malignancies. Forty-five patients who fulfilled the study criteria were
enrolled and are discussed henceforth. The characteristics of the 45
patients are listed in Table 1. The median duration from the end of
treatment was 15 months (IQR 8.75, 25). The median duration since the
last transfusion was 33 months (IQR: 23.5, 47.5). The patients treated
with more intensive chemotherapy (regimen B for ALL) had a greater (8.9
vs. 7.9 units) transfusion requirement as compared to those treated with
standard (regimen A for ALL) chemotherapy, though it lacked significance
(p=0.066).

\textbf{3.1 Iron overload}

Serum ferritin was available in all 45 patients. T2*MRI was performed in
all except one patient due to the need for sedation. The mean serum
ferritin was 581 ng/ml (range: 32-2115). Iron overload (serum ferritin
\textgreater{}1000 ng/ml) was observed in 5 (11.1\%) patients. CRP
levels were \textless{}10 ng/ml in all. The mean LIC was 2.7 mg/g
(range: 0.6-12.7). The LIC was elevated (\textgreater{}2 mg/g) in 20
(45.4\%) patients; 18 (41\%) had mild, and 2 (4.5\%) patients had a
moderate grade of hepatic iron overload. The mean MIC was 0.6 mg/g
(range: 0-1.6). Merely 2 (4.5\%) patients had an elevated MIC, both with
a mild elevation. The two patients with the cardiac iron overload
included a patient with high-risk ALL and another with AML. An
echocardiogram was performed in both patients with cardiac iron
overload. The ALL survivor had grade 2 diastolic dysfunction, and the
other had a normal function.

\textbf{3.2 Correlation of serum ferritin with LIC and MIC}

All patients with serum ferritin \textgreater{}1000 ng/ml had an
elevated LIC. LIC had a linear correlation with serum ferritin (r=0.49,
p\textless{}0.001) (Figure 1). MIC lacked correlation with serum
ferritin (r=0.20, p=0.19) as well as LIC (r=0.04, p=0.81).

\textbf{3.3 Variables influencing serum ferritin, LIC, and MIC}

The patients receiving \textgreater{}10 red cell transfusions had higher
mean serum ferritin (938 vs. 451 ng/ml, p=0.001) and a higher mean LIC
(4.0 vs. 2.2, p=0.035) as compared to the group receiving \textless{}10
transfusions. The number of red cell units transfused correlated with
serum ferritin and LIC. Children who were evaluated after 3 years from
cessation of transfusions had lower serum ferritin (mean: 350 vs. 751
ng/ml) as well as a lower LIC (mean: 1.2 vs. 3.8 ng/ml) than those who
were evaluated within 3 years from cessation of transfusions. The
duration since the last transfusion inversely correlated with serum
ferritin and LIC. The variables lacked a correlation with MIC (Table 2).

\textbf{3.4 Predictive value of serum ferritin and number of red cell
transfusions for abnormal LIC}

A serum ferritin exceeding 500 ng/ml had a sensitivity of 80\% and
specificity of 79\% to predict an elevated LIC. Serum ferritin exceeding
1000 ng/ml uniformly predicted elevated LIC in all the patients
(specificity: 100\%); however, the sensitivity dropped to 25\%. A
cut-off of 8 units of red cells predicted an elevated LIC with a
sensitivity of 95\% and specificity of 49.8\%.

\textbf{4 DISCUSSION}

Blood transfusions are a vital component in the management of
hematological malignancies. There is a cumulative increase in tissue
iron burden with repeated blood transfusions. As an effective mechanism
of excretion is lacking, the excess iron is sequestered as ferritin.
Even with mild to moderate iron overload, the transferrin saturation
exceeds 80\%. It results in the production of non-transferrin bound
iron. Subsequently, free cytosolic iron accumulates in the `labile iron
pool,' leading to lipid peroxidation, protein denaturation, and nucleic
acid damage, ultimately resulting in tissue
dysfunction.\textsuperscript{10,11}

