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Advances in Radiotherapy
& Nuclear Medicine Outcomes of durations in 2D and 3D BT for CCA

1. Introduction used a cutoff of 55 days and revealed significant differences
in the 5-year survival and pelvic control rates between
Cervical cancer is the third most common gynecologic patients who were treated for <55 days and those who were
malignancy in developed countries and the second most treated for ≥55 days (5-year OS, 65% vs. 54%, P = 0.03;
common cancer among women in developing nations. pelvic control rate, 87% vs. 72%, P = 0.006). Based on
Clinical management of cervical cancer primarily involves these findings, the current international radiation therapy
surgery and radiation therapy, and the concurrent use guidelines recommend the completion of radiotherapy for
of chemoradiotherapy is the mainstay in patients in the cervical cancer within 8 weeks (56 days).
advanced stage. Several studies have demonstrated that
brachytherapy plays a pivotal curative role in locally Based on the findings of the aforementioned studies,
advanced cervical cancer, contributing to an improved we used a threshold of 56 days in our study. We aimed to
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prognosis. However, the conventional approach of evaluate the differences in survival, treatment techniques,
combining external beam radiation therapy (EBRT) and other variables between patients treated for ≤ 56 days
with intracavitary brachytherapy (BT) remains a critical and those treated for > 56 days. The objective of this study
therapeutic strategy for cervical cancer. According to was to identify any correlations and significant distinctions
the American Society for Radiation Oncology’s Clinical in these groups. Through data analysis, we aimed to
Practice Guideline titled “Radiation Therapy for Cervical determine whether the duration of radiation treatment
Cancer: Executive Summary of an ASTRO Clinical impacts the survival outcomes of patients with cervical
Practice Guideline,” brachytherapy is an indispensable cancer. The findings of this study can help better tailor the
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component in the management of cervical cancer. Based scheduling of surgical and radiation oncologists, enhance
on the cervical cancer radiation dose and multifaceted patient compliance, and provide guidance for clinical
biological factors, the recommended course of cervical practice.
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cancer radiation therapy, which encompasses the first
phase of EBRT and the second phase of BT, should be 2. Materials and methods
completed within 8 weeks. According to the American 2.1. General information
Brachytherapy Society’s consensus guidelines for locally
advanced cervical cancer, the recommended tumor point We retrospectively collected the medical records of
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649 patients with cervical cancer who were treated with
(point A) dose ranges from 80 to 90 Gy equivalent dose in
2-Gy fractions, which can be adjusted based on the tumor concurrent intensity-modulated radiation therapy (IMRT)
size during brachytherapy. and intracavitary brachytherapy at our institution from
2014 to 2019. The clinical data of all the patients were
A retrospective study conducted by Song et al. in extracted from the outpatient or inpatient records. All
2013 demonstrated that patients with cervical cancer patients had undergone standard physical examinations,
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who were administered concurrent chemoradiotherapy abdominal–pelvic computed tomography (CT) scans,
for local pelvic control for >56 days experienced adverse enhanced magnetic resonance imaging of the pelvic, or
effects on pelvic local control. This may have led to an positron emission tomography–CT scans. The tumor
increase in pelvic control failure cases, a decrease in samples were subjected to histopathological evaluation,
disease-specific survival rates, and a reduction in overall and the findings were consistent with the pathological
survival (OS). Fyles et al. demonstrated that the treatment diagnostic criteria for cervical cancer.
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duration significantly impacts pelvic local control. Their
study employed mathematical models based on the The patients were categorized into two groups on the basis
linear-quadratic theory and analytical methods such as of the total duration of radiation therapy. The observation
logistic regression and Cox regression. They found that group (OG; duration >56 days) included 464 cases
by providing brachytherapy for >30 days as the definitive (71.5%), and the control group (CG; duration ≤56 days)
treatment for cervical cancer, the control rate in the pelvic included 185 cases (28.5%). The patient age ranged from
area decreased by approximately 1% daily. Furthermore, 29 to 88 years, with 370 patients (57.0%) aged ≤55 years
cancer stage and age were identified as high-risk factors old and 279 patients (43.0%) aged >55 years. All patients
of reduced pelvic control. Perez et al. also confirmed that were concurrently administered IMRT and intracavitary
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prolonging the treatment duration in patients with stage brachytherapy. Brachytherapy was administered as two-
IB, IIA, IIB, and III cervical cancer significantly affects dimensional (2D) radiation therapy in 525 patients and
pelvic tumor control and disease-specific survival rates. three-dimensional (3D) brachytherapy in 124 patients.
The prolongation of treatment results in a daily decrease of Based on the disease staging, 18, 93, 373, 24, 104, 18,
approximately 0.85% in pelvic tumor control. Petereit et al. and 19 patients had stage IB, IIA, IIB, IIIA, IIIB, IIIC, and
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Volume 2 Issue 4 (2024) 2 doi: 10.36922/arnm.4310