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World J Exp Med 2022 May 20; 12(3): 36-52
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Contents Bimonthly Volume 12 Number 3 May 20, 2022
MINIREVIEWS
Concise review of radiosurgery for contemporary management of pilocytic astrocytomas in children and
adults
36
Sager O, Dincoglan F, Demiral S, Uysal B, Gamsiz H, Gumustepe E, Ozcan F, Colak O, Gursoy AT, Dursun CU, Tugcu
AO, Dogru GD, Arslan R, Elcim Y, Gundem E, Dirican B, Beyzadeoglu M
Use of hydroxychloroquine and azithromycin combination to treat the COVID-19 infection
44
Bajpai J, Pradhan A, Verma AK, Kant S
WJEM https://www.wjgnet.com II May 20, 2022 Volume 12 Issue 3
World Journal of Experimental Medicine
Contents Bimonthly Volume 12 Number 3 May 20, 2022
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DOI: 10.5493/wjem.v12.i3.36 ISSN 2220-315x (online)
MINIREVIEWS
Concise review of radiosurgery for contemporary management of
pilocytic astrocytomas in children and adults
Omer Sager, Ferrat Dincoglan, Selcuk Demiral, Bora Uysal, Hakan Gamsiz, Esra Gumustepe, Fatih Ozcan,
Onurhan Colak, Ahmet Tarik Gursoy, Cemal Ugur Dursun, Ahmet Oguz Tugcu, Galip Dogukan Dogru,
Rukiyye Arslan, Yelda Elcim, Esin Gundem, Bahar Dirican, Murat Beyzadeoglu
Specialty type: Oncology
Provenance and peer review:
Invited article; Externally peer
reviewed.
Peer-review model: Single blind
Peer-review report’s scientific
quality classification
Grade A (Excellent): 0
Grade B (Very good): 0
Grade C (Good): C
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Grade E (Poor): 0
P-Reviewer: Hata M, Japan
Received: September 30, 2021
Peer-review started: September 30,
2021
First decision: March 7, 2022
Revised: March 9, 2022
Accepted: April 21, 2022
Article in press: April 21, 2022
Published online: May 20, 2022
Omer Sager, Ferrat Dincoglan, Selcuk Demiral, Bora Uysal, Hakan Gamsiz, Esra Gumustepe, Fatih
Ozcan, Onurhan Colak, Ahmet Tarik Gursoy, Cemal Ugur Dursun, Ahmet Oguz Tugcu, Galip
Dogukan Dogru, Rukiyye Arslan, Yelda Elcim, Esin Gundem, Bahar Dirican, Murat Beyzadeoglu,
Department of Radiation Oncology, Gulhane Medical Faculty, University of Health Sciences,
Ankara 0090, Turkey
Corresponding author: Omer Sager, MD, Associate Professor, Department of Radiation
Oncology, Gulhane Medical Faculty, University of Health Sciences, Ankara 0090, Turkey.
omersager@gmail.com
Abstract
Pilocytic astrocytoma (PA) may be seen in both adults and children as a distinct
histologic and biologic subset of low-grade glioma. Surgery is the principal
treatment for the management of PAs; however, selected patients may benefit
from irradiation particularly in the setting of inoperability, incomplete resection,
or recurrent disease. While conventionally fractionated radiation therapy has been
traditionally utilized for radiotherapeutic management, stereotactic irradiation
strategies have been introduced more recently to improve the toxicity profile of
radiation delivery without compromising tumor control. PAs may be suitable for
radiosurgical management due to their typical appearance as well circumscribed
lesions. Focused and precise targeting of these well-defined lesions under
stereotactic immobilization and image guidance may offer great potential for
achieving an improved therapeutic ratio by virtue of radiosurgical techniques.
Given the high conformality along with steep dose gradients around the target
volume allowing for reduced normal tissue exposure, radiosurgery may be
considered a viable modality of radiotherapeutic management. Another adv-
antage of radiosurgery may be the completion of therapy in a usually shorter
overall treatment time, which may be particularly well suited for children with
requirement of anesthesia during irradiation. Several studies have addressed the
utility of radiosurgery particularly as an adjuvant or salvage treatment modality
for PA. Nevertheless, despite the growing body of evidence supporting the use of
radiosurgery, there is need for a high level of evidence to dictate treatment
decisions and establish its optimal role in the management of PA. Herein, we
provide a concise review of radiosurgery for PA in light of the literature.
