Table 1.

Sample specification

Sample	Breed	Age	Clinical Description	Histological Diagnosis
1	Pony	18	preputial tumoural lesion, 5 cm diameter	SCC
2	German riding horse	20	multiple depigmented wart-like lesions glans penis	SCC
3	Haflinger	16	generalized hyperplasia of the penis with tumoural changes on the glans penis, 10 cm diameter	SCC
4	Welsh Pony	22	generalized hyperplasia of the penis with tumoural changes on the glans penis, 5 cm diameter	SCC early
5	Icelandic horse	17	generalized hyperplasia and ulcerative lesions on the penis shaft	SCC early
6	Icelandic horse	22	multiple depigmented plaques glans penis and penis shaft with wart-like lesion on glans penis	CIS
7	Bavarian Warmblood	16	multiple depigmented plaques and tumoural lesion penis	CIS
8	Icelandic horse	16	multiple wart-like lesions penis shaft	CIS
9	n.a.	13	wart-like lesion penis shaft	Papilloma
10	Icelandic horse	20	tumoural lesion penis 2 cm diameter	Papilloma
11	Lusitano	14	multiple large wart-like lesions	Papilloma
12	Shetland Pony	20	multiple large wart-like lesions penis	Papilloma
13	Icelandic horse	17	generalized hyperplasia and wart-like lesions	Papilloma
14	n.a.	8	depigmented plaques penis	Hyperplasia
15	Welsh Pony	13	depigmented plaques penis	Hyperplasia
16	Lusitano	15	depigmented plaques penis	Hyperplasia
17	Freiberger	13	generalized hyperplasia and ulcerative lesions penis	Hyperplasia
18	Irish Warmblood	14	plaque-like lesion penis shaft	Hyperplasia
19	Icelandic horse	22	plaque-like lesions penis shaft and glans	Hyperplasia

n.a. not available, clinical description: the parts of the lesions, which were further assessed histologically in this study, are marked in bold