Diet and colorectal cancer: current evidence for etiology and prevention.

The etiology of colorectal cancer (CRC) involves the interaction of cell molecular changes and environmental factors, with a great emphasis on diet components. But the paths connecting lifestyle characteristicas and the colorectal carcinogenesis remain unclear. Several risk factors are commonly found in western diets, such as high concentrations of fat and animal protein, as well as low amounts of fiber, fruits and vegetables. A large number of experimental studies have found a counteractive effect of fiber on neoplasia induction, especially in relation to fermentable fiber (wheat bran and cellulose). Epidemiological correlation studies have also indicated that a greater ingestion of vegetables, fruit, cereal and seeds is associated to a lower risk for colorectal neoplasia. Moreover, beneficial properties of fiber (especially from vegetable sources) were documented in more than half of case-control studies. Nevertheless, recent epidemiological data from longitudinal and randomized trials tended not to support this influence. Future research should evaluate what sources of fiber provide effective anti-neoplasic protection, carrying out interventional studies with specific fibers for longer periods. Red meat, processed meats, and perhaps refines carbohydrates are also implicated in CRC risk. Recommendantions to decrease red meat intake are well accepted, although the total amount and composition of specific fatty acids may have distinct roles in this setting. Current evidence favors the substitution of long and medium-chain fatty acids and arachidonic acid for short-chain fatty acids and eicosapentaenoic acid. Excess boy weight and excess energy intake inducing hyperinsulinemia have been also associated to CRC, as well as personal habits such as physical inactivy, high alcohol consumption, smoking and low consumption of folate and methionine. Thus, current recommendations for decreasing the risk of CRC include dietary measures such as increased plant food intake; the consumption of whole grains, vegetables and fruits; and reduced red meat intake.

Pharmacological nutrition in inflammatory bowel diseases.

Inflammatory Bowel Diseases--ulcerative colitis and Crohn's disease--are chronic gastrointestinal inflammatory diseases of unknown etiology. Decreased oral intake, malabsorption, accelerated nutrient losses, increased requirements, and drug-nutrient interactions cause nutritional and functional deficiencies that require proper correction by nutritional therapy. The goals of the different forms of nutritional therapy are to correct nutritional disturbances and to modulate inflammatory response, thus influencing disease activity. Nutritional intervention may improve outcome in certain individuals; however, because of the costs and complications of such therapy, careful selection is warranted. Total parenteral nutrition has been used to correct and prevent nutritional disturbances and to promote bowel rest during active disease, mainly in cases of digestive fistulae with a high output. Its use should be reserved for patients who cannot tolerate enteral nutrition. Enteral nutrition is effective in inducing clinical remission of disease in adults and promoting growth in children. Recent research has focused on the use of specific nutrients as primary treatment agents. Although some reports have indicated that glutamine, short-chain fatty acids, antioxidants and immunonutrition with omega-3 fatty acids are an important therapeutic alternative in the management of inflammatory bowel diseases, the beneficial reported effects have yet to be translated into the clinical practice. The real efficacy of these nutrients still need further evaluation through prospective and randomized trials.

Early results of the treatment of internal hemorrhoid disease by infrared coagulation and elastic banding: a prospective randomized cross-over trial.

BACKGROUND: Rubber band ligation (RBL) is probably the most commonly performed nonsurgical therapy for hemorrhoidal disease. Infrared coagulation (IRC) is one of the most recent advances based on the use of "heat". Recent studies have demonstrated similar efficacy for both modalities. This prospective randomized crossover trial compared IRC and RBL for pain, complications, effectiveness, and patient satisfaction and preference in the treatment of internal hemorrhoids (IH). METHODS: Patients were randomized to receive either RBL (Group A) or IRC (Group B) for treatment of the first hemorrhoid; in a second procedure two weeks later, patients underwent the other procedure on the second hemorrhoid, thereby serving as their own control. The procedure preferred by the patient was employed two weeks later for the third hemorrhoid. Post-treatment pain was evaluated on a visual analog scale and on the basis of the percentage of patients requiring analgesics. Bleeding and early outcome of treatment were also recorded, together with the patient's satisfaction. RESULTS: A total of 94 patients were included in this study (47 patients in each group). At 30 minutes and 6 hours after treatment, pain scores were significantly higher in patients treated with RBL than in those treated with IRC (p<0.01). There was no significant difference in pain scores between the two procedures immediately and 24 hours after the procedures (p<0.05). After 72 hours and one week, the pain scores for RBL and IRC were similar. The percentage of patients using analgesics was significantly higher in RBL group than in IRC group at 6 hours (29.6% vs. 19.2%, respectively; p<0.05) and 24 hours (22.5% vs. 13.5%, respectively; p<0.05) after treatment. However, significant differences were not noted at 72 hours (12.7% vs. 6.4%; p<0.05) and one week (5.6% vs. 7.1%; p>0.05) after the procedures. There were significantly higher incidences of bleeding immediately, 6 hours, and 24 hours after RBL compared to IRC (immediate: 32.4% vs. 4.3%; 6 hours: 13.4% vs. 3.6%, 24 hours: 26.8% vs. 10.2%, respectively; p<0.01). However, there were no significant differences noted regarding the incidence of bleeding between the two groups at 72 hours. Complications were more likely after RBL than IRC, however this difference was not significant (p>0.05). Overall, 91 patients (96.8%) were successfully treated and 93 patients (99%) were very satisfied with the treatment. In the third treatment session, 50% of patients selected RBL and 50% chose IRC. CONCLUSIONS: Both RBL and IRC were well-accepted and highly efficacious methods for the treatment of IH; in addition, both procedures were associated with relatively minor complications. However, RBL was associated with more pain than IRC in the 24-hour postoperative period.

