Patterns of local-regional failure after primary intensity modulated radiotherapy for nasopharyngeal carcinoma

Radiation Oncology

Table 3 Details of recurrent patients and their local-regional failures

				Dose–volume histograms statistics to recurrence volume
No.	Stage	Site of relapse	Location of the recurrence volume	Vrecur (cc)	Dmean (Gy)	Dmin (Gy)	Dmax (Gy)	V_95%(%)	Type of relapse^a
1	T4N3b	Local	CTV	13.9	69.9	48.5	75.2	97.9	In-field
		Regional	CTV	2.7	68.9	64.6	71.3	100	In-field
2	T4N1	Local	Marginal to CTV	10.5	70	51.5	77	94.3	marginal
3	T4N0	Local	CTV	32.9	70.9	37.6	75.4	97.7	In-field
4	T3N3b	Local	Marginal to CTV	13.9	62.1	11.8	74.1	74.7	marginal
		Regional	CTV	3.6	67.5	63.9	71.9	100	In-field
5	T2N1	Local	CTV	15.1	67.6	60	71.2	100	In-field
6	T1N0	Local	CTV	10.2	65.1	53.3	71.7	100	In-field
7	T3N3b	Local	CTV	2.2	70	63	76.8	100	In-field
		Regional	Outside CTV	8.4	14.2	11.2	37.7	-	outside
8	T3N1	Local	GTV	10.6	73.5	69.1	76.3	100	In-field
		Regional	CTV	5.5	69.6	65.9	73.6	100	In-field
9	T4N0	Local	GTV	9.3	72	61.8	74	99.2	In-field
10	T3N2	Local	CTV	15.2	71.9	63.3	77.3	100	In-field
11	T4N1	Local	CTV	8	72.1	66	73.8	100	In-field
12	T4N3b	Regional	-	-	-	-	-	-	-
13	T3N2	Regional	CTV	20.6	67.8	51.2	72.6	99.6	In-field
14	T2N1	Regional 1	Outside CTV	3.6	45.3	34.6	56.7	-	outside
		Regional 2	Marginal to CTV	12.6	53.4	20.6	66.7	32.5	marginal
		Regional 3	Outside CTV	2.7	54.2	46.6	61.4	19.1	outside
15	T3N2	Regional	-	-	-	-	-	-	-
16	T3N3b	Regional	CTV	4.2	66.5	61.3	69.3	100	In-field
17	T1N2	Regional	GTV	2.2	70.1	67.9	72.4	100	In-field
18	T3N3b	Regional 1	-	-	-	-	-	-	-
		Regional 2	CTV	22.2	65.6	51.4	73	98.8	In-field

CTV clinical target volume, GTV gross tumor volume; V95%=% of volume of failure receiving at least 95% of prescribed total dose, Vrecur the recurrent tumor volume.
^aIn-field refers to 95% of the recurrence volume receiving more than 95% of the prescribed dose. Marginal refers to 20–95% of the recurrence volume receiving 95% of the prescribed dose. Outside refers to less than 20% of the the recurrence volume receiving 95% of the prescribed dose.

ISSN: 1748-717X