Sager O et al. Radiosurgery for pilocytic astrocytomas
WJEM https://www.wjgnet.com 37 May 20, 2022 Volume 12 Issue 3
Key Words: Pilocytic astrocytoma; Radiosurgery; Stereotactic irradiation; Low-grade glioma; Radiation
oncology; Children
©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
Core Tip: Radiosurgery for pilocytic astrocytomas may be utilized as part of initial management, as
adjuvant therapy, or for the salvage of recurrences. Radiosurgery offers a convenient procedure by a
condensed treatment schedule with rapid recovery. An improved toxicity profile may be achieved through
optimal normal tissue sparing. Accurate setup verification under stereotactic immobilization and image
guidance may be achieved, and the procedure is convenient with regards to staff and facility workload.
Citation: Sager O, Dincoglan F, Demiral S, Uysal B, Gamsiz H, Gumustepe E, Ozcan F, Colak O, Gursoy AT,
Dursun CU, Tugcu AO, Dogru GD, Arslan R, Elcim Y, Gundem E, Dirican B, Beyzadeoglu M. Concise review of
radiosurgery for contemporary management of pilocytic astrocytomas in children and adults. World J Exp Med
2022; 12(3): 36-43
URL: https://www.wjgnet.com/2220-315x/full/v12/i3/36.htm
DOI: https://dx.doi.org/10.5493/wjem.v12.i3.36
INTRODUCTION
Gliomas are neuroepithelial tumors arising from supporting glial cells of the central nervous system
(CNS). Low-grade glioma (LGG) may be seen in both adults and more commonly in the pediatric
population, and constitutes the most frequent CNS malignancy in children, accounting for approx-
imately one-third of pediatric brain tumors[1-3]. Pilocytic astrocytoma (PA), previously referred to as
polar spongioblastoma, cystic cerebellar astrocytoma, or juvenile PA (JPA), is a distinct histologic and
biologic subset of LGG initially described by Harvey Cushing in 1931[4,5]. The term “pilocytic” has been
used due to the microscopic appearance of cells with long, thin bipolar processes resembling hairs[5].
Rosenthal fibers may be typically found on hematoxylin and eosin staining as elongated eosinophilic
bundles. PA comprises roughly 25%-30% and 2%-5% of all CNS tumors in children and adults,
respectively[6,7]. These tumors are typically classified as World Health Organization (WHO) grade I
tumors[8]. The majority of PAs usually portend favorable prognosis with low growth rates; however, a
more aggressive clinical course may be observed in adult PAs and pilomyxoid astrocytomas[9,10]. PAs
mostly arise in the cerebellum, chiasmatic, and hypothalamic areas; nevertheless, these tumors may also
be seen at other locations including the cerebral hemispheres, brainstem, and spinal cord[11]. Surgery is
the main modality of management for PA, and gross total resection is intended to achieve tumor
eradication[12-14]. Observation has been considered given the relatively favorable prognosis to spare
patients from adverse effects of adjuvant therapy; however, failure to achieve optimal surgical tumor
removal may result in subsequent recurrences and the prognosis may be affected by age, disease
localization, and extent of resection[15-19]. In this context, radiation therapy (RT) may be considered for
the management of selected patients with PA. Irradiation has been shown to improve progression-free
survival (PFS) for PA; nevertheless, there have been concerns over the utility of RT due to the risk of
radiation-induced toxicity[19-25]. Since a significant proportion of patients with PA are children with
vulnerability to adverse effects of irradiation, several strategies have been introduced such as reserving
RT for salvage treatment for selected patients, decreasing the total delivered doses, and improving the
toxicity profile of radiation delivery through focused stereotactic irradiation[23-25].
Herein, we provide a concise review of radiosurgery for the management of PA in light of the
literature.