It is well known that severe iron overload results in cardiopulmonary,
endocrine, liver, hematological, and other organ
dysfunction.\textsuperscript{12} Mild and moderate iron overload is not
without adverse effects.\textsuperscript{13} Iron overload hinders
erythropoiesis by causing mitochondrial iron trapping and decreasing
hemoglobin synthesis. It has been observed that the erythroid-specific
colony-forming units reduce even with a mild increase in ferritin
(\textgreater{}250 ng/ml).\textsuperscript{14} Iron overload also
results in immunological dysfunction. Iron induces oxidative damage in
the immune system resulting in impaired defence
mechanisms.\textsuperscript{15} Iron metabolism in malignancies is
altered. There is increased expression of transferrin binding proteins
and the formation of low molecular weight siderophores. There is a
decrease in the tumoricidal activity of lymphocytes and
macrophages.\textsuperscript{16} In addition, there is a substantial
overlap of organ toxicities between cancer chemotherapy and iron
overload. The risks of iron overload are exemplified further if there is
a need for HSCT at relapse. Pre-transplant iron overload is associated
with an increased risk of hepatic sinusoidal syndrome, graft versus host
disease, infection, and mortality.\textsuperscript{17} Hence mild to
moderate iron overload merits monitoring in follow of cancer survivors.

About 15-20\% of long-term survivors of adult leukemia develop iron
overload.\textsuperscript{18} The earlier studies on childhood cancer
survivors report a variable (14-28\%) range of iron overload. In a study
from Finland, 3/22 (14\%) children treated for ALL had iron overload
(ferritin \textgreater{}1000 ng/ml) with median serum ferritin of 450
ng/ml.\textsuperscript{19} Another study from Turkey reported iron
overload in 20/53 (38\%) children treated for ALL and
AML.\textsuperscript{20} In a study from India, 16/66 (24.2\%) children
treated for leukemia had iron overload (SF\textgreater{}1000
ng/ml).\textsuperscript{21} A study conducted at Children Hospital Los
Angeles evaluated 75 patients treated for pediatric cancers, both solid
tumors and hematological malignancies. Serum ferritin was elevated in
21/74 (28.4\%) at a median duration of 4.4 years after treatment
completion and 4.9 years from cessation of
transfusion.\textsuperscript{22} Prevalence of iron overload (ferritin
\textgreater{}1000 ng/ml) was reported in 7/27 (25.9\%) recipients of
allogeneic HSCT in a study conducted at the University of
Minnesota.\textsuperscript{23} In our study, iron overload (ferritin
\textgreater{} 1000 ng/ml) was observed in 5/45 (11.1\%) patients. The
plausible reasons for a lower burden of iron overload in our study are,
a) patients with relapsed disease or those receiving HSCT were excluded,
b) patients with high-risk ALL were treated with a less intensive
regimen B and not regimen C (as per UKALL 2003 protocol) in accordance
with the unit's policy, c) the threshold for transfusion was typically 8
g/dl as against 10 g/dl in a few earlier studies.

