Table 3.

Initial characteristics and analysis of the patients who developed a local and/or regional recurrence.

	Patients	TNM	Age at diagnosis	Location	Nodal Extension	Margin	PNI	Flap	Chemotherapy	Surgery-RT interval (days)	Prescribed Dose (Gy)	Treatment Time (days)	Time to recurrence (months)	Recurrence anatomical description	Recurrence analysis
Local T recurrence only	1	T4aN2aM0	52	Mobile tongue	ENE +	R1	Yes	Yes	Yes	39	66	46	9.2	Tongue/tongue flap junction	Infield.
	2	T3N2cM0	78	Base of tongue	ENE +	R1	Yes	Yes	No	41	66	50	7.1	Base of Tongue	Infield.
	3	T4aN0M0	50	Mandible	N0	R1	Yes	No	No	53	66	50	20.7	Homolateral mandible	Infield.
	4	T4aN2cM0	54	Floor of mouth	ENE +	R1	Yes	Yes	Yes	49	66	49	15.7	Fibula flap region	Infield
	5	T3N1M0	77	Mobile tongue	ENE -	R0	No	No	No	47	66	45	16.4	Mobile tongue	Infield.
	6	T3N1M0	59	Floor of mouth	ENE -	R1	Yes	No	Yes	48	66	46	4.2	Mobile tongue/ floor of mouth junction	Infield
	7	T4N1M0	72	Retromolar area	ENE +	R<5 mm	Yes	Yes	No	51	66	48	12.3	Digastric muscle	Outfield
	8	T4aN0M0	62	Floor of mouth	N0	R<5 mm	Yes	Yes	No	48	60	38	2.7	Fibula flap region	Marginal
	9	T3N1M0	60	Upper lip	ENE +	R0	Yes	Yes	Yes	83	60	48	3.1	Upper jaw	Infield.
	10	T3N0M0	56	Base of tongue	N0	R1	Yes	Yes	Yes	38	66	47	29.1	Macroscopic PNI along the lingual nerve	Infield
	11	T1N0M0	65	Tonsil	N0	R<5 mm	Yes	No	No	39	66	45	4.8	Mobile Tongue	Marginal
	12	T3N0M0	79	Hard Palate	N0	R1	Yes	No	No	41	66	44	6.6	Hard Palate	Marginal
Both local and regional recurrence	13	T4aN2cM0	42	Floor of mouth	ENE +	R<5 mm	Yes	Yes	Yes	48	60	38	4.7	T: Tongue / flap junction	T: Infield.
	14	T3N0M0	77	Cheek	N0	R1	No	Yes	No	35	66	45	27.8	T: Mandible	T: Infield
	15	T4aN2bM0	65	Retromolar area	ENE -	R1	No	Yes	Yes	41	66	43	11	T: Infratemporal fossa	T: Outfield
	16	T4aN2cM0	26	Mobile tongue	ENE +	R1	Yes	Yes	Yes	35	66	45	1.4	T: Base of tongue	T: Infield.
	17	T4N2cM0	20	Floor of mouth	ENE +	R<5 mm	Yes	Yes	Yes	41	60	45	3	T: Oropharynx Hypopharynx	T: Marginal
Regional N recurrence only	18	T4aN2cM0	53	Mobile Tongue	ENE + III controlateral	R1	Yes	Yes	Yes	42	66	48	4	IVa controlateral	Infield (54Gy)
	19	T3N0M0	51	Retromolar area	N0	R0		Yes	No	49	60	50	3.8	Ib homolateral	Infield (54Gy)
	20	T2N2cM0	54	Oropharynx	ENE + IIB homolateral	R1		No	Yes	42	66	51	39	VIIA homolateral	Infield (54Gy)
	21	T3N2bM0	80	Mobile tongue	ENE + IIA homolateral	R<5mm		No	No	44	66	47	4	IV homolateral	Infield (54Gy)
	22	T1N2aM0	74	Left Tonsil	ENE + IIB homolateral	R0	No	No	No	43	66	44	12	VIIA homolateral	Infield (60Gy)
	23	T4aN3bM0	79	Hard Palate	ENE + IIA homolateral	R1	Yes	No	No	48	60	39	8.5	II A IIB III contralateral (unilateral irradiation)	Outfield
	24	T1N2cM0	49	Mobile tongue	ENE + IIA bilateral	R1		No	Yes	44	66	48	4	IB homolateral	Infield (60Gy)
	25	T2N2bM0	56	Floor of mouth	ENE + IIA homolateral	R<5 mm	Yes	Yes	Yes	43	66	50	9	IIB-IV-V homolateral	Infield (60Gy)
	26	T4N1M0	80	Floor of mouth	ENE – IIB homolateral	R1	Yes	Yes	No	43	60	41	4	IIB homolateral	Infield (60Gy)

R1= positive margin, R<5mm=close margin <5mm, R0=negative margin, ENE +, extranodal extension; ENE -, positive node without extranodal extension; N - , no positive node; Surgery – RT interval, interval between surgery and the first day of radiotherapy.