RADIOSURGERY FOR PA
PA comprises a considerable proportion of LGG particularly in the pediatric population. Typically, PAs
are well circumscribed WHO grade I tumors with low growth rates and indolent disease course. PAs
may present in the form of solid tumors or may include both cystic and solid components. While some
patients may have no symptoms until the tumors grow to a substantial size before diagnosis,
symptomatic presentation may occur depending on lesion location and association with critical
neurovascular structures. The disease course may also be affected by patient age with adult PAs
portending a typically poorer prognosis compared to JPA. Surgery is the principal therapy; however,
the extent of resection is a critical factor and patients undergoing incomplete surgical removal of the
Sager O et al. Radiosurgery for pilocytic astrocytomas
WJEM https://www.wjgnet.com 38 May 20, 2022 Volume 12 Issue 3
tumor may suffer from recurrences particularly within the first years of postoperative period[26]. While
there is no consensus on radiotherapeutic management, selected patients may benefit from irradiation
particularly in the setting of inoperability, incomplete resection, or recurrent disease. Conventionally
fractionated RT has been traditionally utilized for radiotherapeutic management. More recently,
stereotactic irradiation strategies have been introduced for improving the toxicity profile of radiation
delivery without jeopardizing disease control.
Radiosurgery in the forms of stereotactic radiosurgery (SRS), hypofractionated stereotactic RT
(HFSRT), and Stereotactic Body RT (SBRT) has been judiciously used for management of several CNS
disorders and tumors throughout the human body with promising therapeutic outcomes[27-41]. Unique
features of radiosurgical management include focused and precise targeting of well-defined tumors
under stereotactic immobilization and image guidance. Also, radiosurgery typically offers a condensed
treatment schedule, which may be particularly well suited for children with requirement of anesthesia
during irradiation. While conventionally fractionated RT is delivered over 5 to 6 wk, overall treatment
time is significantly reduced in radiosurgical management, which includes the delivery of a single or a
few fractions in a significantly shorter overall treatment time. Since a substantial proportion of patients
with PA are children, the requirement for daily anesthesia is a critical consideration and abbreviated
treatment with radiosurgery may offer a viable radiotherapeutic approach. Multiple convergent beams
are focused on the target to achieve excellent target coverage in radiosurgical applications. Steep dose
gradients around the target allow for optimal normal tissue sparing, which may be of utmost
importance for the management of children with PA to improve the toxicity profile of radiation
delivery. The need for expanding the target with margins to account for setup uncertainties is
eliminated or minimized under image guidance and robust stereotactic immobilization of the patients
which may contribute to reduced normal tissue exposure in radiosurgery of PAs. Table 1 shows
summarized data from selected series of stereotactic irradiation for management of PA in pediatric and
adult patients.
Murphy et al[42] assessed outcomes of Gamma Knife stereotactic radiosurgery (GKSRS) for PA.
Median patient age was 14 years (range: 2-84 years) at the time of GKSRS. Median tumor volume was
3.45 cc (range: 0.17-33.7 cc). Median margin dose was 14 Gy (range: 4-22.5 Gy). At last follow-up, 5- and
10-year overall survival (OS) rates were 95.7% and 92.5%, respectively, whereas 5- and 10-year PFS rates
were 74.0% and 69.7%, respectively. In this largest study of single session GKSRS including 141 patients
from 9 International Radiosurgery Research Foundation centers, the authors concluded that GKSRS
provided favorable long term PFS and OS[42].
Trifiletti et al[43] from the University of Virginia evaluated GK-based stereotactic irradiation in a
series of 28 patients with PA. Median age was 17.4 years (range: 2-70.3 years). Median tumor volume
was 1.84 cc and the median margin dose was 16 Gy. One patient received multi-fraction SRS with a total
dose of 15 Gy delivered in three fractions. Local tumor control rate was 93% without adverse radiation
effects. Actuarial PFS rates at 1, 3, 6, and 12 years were 96%, 96%, 96%, and 80%, respectively. Authors
concluded that favorable tumor control rates may be achieved by SRS as a viable technique for
management of PA in the primary or recurrent disease setting[43].
Simonova et al[44] assessed long-term outcomes with GK-based stereotactic irradiation for PA. Their
series included 25 pediatric patients with a median age of 13 years (range: 3-17 years). Median target
volume was 2.7 cc (range: 0.2-25 cc). The 10-year OS and PFS rates were 96% and 80%, respectively.
Patients with a planning target volume of 2.7 cc or less had increased PFS. Authors concluded that
radiosurgery offers an alternative treatment modality, providing long term local control for man-
agement of small residual or recurrent PAs[44].
Lizarraga et al[45] evaluated linear accelerator based stereotactic irradiation for progressive residual
PAs in a series of 12 patients. Median age at the start of stereotactic irradiation was 21 years (range: 5-41
years). There were no radiation-induced adverse effects in the follow-up period, and probabilities of
long-term PFS and disease-specific survival were 73.3% and 91.7%, respectively[45].
