The purpose is to compare CT-based dosimetry with International Commission on Radiation Units and Measurements (ICRU 38) bladder and rectum reference points in patients of carcinoma of uterine cervix treated with intracavitary brachytherapy (ICA). Twenty-two consecutive patients were evaluated. Orthogonal radiographs and CT images were acquired and transferred to PLATO planning system. Bladder and rectal reference points were identified according to ICRU 38 recommendations. Dosimetry was carried out based on Manchester system. Patient treatment was done using (192)Iridium high dose rate (HDR) remote after-loading machine based on the conventional radiograph-based dosimetry. ICRU rectal and bladder point doses from the radiograph plans were compared with D(2), dose received by 2 cm(3) of the organ receiving maximum dose from CT plan. V(2), volume of organ receiving dose more than the ICRU reference point, was evaluated. The mean (+/-standard deviation) volume of rectum and bladder was 60 (+/-28) cm(3) and 138 (+/-41) cm(3) respectively. The mean reference volume in radiograph and CT plan was 105 (+/-7) cm(3) and 107 (+/-7) cm(3) respectively. It was found that 6 (+/-4) cm(3) of rectum and 16 (+/-10) cm(3) of bladder received dose more than the prescription dose. V(2) of rectum and bladder was 7 (+/-1.7) cm(3) and 20.8 (+/-6) cm(3) respectively. Mean D(2) of rectum and bladder was found to be 1.11 (+/-0.2) and 1.56 (+/-0.6) times the mean ICRU reference points respectively. This dosimteric study suggests that comparison of orthogonal X-ray-based and CT-based HDR ICA planning is feasible. ICRU rectal point dose correlates well with maximum rectal dose, while ICRU bladder point underestimates the maximum bladder dose.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2786096 | PMC |
http://dx.doi.org/10.4103/0971-6203.39417 | DOI Listing |
J Appl Clin Med Phys
January 2025
Department of Radiation Medicine and Applied Sciences, UC San Diego Health, La Jolla, California, USA.
Purpose: Daily online adaptive radiotherapy (ART) improves dose metrics for gynecological cancer patients, but the on-treatment process is resource-intensive requiring longer appointments and additional time from the entire adaptive team. To optimize resource allocation, we propose a model to identify high-priority patients.
Methods: For 49 retrospective cervical and endometrial cancer patients, we calculated two initial plans: the treated standard-of-care (Initial) and a reduced margin initial plan (Initial) for adapting with the Ethos treatment planning system.
Int J Radiat Oncol Biol Phys
January 2025
The Royal Marsden NHS Foundation Trust, London SM2 5PT, UK; Radiotherapy and Imaging Division, Institute of Cancer Research, London SM2 5NG, UK.
Purpose: In the PACE-B study, a non-randomised comparison of toxicity outcomes between stereotactic body radiotherapy (SBRT) platforms revealed fewer urinary side-effects with CyberKnife (CK) compared to conventional linac (CL) SBRT. This analysis compares baseline characteristics and planning dosimetry between the CK-SBRT and CL-SBRT cohorts in PACE-B, aiming to provide insight into possible reasons for differing toxicity outcomes between the platforms.
Methods: Dosimetric parameters for the surrogate urethra (SU), contoured urethra, bladder, bladder trigone (BT), and rectum were extracted from available CT planning scans of PACE-B SBRT patients.
Curr Oncol
January 2025
Department of Radiation Oncology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
(1) Background: Volumetric modulated arc therapy (VMAT) can deliver more accurate dose distribution and reduce radiotherapy-induced toxicities for postoperative cervical and endometrial cancer. This study aims to retrospectively analyze the relationship between dosimetric parameters of organs at risk (OARs) and acute toxicities and provide suggestions for the dose constraints. (2) Methods: A total of 164 postoperative cervical and endometrial cancer patients were retrospectively analyzed, and the endpoints were grade ≥ 2 acute urinary toxicity (AUT) and acute lower gastrointestinal toxicity (ALGIT).
View Article and Find Full Text PDFCurr Oncol
December 2024
Carol Davila University of Medicine and Pharmacy, 020021 Bucharest, Romania.
Vulvar cancer is one of the rarest gynecological malignancies. The development of this condition can be associated with either dysplasia linked to human papillomavirus (HPV), primarily affecting younger women, or vulvar dermatoses such as lichen sclerosus, which predominantly affect older women. Over the last decade, the incidence of vulvar cancer has risen by 0.
View Article and Find Full Text PDFRadiol Oncol
January 2025
1State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong Province, China.
Background: This study evaluates the contouring variability among observers using MR images reconstructed by different sequences and quantifies the differences of automatic segmentation models for different sequences.
Patients And Methods: Eighty-three patients with pelvic tumors underwent T1-weighted image (T1WI), contrast enhanced Dixon T1-weighted (T1dixonc), and T2-weighted image (T2WI) MR imaging on a simulator. Two observers performed manual delineation of the bladder, anal canal, rectum, and femoral heads on all images.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!