Several studies have attempted to correlate serum ferritin with LIC and
MIC.\textsuperscript{24-27} A study from St Jude Children's Research
Hospital reported elevated serum ferritin (median 1337 ng/ml) and LIC
(median 6.6 mg/g) in 8/63 (12.6\%) childhood cancer survivors. A
significant correlation was reported between serum ferritin and LIC
(r=0.83, p=0.01).\textsuperscript{23} Yet another study reported a
significant correlation between serum ferritin and MRI-based signal
intensity ratio of liver to the muscle (r=-0.76, p\textless{} 0.001,
n=15).\textsuperscript{25} In a study from California, 75 patients
treated for childhood cancers were evaluated by T2*MRI. The LIC and
pancreatic iron were elevated in 36/74 (49.3\%) and 19/72 (26.4\%)
patients. None of the patients had an abnormal MIC. Both LIC and
pancreatic iron stores correlated with serum ferritin (r=0.472,
p\textless{}0.001).\textsuperscript{22} Serum ferritin and T2*MRI-based
iron estimation were performed in 48 adult recipients of HSCT who had
received a median of 20 red cell transfusions. Iron overload (ferritin
\textgreater{}1000 ng/ml) and liver iron overload (\textgreater{}5 mg/g)
was reported in 33/48 (6\%) and 41/45 (85\%) patients, respectively.
Serum ferritin and LIC had a significant correlation (r=0.75). Cardiac
iron overload was reported in merely one patient, and there was no
correlation with ferritin.\textsuperscript{28} A study from Belgium
evaluated 59 patients with pediatric cancers. The mean serum ferritin
was 465 ng/ml. An elevated LIC and MIC were observed in 39/59 (69\%) and
8/59 (14\%) patients, respectively. Serum ferritin correlated with LIC
(r=0.74), but not with MIC (r=-0.27).\textsuperscript{29} In our study,
similarly, serum ferritin correlated with LIC (r=0.49, p=
\textless{}0.001) but not with MIC (r=0.20, p=0.19). In addition, the
MIC did not correlate with LIC (r=0.04, p=0.81). Serum ferritin can thus
be utilized as a surrogate indicator of liver iron overload. However,
MIC cannot be predicted based on serum ferritin or LIC.

The proportion of patients with iron overload differs when assessment is
performed by serum ferritin or . Armand et al., reported 33 (69\%)
patients with serum ferritin \textgreater{}1000 ng/ml and 41 (85\%) with
an abnormal (\textgreater{}1.8 mg/g) in 48 evaluated
patients.\textsuperscript{28} Kathleen et al., reported serum ferritin
\textgreater{}1000 ng/ml in 21/74 (29\%) and an elevated in 36/74 (49\%)
patients.\textsuperscript{22} A recent study reported 27.3\% patients
with abnormal and 18.2\% with abnormal MIC in patients with a serum
ferritin below 1000 ng/ml.\textsuperscript{26} In our study, the
proportion of patients with an increased was 45.4\%, considerably more
than the proportion of patients with a raised ferritin (11.1\%). All
patients with a serum ferritin exceeding 1000 ng/ml had an increased
(\textgreater{}2 mg/g). However, 6 (22.2\%) patients with a serum
ferritin below 1000 ng/ml had an abnormal as well. The MIC was abnormal
in 2 patients; both had serum ferritin below 1000 ng/ml. Thus, although
serum ferritin correlates well with , a cut-off \textgreater{}1000 ng/ml
underestimates the proportion of patients with tissue iron overload.

The predictive factors that influence iron stores help establish risk
factors for iron overload. In a prospective study of 59 patients, higher
treatment intensity was the sole parameter predicting liver iron
overload in multivariate analysis of risk factors (OR=19.54,
\selectlanguage{greek}β\selectlanguage{english}=2.97).\textsuperscript{29} Similarly, another study from Lithuania
evaluated 66 patients based on the intensity of treatment received.
Serum ferritin was higher in the higher-intensity group (mean 1071 ng/ml
vs. 402 ng/ml, p=0.008).\textsuperscript{30} A recent study in children
treated for acute leukemia (n=53) reported a higher treatment intensity
to result in higher ferritin (mean 406 vs. 260 ng/ml,
p\textless{}0.001).\textsuperscript{20} In the above two listed studies,
authors opined that the higher transfusion requirement in the group
treated with the higher intensity treatment likely explained the
increased iron load.\textsuperscript{29,30} In our study as well, the
patients treated with more intensive chemotherapy (regimen B for ALL)
had a higher (8.9 vs. 7.9 units) transfusion requirement as compared to
standard (regimen A for ALL) chemotherapy. However, the difference was
not significant (p=0.066). In our study, the intensity of therapy was
not a risk factor for higher serum ferritin or an elevated LIC (p=0.6,
0.73, respectively). The institutional policy of not utilizing regimen C
for treating patients with ALL likely contributed to a lack of
correlation of treatment intensity with iron overload.