Hallemeier et al[46] assessed GKSRS for the management of recurrent or unresectable PA in a series of
18 patients treated at the Mayo Clinic. Median age at GKSRS was 23 years (range: 4-56 years). Median
treatment volume for GKSRS was 9.1 cc. Median margin dose was 15 and 16 Gy for patients with and
without prior RT, respectively. PFS rates were 65%, 41%, and 17% at 1, 5, and 10 years, respectively, at a
median follow-up duration of 8 years. OS rates were 94%, 71%, and 71%, at 1, 5, and 10 years after
GKSRS, respectively. The authors concluded that GKSRS may serve as a meaningful therapeutic option
for management of recurrent or unresectable PAs in the setting of treatment failure with surgery and/or
external beam RT considering the durable local tumor control and low permanent radiation induced
morbidity with GKSRS[46].
Kano et al[47] evaluated GKSRS for the management of newly diagnosed or recurrent JPAs in a series
of 50 pediatric patients with a median age of 10.5 years (range: 4.2-17.9 years). Median margin dose was
14.5 Gy. PFS after GKSRS (including tumor growth and cyst enlargement) was 91.7%, 82.8% and 70.8%
at 1, 3 and 5 years, respectively, for the entire series at a median follow-up duration of 55 mo. The
authors concluded that response to treatment was better in small volume residual solid JPAs, and
GKSRS should be considered when resection is not feasible or in the presence of early recurrence[47].
Sager O et al. Radiosurgery for pilocytic astrocytomas
WJEM https://www.wjgnet.com 39 May 20, 2022 Volume 12 Issue 3
Table 1 Selected series of stereotactic irradiation for management of pilocytic astrocytoma in pediatric and adult patients
Ref. Publication year
and study period Histology Number of
patients Age (yr) Setting Treatment Tumor size Dose Prior
RT
Follow-up
duration
PFS / tumor
control
Murphy et al
[42]
2019 (1990-2016) PA 141 Median age 14
yr (range: 2-84
yr)
As part of initial
management or
salvage therapy
GKSRS Median 3.45 cc Median margin dose 16 Gy 21
patients
Median 67.3 mo PFS 74.0% at 5
yr; PFS 69.7%
at 10 yr
Trifiletti et al
[43]
2017 (1990-2015) PA 28 Median age
17.4 yr (range:
2-70.3 yr)
As part of initial
management or
salvage therapy
GK-based SRS
or SRT
Median 1.84 cc Median margin dose 16 Gy for single
fraction SRS, and 15 Gy delivered in 3
fractions for SRT
4
patients
Median 5.4 yr PFS 96% at 6
yr; Tumor
control 93%
Simonova et al
[44]
2016 (1992-2002) PA 25 Median age 13
yr (range: 3-17
yr)
As part of initial
management or
salvage therapy
GK-based SRS
or SRT
Median 2.7 cc Median margin dose 16 Gy for
patients receiving single fraction,
median dose 25 Gy delivered in 5
fractions for SRT
2
patients
Median 15 yr PFS 80% at 10
yr
Lizarraga et al
[45]
2012 (1995-2010) PA 12 Median age 21
yr (range: 5-41
yr)
Salvage therapy LINAC-based
SRS or SRT
Median 6.5 cc for
SRT; Median 1.69
cc for SRS
Median dose 18.75 Gy for SRS and
median dose 50.4 Gy delivered in 28
fractions for SRT
0
patients
Median 37.5 mo PFS 73.3% at
long term
Hallemeier et al
[46]
2012 (1992-2005) PA 18 Median age 23
yr (range: 4-56
yr)
As part of initial
management or
salvage therapy
GKSRS Median 9.1 cc Median margin dose 15 Gy 10
patients
Median 8 yr PFS 41% at 5
yr; Tumor
control 75%
Kano et al[47] 2009 (1987-2006) PA 50 Median age
10.5 yr (range:
4.2-17.9 yr)
As part of initial
management or
salvage therapy
GKSRS Median 2.1 cc Median margin dose 14.5 Gy 5
patients
Median 55.5 mo PFS 70.8% at 5
yr
Kano et al[48] 2009 (1994-2006) PA 14 Median age 32
yr (range: 19-52
yr)
As part of initial
management or
salvage therapy
GKSRS Median 4.7 cc Median margin dose 13.3 Gy 6
patients
Median 36.3 mo PFS 31.5% at 5
yr
Hadjipanayis et
al[49]
2002(1987-2000) PA 37 Median age 14
yr (range: 3-52
yr)
As part of initial
management or
salvage therapy
GKSRS Median 3 cc Median margin dose 15 Gy 9
patients
Median 28 mo
after GKSRS
Tumor control
68%
Boëthius et al
[50]
2002 (1978-1997) PA 19 Mean age 10.6
yr (range: 2-60
yr)
Adjuvant therapy GKSRS Median 2.2 cc Median margin dose 10 Gy 2
patients
Median
radiological
follow-up 4.7 yr
Tumor control
94.7%
Somaza et al
[51]
1996 (1990-1993) PA 9 Mean age 8.6 yr
(range: 4-17 yr)
Adjuvant or salvage
therapy
GKSRS Mean tumor
diameter 16 mm
Median margin dose 15 Gy 2
patients
Median 19 mo Tumor control
100%
GKSRS: Gamma Knife stereotactic radiosurgery; LINAC: Linear accelerator; PA: Pilocytic astrocytoma; PFS: Progression-free survival; SRS: Stereotactic radiosurgery; SRT: Stereotactic radiation therapy.
