Risk prediction model for cutaneous squamous cell carcinoma in adult cardiac allograft recipients

Table 1 Patient characteristics and predictive variables

	Total (n = 23736)	Derivation group (n = 18989)	Validation group (n = 4747)	P value for derivation vs validation groups	cSCC positive (n = 1827)	cSCC negative (n = 21909)	P value for cSCC positive vs cSCC negative
Age	52.1 (12.6)1	52.1 (12.6)1	52.3 (12.6)1	0.293	59.1 (7.76)1	51.6 (12.7)1	< 0.001
Female	24.5	24.7	23.7	0.159	9.58	25.8	< 0.001
HLA mismatch level	4.67 (1.02)1	4.67 (1.02)1	4.68 (1.01)1	0.966	4.59 (1.05)1	4.68 (1.01)1	< 0.001
PRA against Class I antigens	5.36 (16.3)1	5.41 (16.4)1	5.16 (15.6)1	0.960	3.61 (13.2)1	5.51 (16.5)1	< 0.001
PRA against Class II antigens	3.95 (14.3)1	3.98 (14.4)1	3.83 (14.0)1	0.404	2.85 (12.2)1	4.04 (14.5)1	0.003
Race
White	71.4	71.4	71.6	0.716	97.0	69.3	< 0.001
Black	17.6	17.6	17.5	0.906	0.712	19.0	< 0.001
Hispanic	7.26	7.26	7.27	0.989	1.81	7.72	< 0.001
Other	3.70	3.74	3.54	0.514	0.493	3.97	< 0.001
Diagnosis
Dilated myopathy	82.1	82.1	82.0	0.884	81.5	82.1	0.515
Restrictive myopathy	2.22	2.27	2.00	0.261	2.24	2.21	0.932
Heart re-transplant	2.63	2.58	2.84	0.301	2.68	2.62	0.883
Coronary artery disease	4.47	4.43	4.61	0.582	6.51	4.30	< 0.001
Hypertrophic myopathy	1.92	1.90	2.00	0.636	1.70	1.94	0.475
Valvular heart disease	2.01	2.10	1.69	0.0716	2.35	1.99	0.282
Congenital heart defect	2.46	2.48	2.42	0.835	0.985	2.59	< 0.001
Other	2.23	2.18	2.44	0.272	2.03	2.25	0.532
Donor cancer history
No	98.1	98.1	98.0	0.566	98	98.1	0.764
Yes	1.60	1.56	1.73	0.422	1.81	1.58	0.457
Unknown	0.282	0.29	0.253	0.669	0.164	0.292	0.322
Malignancy at listing
No	92.7	92.8	92.5	0.476	90.3	92.9	< 0.001
Yes	5.83	5.80	5.94	0.708	7.72	5.67	< 0.001
Unknown	1.45	1.42	1.58	0.416	1.97	1.41	0.055
Malignancy at transplant
No	98.1	98.1	97.8	0.15	97.4	98.1	0.039
Yes	0.421	0.416	0.442	0.802	0.712	0.397	0.046
Unknown	1.51	1.45	1.75	0.136	1.86	1.48	0.204
Donor skin cancer history
No	97.4	97.4	97.2	0.571	97.6	97.3	0.518
Yes	0.139	0.147	0.105	0.486	0.164	0.137	0.764
Unknown	2.50	2.46	2.65	0.454	2.24	2.52	0.462
Patient status at transplant
Status 1A	46.4	46.6	45.5	0.213	38.2	47.0	< 0.001
Status 1B	37.6	37.4	38.3	0.268	40.6	37.3	0.006
Status 2	16.0	16.0	16.2	0.817	21.2	15.6	< 0.001
Induction with thymoglobulin	14.6	14.7	14.1	0.335	14.4	14.6	0.819
Induction with ATGAM	5.02	5.11	4.66	0.201	5.15	5.01	0.795
Induction with OKT3	2.32	2.29	2.44	0.517	5.42	2.06	< 0.001
Induction with daclizumab	8.30	8.43	7.77	0.142	12.2	7.98	< 0.001
Induction with basiliximab	17.5	17.4	18.0	0.321	12.6	17.9	< 0.001
Induction with alemtuzumab	1.56	1.56	1.81	0.116	1.48	1.57	0.771

¹Continuous variables are expressed as mean (SD). The rest of the values are categorical variables expressed as percentages. cSCC: Cutaneous squamous cell carcinoma; HLA: Human leukocyte antigen; PRA: Panel-reactive antibody.