Image-guided brachytherapy for cervical cancer: Analysis of D2 cc hot spot in three-dimensional and anatomic factors affecting D2 cc hot spot inorgans at risk

Academic Article


  • Purpose: To analyze the D2 cc hot spot in three-dimensional CT and anatomic factors affecting the D2 cc hot spot in organs at risk (OARs). Methods and Materials: Thirty-one patients underwent pelvic CT scan after insertion of the applicator. High-dose-rate treatment planning was performed with standard loading patterns. The D2 cc structures in OARs were generated in three dimensional if the total equivalent dose in 2Gy exceeded our defined dose limits (hot spot). The location of D2 cc hot spot was defined as the center of the largest D2 cc fragment. The relationship between the hot spot and the applicator position was reported in Digital Imaging and Communication in Medicine coordinates. Results: The location of sigmoid, small bowel, and bladder D2 cc hot spots was around the endocervix: The mean location of sigmoid hot spot for lateral view was 1.6cm posteriorly and 2.3cm superiorly (Y, 1.6 and Z, 2.3), small bowel was 1.6cm anteriorly and 2.7cm superiorly (Y, -1.6 and Z, 2.7). The mean location of bladder hot spot was 1.6cm anteriorly and 1.6cm superiorly (Y, -1.6 and Z, 1.6). These hot spots were near the plane of Point A (X, 2.0 or -2.0; Y, 0; and Z, 2.0). The mean location of rectal hot spot was 1.6cm posteriorly and 1.9cm inferiorly (Y, 1.6 and Z, -1.9). D2 cc hot spot was affected by uterine wall thickness, uterine tandem position, fibroids, bladder fullness, bowel gas, and vaginal packing. Conclusions: Because of the location of the D2 cc hot spots, larger tumors present a challenge for adequate tumor coverage with a conventional brachytherapy applicator without an interstitial implant. Additionally, anatomic factors were identified which affect the D2 cc hot spot in OARs. © 2014 American Brachytherapy Society.
  • Published In

  • Brachytherapy  Journal
  • Digital Object Identifier (doi)

    Author List

  • Kim RY; Dragovic AF; Whitley AC; Shen S
  • Start Page

  • 203
  • End Page

  • 209
  • Volume

  • 13
  • Issue

  • 2