In another study, Kano et al[48] separately assessed GKSRS for the management of PA in adult
patients. A total of 14 patients treated using GKSRS between 1994 and 2006 were included. Median age
was 32 years (range: 19-52 years). Median margin dose was 13.3 Gy, and median radiosurgery target
volume was 4.7 cc. At a median follow-up duration of 36.3 mo, 3 patients died and 11 patients were
Sager O et al. Radiosurgery for pilocytic astrocytomas
WJEM https://www.wjgnet.com 40 May 20, 2022 Volume 12 Issue 3
alive with OS rates of 100%, 88.9%, and 88.9% at 1, 3, and 5 years, respectively, for the entire series. The
authors emphasized that PA could behave more aggressively in adult patients, and thus additional
treatment strategies could be considered for unresectable PAs located in critical brain areas. The authors
concluded that GKSRS was most valuable for patients after maximal feasible surgical resection and
delayed cyst progression contributed to late loss of tumor control[48].
Hadjipanayis et al[49] performed a retrospective analysis of 37 patients receiving GKSRS at the
University of Pittsburgh Medical Center for recurrent or critically located PAs. Median age at GKSRS
was 14 years. At a median follow-up duration of 28 mo after GKSRS and 59 mo after diagnosis, 33 (89%)
of 37 patients were alive, providing a 7-year actuarial survival rate of 76%. Follow-up imaging revealed
tumor control in 25 (68%) of 37 patients. While 10 patients had complete resolution of tumor, 8 had
greater than 50% reduction in tumor volume. There were no procedure-related permanent morbidity or
mortality. The authors concluded that GKSRS could be used as part of multimodal management for
progressive, recurrent, or unresectable PAs and GKSRS could replace fractionated RT and
chemotherapy in selected patients as a safe and promising treatment modality[49].
Boëthius et al[50] evaluated outcomes of 19 patients receiving GKSRS for PA. Mean age was 10.6
years, and the study group included 16 pediatric patients. Median tumor volume was 2.2 cc. A median
marginal dose of 10 Gy was used given that majority of tumors were localized within or in close
neighborhood of the brainstem. A satisfactory tumor control rate of 94.7% was achieved at a median
radiological follow-up duration of 4.7 years and median clinical follow-up duration of 7 years albeit
with a relatively lower GKSRS dose[50].
Somaza et al[51] from Pittsburgh University assessed the utility of GKSRS in adjuvant treatment of 9
pediatric patients with growing and unresectable deeply seated PAs. Mean margin dose was 15 Gy. At a
mean follow-up duration of 19 mo, tumor control was achieved in all patients with significant tumor
shrinkage in 5 patients and no further growth in 4 patients. No patients had early or late toxicity. The
authors concluded that GKSRS served as a safe and effective therapeutic modality for management of
deeply seated and small volume PAs[51].
Overall, stereotactic irradiation has been utilized for management of PA in both children and adults
as a promising treatment modality. Since adverse effects of irradiation constitute major concerns over
the use of RT for treatment of PAs, improving the toxicity profile of radiation delivery is a critical aspect
of contemporary patient management in the millennium era. Within this context, focused and precise
targeting of well circumscribed PAs under stereotactic immobilization and image guidance may offer
great potential for achieving an improved therapeutic ratio by virtue of radiosurgical techniques.
