Correlation between patients’ anatomical characteristics and interfractional internal prostate motion during intensity modulated radiation therapy for prostate cancer

Shintaroh Maruoka, Yasuo Yoshioka, Fumiaki Isohashi, Osamu Suzuki, Yuji Seo, Yuki Otani, Yuichi Akino, Yutaka Takahashi, Iori Sumida, Kazuhiko Ogawa

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

Intensity modulated radiation therapy (IMRT) is one of a standard treatment for localized prostate cancer. Although lower complication is expected for smaller target margin, determination of optimal margin is important. For bony-structure based registration, internal prostate motion is the main factor determining the margin from clinical target volume to planning target volume. The purpose of this study was to measure interfractional internal motion of the prostate and to identity the factors which enlarge or reduce the margin, with special focus on patients’ anatomical characteristics. The 586 image sets of 16 patients acquired with megavoltage cone beam computed tomography were analyzed. For each patient, prostate shift in three directions was recorded for each fraction to calculate the required margin. Correlations between these values and patients’ anatomical characteristics were evaluated. The posteriorly required margin correlated positively with rectal volume and rectal mean area (p = 0.015 and p = 0.008), while random error in lateral, craniocaudal and anteroposterior direction correlated negatively (p = 0.014, 0.04 and 0.0026, respectively) with body mass index (BMI). In addition to the previously identified factor of distended rectum, BMI was newly identified as another significant factor influencing interfractional internal prostate motion.

Original languageEnglish (US)
Article number579
JournalSpringerPlus
Volume4
Issue number1
DOIs
StatePublished - Dec 1 2015

Keywords

  • Body mass index
  • Interfractional motion
  • Internal motion
  • Megavoltage cone beam computed tomography
  • Prostate cancer

Fingerprint Dive into the research topics of 'Correlation between patients’ anatomical characteristics and interfractional internal prostate motion during intensity modulated radiation therapy for prostate cancer'. Together they form a unique fingerprint.

Cite this