Table 2. Tp53 mutation and HPV DNA detection in skin lesions, perilesions and non-lesional control samples from subjects with and without SCC.

	SCC subjects		Control subjects		P1 (les vs. peri)		P2 (les vs. sun)		P3 (peri vs. sun)
	Lesional tissue (n = 55)	Perilesion tissue (n = 55)	Non-lesional sun-exposed tissue (n = 41)	Non-lesional sun-protected tissue (n = 41)
Tp53 Mutations
Any	18 (33%)	9 (16%)*	1 (2%)**	2 (5%)	0.03	<0.001		0.04
Single	14 (25%)	8 (15%)	1 (2%)	0 (0%)
Multiple	4 (7%)	1 (2%)	0 (0%)	2 (5%)
Non-synonymous coding mutations
Any	17 (31%)	8 (15%)*	0 (0%)**	2 (5%)	0.03	<0.001		0.01
Single	14 (25%)	7 (13%)	0 (0%)	1 (2%)
Multiple	3 (5%)	1 (2%)	0 (0%)	1 (2%)
UV-damage C→T or CC→TT transition mutations
Any	13 (24%)	7 (13%)	0 (0%)**	2 (5%)	0.11	<0.001		0.02
Single	12 (22%)	6 (11%)	0 (0%)	1 (2%)
Multiple	1 (2%)	1 (2%)	0 (0%)	1 (2%)
“Hotspot” Mutations ^
Any	11 (20%)	4 (7%)	0 (0%)**	0 (0%)	0.05	0.002		0.13
Single	10 (18%)	4 (7%)	0 (0%)	0 (0%)
Multiple	1 (2%)	0 (0%)	0 (0%)	0 (0%)
HPV DNA	35/53 (66%)	29/53 (55%)	24/40 (60%)	21/41 (51%)	0.13	0.55		0.61
Beta 2 HPV Species	4/20 (20%)	4/20 (20%)	17/40 (43%)	14/41 (34%)	1.00	0.15		0.15

^*p-value<0.05 for cases compared to perilesions (McNemar’s Test).

^**p-value<0.05 for cases compared to sun-exposed controls (Chi-Square test).

^{^}Hotspots include Arg248Trp, Arg196Stop, and His179Stop.