Classical tandem-source dwelling covering the entire uterus: essential in modern intracavitary radiotherapy for cervical cancer?
OBJECTIVE
We investigated whether conventional tandem-source dwelling to cover the entire uterus, classically regarded as the target volume, is necessary in modern intracavitary radiotherapy (ICRT) for cervical cancer.


METHODS
The study included 95 cervical squamous cell carcinoma patients treated by high-dose-rate ICRT (point A dose was 6.0 Gy, with three to five insertions per patient) after external beam radiotherapy (EBRT), with central pelvic doses of 12-50 Gy. The tandem-source dwell length was adjusted to the target volume specified by magnetic resonance (MR) imaging. A tandem applicator was inserted as far as the uterine fundus in accordance with the post-EBRT MR-assessed cavity length. The pre-EBRT MR-specified target volume was used for the dwell-length adjustment. The safety of the dwell-length adjustment was assessed in terms of treatment failure.


RESULTS
The dwell-length adjustment was made in 248 of 366 total insertions with a dwell-length reduction of 5-55 mm (median 15 mm) at the corpus. Pelvic failure was identified in 22 patients with a 2-year pelvic disease-free survival rate of 75.6% but without evidence of failure at dwelling-skipped corpuses.


CONCLUSIONS
Given after pelvic EBRT and ICRT of full-length dwelling in part, which may have eradicated possible subclinical extension, adjustment of the tandem-source dwell length to the MR-specified target volume appeared to be safe.
Ohara
Kiyoshi
K
Department of Radiation Oncology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan. ki-ohara@md.tsukuba.ac.jp
Nemoto
Keiko
K
Ohnishi
Kayoko
K
Hashimoto
Takayuki
T
Fukumitsu
Nobuyoshi
N
Hata
Masaharu
M
Sugahara
Shinji
S
Tokuuye
Koichi
K
Akine
Yasuyuki
Y
D001918:Brachytherapy; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D011879:Radiotherapy Dosage; D002583:Uterine Cervical Neoplasms / Q000532:radiotherapy*