Dosimetric Comparison between High Dose Rate Brachytherapy Boost and Volumetric Arc Therapy Boost in Locally Advanced Cancer Cervix

Abstract

Concurrent chemoradiotherapy is considered the standard treatment for the locally advanced cancer cervix (LACC). Radiotherapy is commonly administered by a three-dimensional conformal radiotherapy (3DCRT) approach followed by brachytherapy (BT). High dose rate (HDR) BT is commonly administered; however, several drawbacks exist including invasive technique, pain, requirement of anesthesia, and operative risks. We assessed the dosimetric difference between the HDR BT and the volumetric modulated arc therapy (VMAT) boost in those patients. Ten patients were selected retrospectively with LACC and all received whole pelvis radiotherapy followed by BT boost of 7 Gy in three fractions. The computed tomography (CT) image was transferred to the Varian system for the VMAT plan while the one with the applicator was transferred to the Sagi planning system and the high-risk clinical target volume (HR-CTV), bladder, rectum, sigmoid, and small bowel were delineate with a margin of 5 mm were added to the CTV to create the planning target volume (PTV). The D90 for the PTV in VMAT boost was lower than received by the HR-CTV in the BT boost. Mean volume of the PTV was higher than that of the HR-CTV. The D2cc was higher in VMAT for bladder, sigmoid, and rectum while the D2cc for the small bowel in BT was higher compared with the VMAT. The VMAT is an option that exists for patients who refuse BT or cannot tolerate it, or in case of nonavailability of BT or a nonworking machine.

Brachytherapy infrastructure in sub-Saharan Africa and quest for cervical cancer elimination

“…Currently, in numerous nations, including Nigeria, Ghana, Zimbabwe, and Botswana [15][16][17], HDR afterloaders are used (Table 2). Although there is no evidence to suggest that LDL and HDL techniques have any impact on clinical outcomes [18], HDR has the advantage of reducing staff's and patient's radiation exposure and can treat more patients each week than LDR [19]. One advantage of LDR is that the radioisotope generally utilized is cesium-137, which has a 30-year halflife.…”

“…On the other hand, the HDR sources (iridium-192 has a half-life of 74 days, and cobalt-60 has a half-life of 5.3 years) have a shorter half-life, and hence require regular replacement. This presents significant logistical and regulatory issues for countries, which use these radioisotopes [15][16][17][18][19][20][21][22][23][24][25].…”

Building a sustainable future: Closing the gap in radiotherapy and brachytherapy resources to achieve the sustainable development agenda 2030 goals for cervical cancer control in Africa

“…The special assessment of cobalt-60 teletherapy equipment, whose usage has decreased correspondingly in favour of linear accel- The World Health Assembly (WHA) 2020 approved the worldwide policy to expedite the eradication of cervical cancer as a global health issue and its related objectives and goals for the years 2020-2030 (Hegazy et al, 2021;World Health Assembly, 2020). This worldwide initiative includes a target of 90% of women with infiltrative cervical cancer receiving therapy.…”

“…In recent times, there has been a steady transition from delivering LDR brachytherapy to HDR across the continent. HDR afterloaders are actively operational in many countries, such as Botswana, Zimbabwe, Ghana and Nigeria (Clayman, 2015; Hegazy et al, 2021; Scott et al, 2021). Despite the lack of evidence indicating any difference between HDL and LDL procedures in terms of clinical outcomes (Chibonda et al, 2021), HDR offers the benefit of decreasing the rate at which patients, as well as staff, are being exposed to radiation and can serve more patients per weekly than LDR (Hegazy et al, 2021).…”

“…To prevent moments without brachytherapy facilities, the specific radioisotope should be carefully chosen with regard to its changing frequency. The majority of African nations are currently choosing to use cobalt‐60 radioisotope for HDR brachytherapy because they have a shorter treatment period and longer half‐life and are consequently financially feasible without compromising outcomes (Hegazy et al, 2021). Without a more significant annual improvement of publicly available brachytherapy and external beam radiotherapy centres, than is indicated in this study, the WHA (2020) goal will not be achievable.…”