Table 4.

Width, Height and Thickness details for defining and delineating four categories of CTV-T_HR-CT based on CT at diagnosis & Pre BT MR and CT at BT (CT - Pre BT MRI and CT_BT Environment).

Category of BT	Width	Height		Thickness
	Lateral	Superior	Inferior	Anterior	Posterior
IBT	Lateral boundaries of cervix		Lower extent of cervical lip with vaginal applicator as surrogate	Outer surface of the cervix &/or uterus guided by Pre BT MR dimensions	Outer surface of the cervix &/or uterus guided by Pre BT MR dimensions
IIBT	Proximal parametrium defined by clinical/TRUS based NMD’s (if available) and guided by NMD’s on Pre-BT MR	Lower two thirds of utero-cervical dimensions	Include appropriate length of vaginal wall defined by clinical examination and with /without guidance of markers implanted and the Pre BT MR findings with few mm longitudinal and upto 2 cm circumferential safety margins
				To utilize TRUS based distances (if available)	To utilize TRUS based distances (if available)
IIIBT	Distal parametrium defined by clinical/TRUS based NMD’s (if available) and guided by NMD’s on Pre-BT MR$
IVBT	Proximal /distal parametrium/Up to lateral pelvic wall defined by clinical/TRUS based NMD’s (if available) and guided by NMD’s on Pre-BT MR.		Length and circumference of vagina should not exceed vaginal disease at diagnosis	In addition to outer surface of the cervix &/or uterus to include the bladder wall/mucosae involved with 2 cm margins at least guided by Pre BT MR findings To utilize TRUS based distances (if available)	In addition to outer surface of the cervix &/or uterus to include the rectal wall/mucosae involved with 2 cm margins at least guided by Pre BT MR findings To utilize TRUS based distances (if available)