Table 3.
Incidence of gastric carcinoma
| Groups | Age colonized | Duration of colonization | Age sacrificed | No. of animals | Carcinoma | ||
|---|---|---|---|---|---|---|---|
| Dif. | Undif. | Incidence (%) | |||||
| A Hp 20 w + MNU | 7 w | 70 w | 77 w | 20 | 12 | 1 | 13 (65.0)* |
| a1 before MNU treatment | 7 w | 20 w | 27 w | 6 | 0 | 0 | 0 |
| B Hp 8 w + MNU | 19 w | 58 w | 77 w | 10 | 2 | 0 | 2 (20.0) |
| b1 before MNU treatment | 19 w | 8 w | 27 w | 7 | 0 | 0 | 0 |
| C Hp 2 w + MNU | 25 w | 52 w | 77 w | 13 | 2 | 1 | 3 (23.1) |
| c1 before MNU treatment | 25 w | 2 w | 27 w | 7 | 0 | 0 | 0 |
| D MNU | (‐) | (‐) | 77 w | 16 | 0 | 0 | 0 |
| E Hp 70 w | 7 w | 70 w | 77 w | 5 | 0 | 0 | 0 |
| F Hp 58 w | 19 w | 58 w | 77 w | 5 | 0 | 0 | 0 |
| G Hp 52 w | 25 w | 52 w | 77 w | 5 | 0 | 0 | 0 |
| H Control | (‐) | (‐) | 77 w | 6 | 0 | 0 | 0 |
*
P < 0.05 between groups A, B and C, P < 0.05 to group B and group C, P < 0.001 to group D, by Fisher"s exact test. Hp, H. pylori infection (i.g.); Dif, differentiated adenocarcinoma; Undif, undifferentiated adenocarcinoma. MNU, N‐methyl‐N‐nitorosourea.