Delineating the relationship between Point A prescription dose and pelvic lymph node doses in intracavitary high-dose-rate brachytherapy treatment of cervical cancer for use in low- and middle-income countries Journal Article


Authors: Weaver, J; Harmon, G; Harkenrider, M. M.; Surucu, M; Wood, A; Alite, F; Small, W., Jr
Article Title: Delineating the relationship between Point A prescription dose and pelvic lymph node doses in intracavitary high-dose-rate brachytherapy treatment of cervical cancer for use in low- and middle-income countries
Abstract: PURPOSE: To define the relationship between the Point A prescription dose and the dose delivered to various pelvic lymph node groups during high-dose-rate (HDR) brachytherapy treatment of cervical cancer. In less developed countries, brachytherapy is often done without three-dimensional image guidance, instead relying on plain radiography and prescription to Point A. A defined relationship between Point A dose and lymph node doses would help physicians in these health care settings to more accurately estimate nodal doses. METHODS AND MATERIALS: Treatment data from 50 fractions of HDR brachytherapy of cervical cancer were reviewed, the pelvic lymph nodes were contoured, and dose-volume histogram parameters were obtained. Dose-volume histogram parameters for each contour were normalized as a percentage of the corresponding Point A dose. All nodal groups were divided into left and right sides, except the presacral nodal group. RESULTS AND CONCLUSIONS: Mean Point A doses were bilateral (Bil) 5.92 Gy +/- 0.58, left (L) 5.93 +/- 0.59, and right (R) 5.92 +/- 0.59. Mean normalized D90 values for the various lymph node groups were as follows-obturator: Bil 20.3% +/- 4.5, L 20.5% +/- 4.4, and R 20.2% +/- 5.2; external iliac: Bil 9.5% +/- 2.9, L 10.0% +/- 3.1, and R 9.5% +/- 3.0; internal iliac: Bil 12.2% +/- 3.5, L 12.1% +/- 3.4, and R 12.9% +/- 4.7; common iliac: Bil 4.3% +/- 1.6, L 4.3% +/- 1.6, and R 4.3% +/- 1.7; and presacral: 8.7% +/- 3.4. These relationships can serve as a useful tool for evaluating lymph node doses during HDR brachytherapy of cervical cancer in facilities performing two-dimensional treatment planning and those with limited resources.
Keywords: Radiation Oncology; Cervical cancer; Point A; Lymph nodes; Nodal boost; Pelvic lymph nodes; Prescription dose
Journal Title: Brachytherapy
Volume: 17
Issue: 1
ISSN: 1873-1449; 1538-4721
Publisher: Elsevier Inc  
Journal Place: United States
Date Published: 2018
Start Page: 201
End Page: 207
Language: eng
DOI/URL:
Notes: LR: 20180216; CI: Copyright (c) 2017; JID: 101137600; OTO: NOTNLM; 2017/07/05 00:00 [received]; 2017/09/01 00:00 [revised]; 2017/09/05 00:00 [accepted]; 2017/10/27 06:00 [pubmed]; 2017/10/27 06:00 [medline]; 2017/10/26 06:00 [entrez]; ppublish