Table 2.
Types of canine mammary columnar cell lesions and associated neoplastic alterations.
| Tumor types(**) | CCC(%) | CCH(%) | FEA(%) | Total(%) |
| invasive carcinomas | 12 (30.7) | - | 5 (19.2) | 19 (28.4) |
| carcinoma in benign tumor | 6 (15.3) | 2 (100) | 3 (11.5) | |
| solid carcinoma | 2 (5.1) | - | 2 (7.2) | |
| tubulopapillary carcinoma | 4 (10.3) | - | - | |
| ductal carcinoma in situ | 7 (17.9) | - | 13 (50.0)(*) | 20 (29.8) |
| benign tumors | 18 (46.1)(*) | 3 (11.5) | 21 (31.4) | |
| simple adenoma | 3 (7.6) | - | - | |
| duct papilloma | 7 (17.9) | - | 1 (3.8) | |
| benign mixed tumor | 8 (20.6) | - | 2 (7.7) | |
| without tumor | 2 (5.1) | - | 5 (19.2) | 7 (10.4) |
| Total | 39 (100) | 2 (100) | 26 (100) | 67 (100) |
(*)Flat epithelial atypia presence is often associated with in situ carcinomas and columnar cell lesion without atypia are more frequent in benign tumors (P < 0,05).
(**)Misdorp,1999. International Histological Classification of Tumors of Domestic Animals.
CCC: columnar cell change without atypia; CCH: columnar cell hyperplasia without atypia; FEA: flat epithelial atypia