Childhood cancer survivors receiving multiple transfusions are expected
to have greater serum ferritin than non-transfused
patients.\textsuperscript{31} A study from Turkey evaluated 22 children
treated for ALL with T2*MRI. LIC and MIC were elevated in 11 (50\%) and
6 (27\%) patients. None of the patients receiving less than 10
transfusions had liver or cardiac iron overload. Abnormal LIC (27.3\%)
and MIC (18.3\%) were observed in patients receiving more than 10
transfusions, although the SF was \textless{}1000 ng/ml. The number of
blood transfusions was a more reliable parameter than serum ferritin
(p=0.021 vs. 0.324) in predicting cardiac iron
overload.\textsuperscript{26} In another study from Turkey, 7 (23.3\%)
had mild and 1 (3.3\%) had moderate liver iron deposition among 30
children treated for ALL. LIC correlated with the serum ferritin, the
number of red cell units transfused, and the volume of red cell
transfused.\textsuperscript{32} In a study of 36 patients from New
Jersey, iron overload and serum ferritin were significantly elevated in
the group receiving \textgreater{}10 transfusions (mean ferritin: 3939
vs. 372 ng/ml, p= 0.05) as compared to the group receiving \textless{}10
transfusions. All patients with iron overload (ferritin
\textgreater{}1500 ng/ml) had received \textgreater{}10
transfusions.\textsuperscript{33} Two other similar studies reported a
correlation between liver iron overload and the volume of blood
transfused (r=0.67, 0.78).\textsuperscript{25,29} Two recent studies
have suggested serum ferritin and transfusion history as the best
parameters for predicting an elevated LIC.\textsuperscript{19,28} Number
of blood transfusions was a significant predictor for iron overload in
our study as well. A positive correlation was observed with both serum
ferritin (r=0.6, p=0.001) and LIC (r=0.375, p=0.012). In our study,
patients receiving \textgreater{}10 red cell transfusions had higher
mean serum ferritin (938 vs. 451 ng/ml, p=0.001) and a higher mean LIC
(4.0 vs. 2.2, p=0.035) as compared to the group receiving \textless{}10
transfusions. Indeed, a restrictive transfusion strategy would minimize
the burden of iron overload.

In childhood cancer therapy, the need for red cell transfusions is often
limited. The iron loading halts following the cessation of transfusions.
However, there is no mechanism of excretion of the residual iron load.
The cumulative iron stores may persist in the human system for a long
duration and result in organ dysfunction. Halonen et al. evaluated serum
iron parameters in children treated for ALL at the end of treatment
(n=30) and again 1-3 years (n=22) after completion of therapy. All iron
parameters improved, and iron profile normalized in
most.\textsuperscript{19} Similarly, serial measurements of serum
ferritin demonstrated a reduction from 28\% (8/28) to 14\% (4/28) at 1
and 2 years of follow-up in 66 children evaluated for
transfusion-related iron overload.\textsuperscript{30} In our study,
children were evaluated at a median duration of 33 months from the last
transfusion. Our study was cross-sectional, and iron parameters were not
serially evaluated. However, serum ferritin and LIC levels negatively
correlated with `duration since the last transfusion' (r=-0.45, -0.41,
respectively). Children who were evaluated after 3 years from cessation
of transfusions had lower serum ferritin (mean: 350 vs. 751 ng/ml) as
well as a lower LIC (mean: 1.2 vs. 3.8 ng/ml) than those who were
evaluated within 3 years from cessation of transfusions. It indicates
that iron overload tends to reduce with time.

There are no established guidelines for the treatment of iron overload
in cancer survivors. The need for chelation has not been systematically
studied. Several groups have initiated chelation at a ferritin level
exceeding 1000 ng/ml. Few studies report a decrease in iron overload
with iron chelation for a brief period.\textsuperscript{20,34,35} A
short-term chelation therapy may thus halt the adverse effects that
would ensue in mild to moderate iron overload for several years. We were
not inclined to administer iron chelation to our patients with iron
overload. The factors influencing the decision included a) likelihood of
drop-in body iron stores in growing children and with menstruation in
females, b) predominant vegetarian diet in the community, and c) a lack
of robust evidence of harm with mild iron overload.