Surgical treatment of haemorrhoidal disease with CO2 laser and Milligan-Morgan cold scalpel technique.

OBJECTIVE: To prospectively compare immediate postoperative results of the surgical treatment of haemorrhoidal disease (HD) by Milligan-Morgan technique using either the CO(2) laser or cold scalpel. METHODS: Forty patients with grade III/IV HD were prospectively randomized to undergo surgical treatment (Milligan-Morgan) using either the CO(2) laser (group A) or the cold scalpel method (group B). Data were compared regarding postoperative pain, complications, healing time, return to normal activity and patient satisfaction. Patients were blinded to treatment method until the completion of the study. Postoperative outcomes were assessed by patient questionnaire and outpatient follow-up visits. Pain was assessed by Visual Analogue Scale and analgesic consumption. RESULTS: Twenty patients were randomized into each group and were comparable relative to mean age, gender and grade of HD. There were no statistically significant differences regarding postoperative pain measured (P =0.17) or consumption of oral (P = 0.741) and parenteral analgesics (P = 0.18) between the two groups. Mean pain score at the first bowel movement was significantly higher in group A (P = 0.035), although the use of analgesics was similar in both the groups. There were no differences regarding complications, mean healing time, return to normal activities and patient satisfaction. CONCLUSION: There were no differences in the immediate results after Milligan-Morgan haemorrhoidectomy using either the CO(2) laser or cold scalpel regarding postoperative pain, complications, healing time, return to normal activities or patient satisfaction.

[Chagasic megacolon. Treatment by abdominal recto-sigmoidectomy with mechanical colo-rectal termino-lateral anastomosis. Preliminary results]. / Megacólon chagásico. Tratamento pela retossigmoidectomia abdominal com anastomose mecânica colorretal término-lateral. Resultados preliminares.

Abdominal rectosigmoidectomy with end to side colorectal mechanical anastomosis is proposed as a new technique for surgical treatment of Chagasic megacolon. The rectum is sectioned and closed at the level of the peritoneal reflexion. The end of the descending colon is anastomosed to the posterior surface of the rectum, as distal as possible, using the intraluminal stapler (Ethicon CDH33). The final result of the operation is similar to Duhamel-Haddad technique with the advantage of being a one stage operation. Forty-three patients with chagasic megacolon were operated on during the period 1989-1994. Twenty-seven were female and 16 were male with ages ranging from 23 to 76 and a mean of 46.1 years. Results obtained were satisfactory; there were no deaths; only three postoperative complications occurred (6.9%). Only one of these (dehiscence of the rectal cupula) was specific for the proposed technique. The two others were intestinal obstruction, due to volvulus of the small intestine in one case and to adhesions in the other. All complications were managed by surgery. All patients are being followed regularly and up to the present time they report daily bowel movements, passing well-formed stools. There are no complaints of fecal incontinence sexual function or disturbed formation of fecaloma in the rectal stump. The colorectal anastomosis was ample in all patients. Since this is a one stage operation with a low rate of complications, the short hospital stay largely compensates the cost of the mechanical suturing device. Regarding recurrences, a long follow-up period of at least 10 years is necessary to evaluate the real effectiveness of this technique.

Stapled anastomosis in colorectal surgery.

The authors review their experience with stapled anastomosis in colorectal and ileorectal resections for malignant and benign lesions of the large bowel. They describe the technique and results in a series of 49 patients (24 with cancer of the rectum and rectosigmoid junction; six with familial polyposis, associated with cancer in four; 12 with chagastic megacolon; three, Crohn's disease; two, ulcerative colitis; and one each, diverticular sigmoiditis and ischemic sigmoiditis). Anterior resection was performed in 38 patients and total colectomy with ileorectal anastomosis in 11. Main complications and mortality are presented. They conclude that stapled anastomosis is an efficient method for intestinal reconstruction after resection for malignant and benign lesions of the large bowel.