Page 38 - ARNM-1-2

Advances in Radiotherapy
& Nuclear Medicine Single-channel applicators for cervical cancer

A

B

Figure 3. Sectional and three-dimensional dose distributions between SCA and tandem. Isodose curve of SCA and tandem on coronal, sagittal, and cross-
sectional views (from inner to outer representing isodose curves of 150%, 100% and 70%, respectively (shown in Table 1).
Abbreviations: SCA: Single-channel applicator.
Table 1. Different areas of 100% dose curves between SCA and cGy and 8.23 cGy, respectively. The reduction ratios of the
tandem SCA at points B and R were 21.5% and 17.6%, respectively
(Table 3), thus completing the preliminary identification.
Tandem (cm ) SCA (cm ) Difference (%)
2
2
Coronal plane 40.87±1.01 40.11±1.01 1.86±0.14 3.4. Dosimetry between the SCA and FAS in
Sagittal plane 40.02±0.47 35.89±0.68 10.32±0.92 41 patients with cervical cancer
Cross-sectional plane 32.35±0.62 26.01±0.20 19.59±0.95 The dosimetric results on a TLD at point B showed a mean
Notes: SCA was almost the same as tandem on the coronal axis; SCA dose of 232.83 ± 23.33 cGy for the SCA in 19 patients,
was smaller than tandem on the sagittal and cross-sectional axes. compared with a mean dose of 236.0 ± 17.49 cGy for
Abbreviations: TLD: Thermoluminescent dosimeter; the FAS in 22 patients. The results indicate no significant
SCA: Single-channel applicator.
difference (P = 0.903). At point R, the mean dose for the
at points A, B, and R were 3.18%, 24.88%, and 26.58%, SCA was 510.2 ± 27.20 cGy, while the mean dose for the
respectively (Table 2). Dosimetry findings with a TLD on FAS was 538.6±18.35 cGy, also showing no significant
the CFAP revealed that the SCA could effectively reduce difference (P = 0.381; Figure 4). The patient and disease
the irradiation to points B and R. characteristics at baseline, treated with the SCA and FAS,
are shown in Table 4. There was no significant difference
3.3. Preliminary dosimetry comparison between in baseline data between the two groups. The SCA was
the SCA and tandem in 6 patients treated with a low found to be as safe as FAS when used as an applicator of
dose of 20 cGy intracavitary brachytherapy in cervical cancer.

A total of six patients, aged 28 – 56 years, were enrolled 4. Discussion
in a clinical trial between 2009 and 2010 after providing
informed consent to participate. They agreed to receive Recommendations for the treatment of cervical cancer
an additional 20 cGy as part of the last fraction of are based on the clinical stage. At present, patients with
brachytherapy. When 20 cGy was administered using stage IA1 cervical cancer usually undergo a hysterectomy
each applicator, the absorbed irradiation doses of the SCA due to the low incidence of lymph node metastasis, while
at points B and R were approximately 5.06 cGy and 6.79 patients with IA2 to IIA disease have the option of surgery
cGy, respectively, while those of the tandem were 6.43 or radiotherapy, both of which are equally effective. Lymph

Volume 1 Issue 2 (2023) 4 https://doi.org/10.36922/arnm.0322