Earlier studies have reported an incidence of 14-18\% cardiac
dysfunction in long-term survivors of childhood
cancers.\textsuperscript{36,37} In a study by Cheung et al. (n=58),
adult survivors of pediatric leukemia were evaluated for evidence of
myocardial iron overload on MRI. None of the patients had an abnormal
MIC. Subnormal left ventricular ejection fraction (\textless{}55\%) was
documented in 5/58 (9\%).\textsuperscript{38} Lutz et al. reported three
pediatric leukemia cases with high cumulative red cell transfusions
(45-114 units). MIC was mildly elevated in two. None of the patients had
cardiac function abnormality as evaluated by
Echocardiography.\textsuperscript{39} In our study, of the two patients
who had elevated MIC, one patient had diastolic dysfunction.

Our study has addressed a focused aspect of survivorship.The study
population was homogenous. Patients with hematologicmalignancies
treated with chemotherapy and in complete remission were enrolled. It is
one of the largest studies to perform MRI-based tissue iron estimation
in children treated for childhood cancer. The results aided in
calculating the cut-off value of serum ferritin and the number of red
cell transfusions received to predict an abnormal LIC. It would help
formulate chelation therapy guidelines in cancer survivors with iron
overload.

The study has limitations. The volume of blood transfused (ml/kg) was
not recorded. Hence the critical volume of blood and transfused iron at
which iron overload ensues was not estimated. The study was a
cross-sectional, observational study. Serial measurements of ferritin
and T2*MRI were not done. It would have provided additional information
on ironutilization during the follow-up. In addition, the study was not
intended to answer the question of indication or requirement for iron
chelation in children treated for cancers.

In conclusion, the occurrence of elevated LIC and MIC in children
treated for hematological malignancies who had received \textgreater{}5
red cell transfusions were 45.4\% and 4.4\%, respectively. No patient
had a severe degree of elevation of LIC or MIC. Screening for iron
overload by serum ferritin is suggested for patients who have received
more than 8 transfusions. If the serum ferritin is between 500-1000
ng/ml, a T2*MRI may be considered for estimating liver iron overload.
The LIC was uniformly elevated in patients with serum ferritin exceeding
1000 ng/ml. Therefore, a T2*MRI may be avoided in patients with serum
ferritin \textgreater{}1000 ng/ml for optimal resource utilization. A
prospective study with serial evaluation of iron load will aid in
understanding the dynamics of iron overload with time. The indications
and necessity for treating mild or moderate iron overload in children
treated for cancer needs to be ascertained.

\textbf{CONFLICT OF INTEREST}

The authors declare that there is no conflict of interest.

\textbf{DATA AVAILABILITY STATEMENT}

The data that support the findings of this study are available from the
corresponding author upon reasonable request.

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\end{enumerate}

\textbf{LEGENDS}

\textbf{FIGURE 1} Scatter plot depicting the correlation between liver
iron concentration and serum ferritin. The parameters had a linear
correlation (r=0.49). As the serum ferritin increased, the LIC increased
as well (p\textless{}0.001).

\textbf{Hosted file}

\verb`TABLE 1.docx`  available at \url{https://authorea.com/users/741197/articles/713606-estimation-of-iron-overload-with-t2-mri-vs-serum-ferritin-in-children-treated-for-hematological-malignancies}

\textbf{Hosted file}

\verb`TABLE 2.docx`  available at \url{https://authorea.com/users/741197/articles/713606-estimation-of-iron-overload-with-t2-mri-vs-serum-ferritin-in-children-treated-for-hematological-malignancies}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/FIGURE-1/FIGURE-1}

\end{center}
\end{figure}

\selectlanguage{english}
\FloatBarrier
\end{document}

