Rectal Dose and Source Strength of the High-Dose-Rate Iridium-192 Both Affect Late Rectal Bleeding After Intracavitary Radiation Therapy for Uterine Cervical Carcinoma

Fumiaki Isohashi, Yasuo Yoshioka, Masahiko Koizumi, Osamu Suzuki, Koji Konishi, Iori Sumida, Yutaka Takahashi, Toshiyuki Ogata, Tadayuki Kotsuma, Takehiro Inoue

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

Purpose: The purpose of this study was to reconfirm our previous findings that the rectal dose and source strength both affect late rectal bleeding after high-dose-rate intracavitary brachytherapy (HDR-ICBT), by using a rectal dose calculated in accordance with the definitions of the International Commission on Radiation Units and Measurements Report 38 (ICRURP) or of dose-volume histogram (DVH) parameters by the Groupe Européen de Curietherapie of the European Society for Therapeutic Radiology and Oncology. Methods and Materials: Sixty-two patients who underwent HDR-ICBT and were followed up for 1 year or more were studied. The rectal dose for ICBT was calculated by using the ICRPRP based on orthogonal radiographs or the DVH parameters based on computed tomography (CT). The total dose was calculated as the biologically equivalent dose expressed in 2-Gy fractions (EQD2). The relationship between averaged source strength or the EQD2 and late rectal bleeding was then analyzed. Results: When patients were divided into four groups according to rectal EQD2 (≥ or <median dose) and source strength (≥ or <2.4 cGy.m2.h-1), the group with both a high EQD2 and a high source strength showed a significantly greater probability of rectal bleeding for ICRURP, D2cc, and D1cc. The patients with a median rectal dose above the threshold level did not show a greater frequency of rectal bleeding unless the source strength exceeded 2.4 cGy.m2.h-1. Conclusions: Our results obtained with data based on ICRURP and CT-based DVH parameters indicate that rectal dose and source strength both affect rectal bleeding after HDR-ICBT.

Original languageEnglish (US)
Pages (from-to)758-764
Number of pages7
JournalInternational Journal of Radiation Oncology Biology Physics
Volume77
Issue number3
DOIs
StatePublished - 2010

Keywords

  • High-dose rate
  • Intracavitary brachytherapy
  • Ir
  • Late rectal complications
  • Source strength

Fingerprint

Dive into the research topics of 'Rectal Dose and Source Strength of the High-Dose-Rate Iridium-192 Both Affect Late Rectal Bleeding After Intracavitary Radiation Therapy for Uterine Cervical Carcinoma'. Together they form a unique fingerprint.

Cite this