Another advantage of radiosurgery may be the completion of therapy in a usually shorter overall
treatment time, which may be particularly well suited for children with requirement of anesthesia
during irradiation. Although radiosurgery is a relatively newer treatment paradigm compared to
conventional RT, it has gained widespread popularity and adoption with growing body of evidence
supporting its utility. Nevertheless, there is still room for further improvements with the need for high
level of evidence to reach multidisciplinary consensus for optimal management of PAs.
CONCLUSION
PA may be seen in both adults and children as a distinct histologic and biologic subset of LGG. Surgery
is the principal treatment for management of PAs, however, selected patients may benefit from
irradiation particularly in the setting of inoperability, incomplete resection, or recurrent disease. While
conventionally fractionated RT has been traditionally utilized for radiotherapeutic management,
stereotactic irradiation strategies have been introduced more recently to improve the toxicity profile of
radiation delivery without compromising tumor control. PAs may be suitable for radiosurgical
management due to their typical appearance as well circumscribed lesions. Focused and precise
targeting of these well-defined lesions under stereotactic immobilization and image guidance may offer
great potential for achieving an improved therapeutic ratio by virtue of radiosurgical techniques. Given
the high conformality along with steep dose gradients around the target volume allowing for reduced
normal tissue exposure, radiosurgery may be considered as a viable modality of radiotherapeutic
management. Another advantage of radiosurgery may be the completion of therapy in a usually shorter
overall treatment time, which may be particularly well suited for children with requirement of
anesthesia during irradiation.
Although radiosurgery has a shorter history compared to conventional RT, there is accumulating data
on its utility for management of several tumors throughout the human body. In the context of PAs,
several studies have addressed its use particularly as an adjuvant or salvage treatment modality.
Nevertheless, despite the growing body of evidence supporting the utility of radiosurgery, there is need
for high level of evidence to dictate treatment decisions and establish its optimal role in management of
PA. We believe that both SRS and SRT may be considered as viable radiosurgical methods for
management of PA and selection between SRS and SRT should be based on patient, tumor, and
treatment characteristics.
Sager O et al. Radiosurgery for pilocytic astrocytomas
WJEM https://www.wjgnet.com 41 May 20, 2022 Volume 12 Issue 3
In the context of future perspectives, immunotherapy, identification of driver alterations and
introduction of efficacious targeted therapies may pave the way for contemporary treatment approaches
for PAs. Further extensive investigation is warranted to develop safe and effective treatment strategies
for management of PAs.
FOOTNOTES
Author contributions: Sager O, Dincoglan F, Demiral S, Uysal B, Gamsiz H, Gumustepe E, Ozcan F, Colak O, Gursoy
AT, Dursun CU, Tugcu AO, Dogru GD, and Arslan R played significant roles in data acquisition, interpretation of
data, and reviewing and writing of the manuscript; Elcim Y, Gundem E, and Dirican B revised the manuscript for
important intellectual content; Beyzadeoglu M took part in designing, reviewing, and writing the manuscript and
revising the manuscript for important intellectual content; All authors have read and approved the final manuscript.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by
external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-
NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license
their derivative works on different terms, provided the original work is properly cited and the use is non-
commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Country/Territory of origin: Turkey
ORCID number: Omer Sager 0000-0001-7866-2598; Ferrat Dincoglan 0000-0002-7668-0976; Selcuk Demiral 0000-0002-3408-
0323; Bora Uysal 0000-0002-7288-7005; Hakan Gamsiz 0000-0002-7791-3487; Esra Gumustepe 0000-0002-3664-4663; Fatih
Ozcan 0000-0002-1965-7067; Onurhan Colak 0000-0003-1421-4678; Ahmet Tarik Gursoy 0000-0002-9404-4578; Cemal Ugur
Dursun 0000-0001-6095-3506; Ahmet Oguz Tugcu 0000-0001-6229-9405; Galip Dogukan Dogru 0000-0002-4906-8087;
Rukiyye Arslan 0000-0003-2835-5893; Yelda Elcim 0000-0001-6274-1267; Esin Gundem 0000-0002-9482-8567; Bahar Dirican
0000-0002-1749-5375; Murat Beyzadeoglu 0000-0003-1035-7209.
S-Editor: Ma YJ
L-Editor: Filipodia
P-Editor: Ma YJ
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