AIM: To determine whether folic acid supplementation will reduce the recurrence of colorectal adenomas, the precursors of colorectal cancer, we performed a double-blind placebo-controlled trial in patients with adenom...AIM: To determine whether folic acid supplementation will reduce the recurrence of colorectal adenomas, the precursors of colorectal cancer, we performed a double-blind placebo-controlled trial in patients with adenomatous polyps. METHODS: In the current double-blind, placebo-controlled trial at this VA Medical Center, patients with colorectal adenomas were randomly assigned to receive either a daily 5 mg dose of folic acid or a matched identical placebo for 3 years. All polyps were removed at baseline colonoscopy and each patient had a follow up colonoscopy at 3 years. The primary endpoint was a reduction in the number of recurrent adenomas at 3 years. RESULTS: Of 137 subjects, who were eligible after confirmation of polyp histology and run-in period to conform compliance, 94 completed the study; 49 in folic acid group and 45 in placebo group. Recurrence of adenomas at 3-year was compared between the two groups. The mean number of recurrent polyps at 3-year was 0.36 (SD, 0.69) for folic acid treated patients compared to 0.82 (SD, 1.17) for placebo treated subjects, resulting in a 3-fold increase in polyp recurrence in the placebo group. Patients below 70 years of age and those with left-sided colonicadenomas or advanced adenomas responded better to folic acid supplementation. CONCLUSION: High dose folic acid supplementation is associated with a signif icant reduction in the recurrence of colonic adenomas suggesting that folic acid may be an effective chemopreventive agent for colorectal neoplasia.展开更多
AIM:To present a critical discussion of the efficacy of the faecal pyruvate kinase isoenzyme type M2(faecal M2-PK) test for colorectal cancer(CRC) screening based on the currently available studies.METHODS:A literatur...AIM:To present a critical discussion of the efficacy of the faecal pyruvate kinase isoenzyme type M2(faecal M2-PK) test for colorectal cancer(CRC) screening based on the currently available studies.METHODS:A literature search in PubMed and Embase was conducted using the following search terms:fecal Tumor M2-PK,faecal Tumour M2-PK,fecal M2-PK,faecal M2-PK,fecal pyruvate kinase,faecal pyruvate kinase,pyruvate kinase stool and M2-PK stool.RESULTS:Stool samples from 704 patients with CRC and from 11 412 healthy subjects have been investigated for faecal M2-PK concentrations in seventeen independent studies.The mean faecal M2-PK sensitivity was 80.3%;the specificity was 95.2%.Four studies compared faecal M2-PK head-to-head with guaiacbased faecal occult blood test(gFOBT).Faecal M2PK demonstrated a sensitivity of 81.1%,whereas the gFOBT detected only 36.9% of the CRCs.Eight independent studies investigated the sensitivity of faecal M2-PK for adenoma(n = 554),with the following sensitivities:adenoma < 1 cm in diameter:25%;adenoma > 1 cm:44%;adenoma of unspecified diameter:51%.In a direct comparison with gFOBT of adenoma > 1 cm in diameter,47% tested positive with the faecal M2-PK test,whereas the gFOBT detected only 27%.CONCLUSION:We recommend faecal M2-PK as a routine test for CRC screening.Faecal M2-PK closes a gap in clinical practice because it detects bleeding and nonbleeding tumors and adenoma with high sensitivity and specificity.展开更多
文摘AIM: To determine whether folic acid supplementation will reduce the recurrence of colorectal adenomas, the precursors of colorectal cancer, we performed a double-blind placebo-controlled trial in patients with adenomatous polyps. METHODS: In the current double-blind, placebo-controlled trial at this VA Medical Center, patients with colorectal adenomas were randomly assigned to receive either a daily 5 mg dose of folic acid or a matched identical placebo for 3 years. All polyps were removed at baseline colonoscopy and each patient had a follow up colonoscopy at 3 years. The primary endpoint was a reduction in the number of recurrent adenomas at 3 years. RESULTS: Of 137 subjects, who were eligible after confirmation of polyp histology and run-in period to conform compliance, 94 completed the study; 49 in folic acid group and 45 in placebo group. Recurrence of adenomas at 3-year was compared between the two groups. The mean number of recurrent polyps at 3-year was 0.36 (SD, 0.69) for folic acid treated patients compared to 0.82 (SD, 1.17) for placebo treated subjects, resulting in a 3-fold increase in polyp recurrence in the placebo group. Patients below 70 years of age and those with left-sided colonicadenomas or advanced adenomas responded better to folic acid supplementation. CONCLUSION: High dose folic acid supplementation is associated with a signif icant reduction in the recurrence of colonic adenomas suggesting that folic acid may be an effective chemopreventive agent for colorectal neoplasia.
文摘AIM:To present a critical discussion of the efficacy of the faecal pyruvate kinase isoenzyme type M2(faecal M2-PK) test for colorectal cancer(CRC) screening based on the currently available studies.METHODS:A literature search in PubMed and Embase was conducted using the following search terms:fecal Tumor M2-PK,faecal Tumour M2-PK,fecal M2-PK,faecal M2-PK,fecal pyruvate kinase,faecal pyruvate kinase,pyruvate kinase stool and M2-PK stool.RESULTS:Stool samples from 704 patients with CRC and from 11 412 healthy subjects have been investigated for faecal M2-PK concentrations in seventeen independent studies.The mean faecal M2-PK sensitivity was 80.3%;the specificity was 95.2%.Four studies compared faecal M2-PK head-to-head with guaiacbased faecal occult blood test(gFOBT).Faecal M2PK demonstrated a sensitivity of 81.1%,whereas the gFOBT detected only 36.9% of the CRCs.Eight independent studies investigated the sensitivity of faecal M2-PK for adenoma(n = 554),with the following sensitivities:adenoma < 1 cm in diameter:25%;adenoma > 1 cm:44%;adenoma of unspecified diameter:51%.In a direct comparison with gFOBT of adenoma > 1 cm in diameter,47% tested positive with the faecal M2-PK test,whereas the gFOBT detected only 27%.CONCLUSION:We recommend faecal M2-PK as a routine test for CRC screening.Faecal M2-PK closes a gap in clinical practice because it detects bleeding and nonbleeding tumors and adenoma with high sensitivity and specificity.
