AIM: To investigate biological prevention with flavonoids the recurrence risk of neoplasia was studied in patients with resected colorectal cancer and after adenoma polypectomy. METHODS: Eighty-seven patients, 36 patients with resected colon cancer and 51 patients after polypectomy, were divided into 2 groups: one group was treated with a flavonoid mixture (daily standard dose 20 mg apigenin and 20 mg epigallocathechin-gallat, n = 31) and compared with a matched control group (n = 56). Both groups were observed for 3-4 years by surveillance colonoscopy and by questionnaire. RESULTS: Of 87 patients enrolled in this study, 36 had resected colon cancer and 29 of these patients had surveillance colonoscopy. Among the flavonoid-treated patients with resected colon cancer (n = 14), there was no cancer recurrence and one adenoma developed. In contrast the cancer recurrence rate of the 15 matched untreated controls was 20% (3 of 15) and adenomas evolved in 4 of those patients (27%). The combined recurrence rate for neoplasia was 7% (1 of 14) in the treated patients and 47% (7 of 15) in the controls (P = 0.027). CONCLUSION: Sustained long-term treatment with a flavonoid mixture could reduce the recurrence rate of colon neoplasia in patients with resected colon cancer. AIM: To investigate biological prevention with flavonoids the recurrence risk of neoplasia was studied in patients with resected colorectal cancer and after adenoma polypectomy. METHODS: Eighty-seven patients, 36 patients with resected colon cancer and 51 patients after polypectomy, were divided into 2 groups : one group was treated with a flavonoid mixture (daily standard dose 20 mg apigenin and 20 mg epigallocathechin-gallat, n = 31) and compared with a matched control group (n = 56). Both groups were observed for 3-4 years by surveillance of the colonoscopy and by questionnaire. RESULTS: Of 87 patients enrolled in this study, 36 had resected colon cancer and 29 of these patients had surveillance colon cancer. Among the flavonoid-treated patients with resected colon cancer (n = 14), there was no cancer In contrast the cancer recurrence rate of the 15 matched untreated controls was 20% (3 of 15) and adenomas evolved in 4 of those patients (27%). The combin The recur recurrence rate for neoplasia was 7% (1 of 14) in the treated patients and 47% (7 of 15) in the controls (P = 0.027). CONCLUSION: Sustained long-term treatment with a flavonoid mixture could reduce the recurrence rate of colon neoplasia in patients with resected colon cancer.