Table 4.

Risk of skin cancer for anti-TNF therapy in patients with RA without previous history of skin cancer

	BCC					SCC
	nbDMARD	Anti-TNF	Etanercept	Infliximab	Adalimumab	nbDMARD	Anti-TNF
Number ever exposed to drug during follow-up	3523	11 704	5086	3663	5035	3523	11 704
Exposure time (years)	9342	43 798	19 108	11 700	12 991	9342	43 798
Median exposure time per subject (years)	2.65	4.01	3.70	2.70	2.05	2.65	4.01
Patients with cancer	34	121	47	45	29	4	19
Cancers	38	150	57	59	34	4	23
Incident rate/100 000 patient-years (95% CI)	407 (288 to 558)	342 (290 to 402)	298 (226 to 387)	504 (384 to 650)	262 (181 to 366)	43 (12 to 110)	53 (33 to 79)
Unadjusted HR (95% CI)	Ref	0.84 (0.58 to 1.20)	0.71 (0.47 to 1.08)	1.25 (0.83 to 1.89)	0.64 (0.40 to 1.02)	Ref	0.93 (0.32 to 2.76)
Age and gender HR (95% CI)	Ref	1.20 (0.83 to 1.73)	1.07 (0.70 to 1.63)	1.73 (1.14 to 2.62)	0.89 (0.56 to 1.42)	Ref	1.79 (0.59 to 5.41)
aHR (95% CI)	Ref	0.95 (0.53 to 1.71)	0.80 (0.44 to 1.47)	1.47 (0.76 to 2.85)	0.73 (0.37 to 1.46)	Ref	1.16 (0.35 to 3.84)
First cancer per subject incident rate/100 000 patient-years (95% CI)	364 (252 to 509)	276 (229 to 330)	246 (181 to 328)	376 (273 to 505)	231 (156 to 330)
First cancer per subject aHR (95% CI)	Ref	0.81 (0.45 to 1.48)	0.69 (0.37 to 1.29)	1.15 (0.60 to 2.21)	0.68 (0.33 to 1.38)
Excluding first year of follow-up aHR (95% CI)	Ref	1.18 (0.60 to 2.32)	1.05 (0.52 to 2.14)	1.70 (0.81 to 3.58)	0.91 (0.41 to 2.01)
On drug analysis aHR (95% CI)	Ref	0.88 (0.48 to 1.60)	0.68 (0.36 to 1.29)	1.24 (0.63 to 2.46)	0.68 (0.32 to 1.42)	Ref	0.96 (0.28 to 3.32)

aHR, hazard ratio adjusted for inverse probability of treatment weighting; BCC,basal cell carcinoma; nbDMARD, non-biological disease-modifying antirheumatic drug; RA, rheumatoid arthritis; Ref, referent; SCC, squamous cell carcinoma; TNF, tumour necrosis factor.