Contouring guidelines

The following contouring guidelines were provided to the experts drawing the ground truth contours. Consequently, they should form the basis of any system preforming auto-contouring. Please note however, the expert contours, have not be checked by the organisers as conforming to these guidelines - since variation in expert opinion is one of the challenges for clinical systems. To mitigate this variation to some extent, a consensus contour of the expert contours will be used as the reference contour against which plans and contours will be assessed.

Naming convention

The naming will follow TG-263 [1]. The tables below define the structure names to be used. An attempt will be made to allow for some variation in naming following the dictionary-based approach of Schuler et al. [2], but adhering to the convention will ensure successful interpretation.

Structure Notes
Bowel_Bag Participants may add "~" if not whole structure
Bladder
Rectum
Femur_Head_L
Femur_Head_R
Prostate The anatomical prostate used to derive treatment volumes
SeminalVes The full seminal vesicles
Proximal_SeminalVes Assume all patients are intermediate risk according to Salembier et al. [5]
CTV_Prostate Prostate 
CTV_SeminalVes
CTV_LN_Pelvic
CTV_ProstateBed
PTVp_7400 Prostate. Assume no SV involvement
PTVp_7100 Prostate. Assume no SV involvement
PTVp_6000 Prostate + Proximal SV. Equivalent to PTVpsv_6000 in supplementary material to Dearnaley et al. [3]
PTVp_6600 Prostate Bed PTV
PTVn_6000 Nodal planning volume for Prostate + Nodes cases, consisting of PTVn + PTVp_6000
PTVn_5000 Nodal planning volume for ProstateBed + Nodes cases, consisting of PTVn + PTVp_6600

Organ-at-risk definitions

OARs are to be contoured according to Gay et al. [4]

CTV contour definitions

Prostate and Seminal Vesicles should be contoured according to Salembier et al. [5]
ProstateBed should be contoured according to Robin et al. [6]
Pelvic Lymph Nodes should be contoured according to Harris et al. [7]

PTV contour definitions

PTV definitions for Prostate and Prostate+Nodes will follow the PIVOTAL trial. The following is adapted from the supplementary material to Dearnaley et al. [3], noting that the CTV_SeminalVes definition follows [5]. For the prostate bed a PTV margin of 5mm will be used following Poortmans et al. [8] The table below details the PTV regions.

Tumour and Clinical Target Volumes Clinical Target Volume Planning Target Volumes
Prostate and seminal vesicles CTV_Prostate + CTV_SeminalVes
Outline: prostate & seminal vesicles
PTVp_6000
10mm isotropic margin from CTV
Prostate (+ any involved seminal vesicle) CTV_Prostate
Outline: prostate and any involved seminal vesicle
PTVp_7100
10mm margin in all directions except 5mm towards Rectum from CTV
CTV_Prostate
Outline: prostate and any involved seminal vesicle
PTVp_7400
5mm margin in all directions except 0mm towards Rectum from CTV
Prostate Bed PTV CTV_ProstateBed
Outline: prostate bed
PTVp_6600
Margin 5mm in all directions from CTV
Pelvic lymph nodes CTV_LN_Pelvic
Outline: pelvic lymph nodes
PTVn
5mm margin in all directions from CTV
For Prostate + Nodes cases PTVn_6000 = PTVp_6000 + PTVn
For ProstateBed cases PTVn_4600 = PTVp_6600 + PTVn

Full guidelines

Full guidelines including appendix are available to download in pdf format

References

  1. Mayo CS, Moran JM, Bosch W, et al. American Association of Physicists in Medicine Task Group 263: Standardizing Nomenclatures in Radiation Oncology. Int J Radiat Oncol Biol Phys 2018; 100: 1057–66.
  2. Schuler T, Kipritidis J, Eade T, et al. Big Data Readiness in Radiation Oncology: An Efficient Approach for Relabeling Radiation Therapy Structures With Their TG-263 Standard Name in Real-World Data Sets. Adv Radiat Oncol 2019; 4: 191–200.
  3. Dearnaley D, Griffin CL, Lewis R, et al. Toxicity and Patient-Reported Outcomes of a Phase 2 Randomized Trial of Prostate and Pelvic Lymph Node Versus Prostate only Radiotherapy in Advanced Localised Prostate Cancer (PIVOTAL). Int J Radiat Oncol Biol Phys 2019; 103: 605–17.
  4. Gay HA, Barthold HJ, O’Meara E, et al. Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas. Int J Radiat Oncol 2012; 83: e353–62.
  5. Salembier C, Villeirs G, De Bari B, et al. ESTRO ACROP consensus guideline on CT- and MRI-based target volume delineation for primary radiation therapy of localized prostate cancer. Radiother Oncol 2018; 127: 49–61.
  6. Robin S, Jolicoeur M, Palumbo S, et al. Prostate Bed Delineation Guidelines for Postoperative Radiation Therapy: On Behalf Of The Francophone Group of Urological Radiation Therapy. Int J Radiat Oncol Biol Phys 2021; 109: 1243–53.
  7. Harris VA, Staffurth J, Naismith O, et al. Consensus guidelines and contouring atlas for pelvic node delineation in prostate and pelvic node intensity modulated radiation therapy. Int J Radiat Oncol Biol Phys 2015; 92: 874–83.
  8. Poortmans P, Bossi A, Vandeputte K, et al. Guidelines for target volume definition in post-operative radiotherapy for prostate cancer, on behalf of the EORTC Radiation Oncology Group. Radiother Oncol 2007; 84: 121–7.
  9. Hall WA, Paulson E, Davis BJ, et al. NRG Oncology Updated International Consensus Atlas on Pelvic Lymph Node Volumes for Intact and Postoperative Prostate Cancer. Int J Radiat Oncol 2021; 109: 174–85.
  10. McLaughlin PW, Evans C, Feng M, Narayana V. Radiographic and Anatomic Basis for Prostate Contouring Errors and Methods to Improve Prostate Contouring Accuracy. Int J Radiat Oncol 2010; 76: 369–78.