Table 2

Risk of adenomas; evidence of substantial effect in active arm

Follow-up colonoscopy 2 to 39 mo after beginning treatment (n = 267)Follow-up colonoscopy 33 to 36 mo after beginning treatment (n = 204)
Placebo (n = 129)DFMO/sulindac (n = 138)Placebo (n = 97)DFMO/sulindac (n = 107)
Detection of any adenoma
 Cumulative incidence of adenomas detected at end of the treatment (%)53 (41.1)17 (12.3)42 (43.3)12 (11.2)
 Risk ratio* (95% CI)0.30 (0.18-0.49)0.26 (0.15-0.46)
P<0.001<0.001
Detection of advanced adenomas
 Cumulative incidence of advance adenomas detected at end of the treatment (%)11 (8.5)1 (0.7)9 (9.3)1 (0.9)
 Risk ratio* (95% CI)0.085 (0.011-0.65)0.10 (0.013-0.78)
P0.0010.004
Detection of advanced adenomas with size ≥1 cm
 Cumulative incidence of advanced adenomas with size ≥1 cm detected at end of the treatment (%)9 (7.0)1 (0.7)7 (7.2)1 (0.9)
 Risk ratio* (95% CI)0.10 (0.013-0.81)0.13 (0.016-1.03)
P0.0040.02
Detection of multiple adenomas (>1)
 Patients with >1 adenoma, incidence (%)17 (13.2)1 (0.7)15 (15.5)1 (0.9)
 Risk ratio* (95% CI)0.055 (0.0074-0.41)0.060 (0.0081-0.45)
P<0.001<0.001
Sensitivity analysis imputing adenoma for patients without an end-point determination
 Cumulative incidence of adenomas detected at end of the treatment (%)76/184 (41.3)39/191 (20.4)
 Risk ratio* (95% CI)0.49 (0.36-0.69)
P<0.001
  • *Relative risk estimation by log-binomial regression. Likelihood ratio test P values are reported.

  • Advanced adenomas in the placebo group included tubulovillous (3), intramucosal carcinoma (2), size ≥1 cm (6), and one serrated adenoma with high-grade dysplasia; the one advanced adenoma in the treatment group was an adenoma >1 cm.

  • Sensitivity analysis imputing adenoma for all patients without an end-of-study colonoscopy at the placebo rate of recurrence.