1. 11 RTOG Sarcoma Working Group Consensus on The GTV and CTV For Preoperative Radiotherapy of Large High Grade Extremity Soft Tissue Sarcoma Dian Wang, MD., Ph.D. Medical College of Wisconsin RTOG Extremity Soft Tissue Sarcoma Atlas

2. 22 Definition of GTV and CTV Gross Target Volume (GTV): Gross tumor defined by MRI T1 plus contrast images (MRI with contrast is required). Fusion of MRI and CT is recommended to delineate the GTV for radiotherapy planning. Intravenous contrast is recommended, particularly for upper extremity lesions, where there is a greater rotational mobility and positioning fidelity between the diagnostic MRI and the planning CT may be more difficult to achieveGross Target Volume (GTV): Gross tumor defined by MRI T1 plus contrast images (MRI with contrast is required). Fusion of MRI and CT is recommended to delineate the GTV for radiotherapy planning. Intravenous contrast is recommended, particularly for upper extremity lesions, where there is a greater rotational mobility and positioning fidelity between the diagnostic MRI and the planning CT may be more difficult to achieve Clinical Target Volume (CTV) for intermediate-to-high grade sarcoma ≥ 5 cm: Include gross tumor and clinical microscopic margins. Typically CTV = GTV plus 3 cm margins in the longitudinal (proximal and distal) directions. If this causes the field to extend beyond the compartment, the field can be shortened to include the end of a compartment. The radial margin from the lesion should be 1.5 cm including any portion of the tumor not confined by an intact fascial barrier, bone or skin surface. The suspicious edema defined on MRI T2 images is often included within the above margins. However, clinical judgment is required to make sure if the above margins need to be extended to cover the T2 edema defined on MRI T2 images. For example, the extensive T2 edema may be excluded if clinical judgment suggests that the risk of the edema harboring sarcoma many cm beyond the GTV is low or if extending the radiation field to include all of the edema would cause excessive toxicity.Clinical Target Volume (CTV) for intermediate-to-high grade sarcoma ≥ 5 cm: Include gross tumor and clinical microscopic margins. Typically CTV = GTV plus 3 cm margins in the longitudinal (proximal and distal) directions. If this causes the field to extend beyond the compartment, the field can be shortened to include the end of a compartment. The radial margin from the lesion should be 1.5 cm including any portion of the tumor not confined by an intact fascial barrier, bone or skin surface. The suspicious edema defined on MRI T2 images is often included within the above margins. However, clinical judgment is required to make sure if the above margins need to be extended to cover the T2 edema defined on MRI T2 images. For example, the extensive T2 edema may be excluded if clinical judgment suggests that the risk of the edema harboring sarcoma many cm beyond the GTV is low or if extending the radiation field to include all of the edema would cause excessive toxicity.

3. 33 Example Case 55-year-old male with a large high-grade round cell liposarcoma in right distal thigh. Clinical stage (AJCC 7 th edition) III T2bN0M0G3.55-year-old male with a large high-grade round cell liposarcoma in right distal thigh. Clinical stage (AJCC 7 th edition) III T2bN0M0G3. –The MRI of right distal thigh showed a large well circumscribed heterogeneous, multiloculated mass located within the posterior thigh. –The tumor measured 14.8 cm in craniocaudal dimension, 7.8 cm in AP dimension, and 11.3 cm in maximal medial-lateral dimension. Simulation CT images were fused with those from the diagnostic thigh MRISimulation CT images were fused with those from the diagnostic thigh MRI

4. 44 Consensus Contours The consensus contours for the GTV and CTV were generated based on the modification of the 95% agreement contours by RTOG Sarcoma Working Group Radiation OncologistsThe consensus contours for the GTV and CTV were generated based on the modification of the 95% agreement contours by RTOG Sarcoma Working Group Radiation Oncologists –Dian Wang, Walter Bosch, David Roberge, Steven E. Finkelstein, Ivy Petersen, Michael Haddock, Yen-Lin E. Chen, Naoyuki G. Saito, David G. Kirsch, Ying J. Hitchcock, Aaron H. Wolfson, Thomas F. DeLaney. RTOG Sarcoma Radiation Oncologists Reach Consensus on Gross Tumor Volume (GTV) and Clinical Target Volume (CTV) on Computed Tomographic Images for Preoperative Radiotherapy of Primary Soft Tissue Sarcoma of Extremity in RTOG Studies. IJROBP June 2011

5. 55

6. 66 ←CTV

7. 77

8. 88

9. 99

10. 10 ←CTV

11. 11 ←CTV

12. 12 ←CTV

13. 13 ←CTV

14. 14 ←CTV

15. 15 ←CTV

16. 16 ←CTV

17. 17 ←CTV

18. 18 GTV→ ←CTV

19. 19 GTV→ ←CTV

20. 20 GTV→ ←CTV

21. 21 GTV→ ←CTV

22. 22 GTV→ ←CTV

23. 23 GTV→ ←CTV

24. 24 GTV→ ←CTV

25. 25 GTV→ ←CTV

26. 26 GTV→ ←CTV

27. 27 GTV→ ←CTV

28. 28 GTV→ ←CTV

29. 29 GTV→ ←CTV

30. 30 GTV→ ←CTV

31. 31 GTV→ ←CTV

32. 32 GTV→ ←CTV

33. 33 GTV→ ←CTV

34. 34 GTV→ ←CTV

35. 35 GTV→ ←CTV

36. 36 GTV→ ←CTV

37. 37 GTV→ ←CTV

38. 38 GTV→ ←CTV

39. 39 GTV→ ←CTV

40. 40 GTV→ ←CTV

41. 41 GTV→ ←CTV

42. 42 GTV→ ←CTV

43. 43 GTV→ ←CTV

44. 44 GTV→ ←CTV

45. 45 GTV→ ←CTV

46. 46 GTV→ ←CTV

47. 47 GTV→ ←CTV

48. 48 GTV→ ←CTV

49. 49 GTV→ ←CTV

50. 50 GTV→ ←CTV

51. 51 GTV→ ←CTV

52. 52 GTV→ ←CTV

53. 53 GTV→ ←CTV

54. 54 GTV→ ←CTV

55. 55 GTV→ ←CTV

56. 56 GTV→ ←CTV

57. 57 GTV→ ←CTV

58. 58 GTV→ ←CTV

59. 59 GTV→ ←CTV

60. 60 GTV→ ←CTV

61. 61 GTV→ ←CTV

62. 62 GTV→ ←CTV

63. 63 GTV→ ←CTV

64. 64 GTV→ ←CTV

65. 65 GTV→ ←CTV

66. 66 GTV→ ←CTV

67. 67 GTV→ ←CTV

68. 68 GTV→ ←CTV

69. 69 GTV→ ←CTV

70. 70 GTV→ ←CTV

71. 71 GTV→ ←CTV

72. 72 GTV→ ←CTV

73. 73 GTV→ ←CTV

74. 74 GTV→ ←CTV

75. 75 GTV→ ←CTV

76. 76 GTV→ ←CTV

77. 77 GTV→ ←CTV

78. 78 GTV→ ←CTV

79. 79 GTV→ ←CTV

80. 80 ←CTV

81. 81 ←CTV

82. 82 ←CTV

83. 83 ←CTV

84. 84 ←CTV

85. 85 ←CTV

86. 86 ←CTV

87. 87 ←CTV

88. 88 ←CTV

89. 89 ←CTV

90. 90 ←CTV

91. 91