Aim: To evaluate Radiation Therapy Oncology Group planning target volume margins of 7-10 mm for radiation therapy in anorectal cancer using prone belly-board positioning without image guidance.

Patients And Methods: 375 kV cone beam computed tomography image-guided radiotherapy (IGRT) images from 20 patients treated for anorectal cancer were retrospectively analyzed for setup shifts. We calculated the total translational shift for each patient and the frequency with which setup shifts exceeded 7 mm and 10 mm.

Results: A total of 42.7% of treatments required shifts >7 mm and 20.8% >10 mm. The mean translational shift was 7.1 mm. 70% of patients experienced shifts ≥7 mm in 20% or more of their treatments and 25% of ≥10 mm in 20% or more of their treatments; 15% experienced shifts ≥10 mm in over half of their treatments. van Herk calculations suggest margins of 12.8 mm are necessary for accuracy without IGRT.

Conclusion: IGRT using a prone belly board and 7-10 mm margins requires daily image-guidance to prevent planning target volume misses and ensure optimal dose delivery.

Download full-text PDF

Source

Publication Analysis

Top Keywords

anorectal cancer
12
image-guided radiotherapy
8
cancer prone
8
prone belly-board
8
belly-board positioning
8
radiation therapy
8
planning target
8
target volume
8
setup shifts
8
translational shift
8

Similar Publications

Introduction: Anorectal melanoma (ARM) is rare and highly lethal neoplasm. It has a poorer prognosis compared with cutaneous ones. Sentinel lymph node biopsy (SLNB) has become the preferred method of nodal staging method for cutaneous melanoma.

View Article and Find Full Text PDF

Clinicopathological features of Lynch syndrome pedigrees with MSH2 c.351G>A gene variant.

Mol Genet Genomic Med

January 2025

Department of General Surgery, The Fourth Affiliated Hospital, China Medical University, Shenyang, Liaoning, China.

Background: Lynch syndrome (LS) is an autosomal-dominant disorder that increases the risk of many cancers. To identify novel or rare pathogenic variants of MMR genes associated with LS, especially in Chinese pedigrees.

Methods: One four-generation Chinese Han family from northeast China with 29 members was enrolled.

View Article and Find Full Text PDF

Triggering receptor expressed in myeloid cells-1 (TREM1) is an important regulator of innate and adaptive immunity, which can directly amplify an inflammatory response. Current studies have found the immunomodulatory role of TREM1 in tumor microenvironment. However, the role of TREM1 in ovarian cancer (OV) remains unclear.

View Article and Find Full Text PDF

Introduction: Data regarding the incidence and outcomes of mismatch repair deficient (dMMR) rectal cancer is limited. This study characterizes dMMR rectal cancer patients, comparing response after neoadjuvant radiotherapy and oncological outcomes to mismatch repair proficient (pMMR) rectal cancer patients.

Method: A retrospective cross-sectional cohort study was conducted in 67 Dutch centers.

View Article and Find Full Text PDF

Real-World Evidence of the Prevalence of Driver Mutations in Anorectal Melanoma.

Mol Diagn Ther

December 2024

Comprehensive Cancer Center, University of Maastricht, Maastricht University Medical Center, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.

Introduction: Anorectal melanoma is a rare neoplasm with an aggressive behavior and poor prognosis. Recently, recurrent gene mutations related to anorectal melanoma have been identified in a small series of cases, and this holds promise for targeted therapies, analogous to cutaneous melanoma. The purpose of this study was to analyze testing rates and prevalence of mutations in anorectal melanoma in the Dutch population.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!