Moshe Shike

Prevention of Colorectal Cancer by Colonoscopic Polypectomy

BACKGROUND The current practice of removing adenomatous polyps of the colon and rectum is based on the belief that this will prevent colorectal cancer. To address the hypothesis that colonoscopic polypectomy reduces the incidence of colorectal cancer, we analyzed the results of the National Polyp Study with reference to other published results. METHODS The study cohort consisted of 1418 patients who had a complete colonoscopy during which one or more adenomas of the colon or rectum were removed. The patients subsequently underwent periodic colonoscopy during an average follow-up of 5.9 years, and the incidence of colorectal cancer was ascertained. The incidence rate of colorectal cancer was compared with that in three reference groups, including two cohorts in which colonic polyps were not removed and one general-population registry, after adjustment for sex, age, and polyp size. RESULTS Ninety-seven percent of the patients were followed clinically for a total of 8401 person-years, and 80 percent returned for one or more of their scheduled colonoscopies. Five asymptomatic early-stage colorectal cancers (malignant polyps) were detected by colonoscopy (three at three years, one at six years, and one at seven years). No symptomatic cancers were detected. The numbers of colorectal cancers expected on the basis of the rates in the three reference groups were 48.3, 43.4, and 20.7, for reductions in the incidence of colorectal cancer of 90, 88, and 76 percent, respectively (P < 0.001). CONCLUSIONS Colonoscopic polypectomy resulted in a lower-than-expected incidence of colorectal cancer. These results support the view that colorectal adenomas progress to adenocarcinomas, as well as the current practice of searching for and removing adenomatous polyps to prevent colorectal cancer.

LACK OF EFFECT OF A LOW-FAT, HIGH-FIBER DIET ON THE RECURRENCE OF COLORECTAL ADENOMAS

BACKGROUND We tested the hypothesis that dietary intervention can inhibit the development of recurrent colorectal adenomas, which are precursors of most large-bowel cancers. METHODS We randomly assigned 2079 men and women who were 35 years of age or older and who had had one or more histologically confirmed colorectal adenomas removed within six months before randomization to one of two groups: an intervention group given intensive counseling and assigned to follow a diet that was low in fat (20 percent of total calories) and high in fiber (18 g of dietary fiber per 1000 kcal) and fruits and vegetables (3.5 servings per 1000 kcal), and a control group given a standard brochure on healthy eating and assigned to follow their usual diet. Subjects entered the study after undergoing complete colonoscopy and removal of adenomatous polyps; they remained in the study for approximately four years, undergoing colonoscopy one and four years after randomization. RESULTS A total of 1905 of the randomized subjects (91.6 percent) completed the study. Of the 958 subjects in the intervention group and the 947 in the control group who completed the study, 39.7 percent and 39.5 percent, respectively, had at least one recurrent adenoma; the unadjusted risk ratio was 1.00 (95 percent confidence interval, 0.90 to 1.12). Among subjects with recurrent adenomas, the mean (+/-SE) number of such lesions was 1.85+/-0.08 in the intervention group and 1.84+/-0.07 in the control group. The rate of recurrence of large adenomas (with a maximal diameter of at least 1 cm) and advanced adenomas (defined as lesions that had a maximal diameter of at least 1 cm or at least 25 percent villous elements or evidence of high-grade dysplasia, including carcinoma) did not differ significantly between the two groups. CONCLUSIONS Adopting a diet that is low in fat and high in fiber, fruits, and vegetables does not influence the risk of recurrence of colorectal adenomas.

Randomized Comparison of Surveillance Intervals after Colonoscopic Removal of Newly Diagnosed Adenomatous Polyps

BACKGROUND The identification and removal of adenomatous polyps and post-polypectomy surveillance are considered to be important for the control of colorectal cancer. In current practice, the intervals between colonoscopies after polypectomy are variable, often a year long, and not based on data from randomized clinical trials. We sought to determine whether follow-up colonoscopy at three years would detect important colonic lesions as well as follow-up colonoscopy at both one and three years. METHODS Patients were eligible if they had one or more adenomas, no previous polypectomy, and a complete colonoscopy and all their polyps had been removed. They were randomly assigned to have follow-up colonoscopy at one and three years or at three years only. The two study end points were the detection of any adenoma, and the detection of adenomas with advanced pathological features (defined as those > 1 cm in diameter and those with high-grade dysplasia or invasive cancer). RESULTS Of 2632 eligible patients, 1418 were randomly assigned to the two follow-up groups, 699 to the two-examination group and 719 to the one-examination group. The percentage of patients with adenomas in the group examined at one and three years was 41.7 percent, as compared with 32.0 percent in the group examined at three years (P = 0.006). The percentage of patients with adenomas with advanced pathological features was the same in both groups (3.3 percent). CONCLUSIONS Colonoscopy performed three years after colonoscopic removal of adenomatous polyps detects important colonic lesions as effectively as follow-up colonoscopy after both one and three years. An interval of at least three years is recommended before follow-up colonoscopy after both one and three years. An interval of at least three years is recommended before follow-up examination after colonoscopic removal of newly diagnosed adenomatous polyps. Adoption of this recommendation nationally should reduce the cost of post-polypectomy surveillance and screening.

Current use and clinical outcome of home parenteral and enteral nutrition therapies in the United States

BACKGROUND & AIMS Home nutrition support, especially when delivered parenterally, is very costly. The aim of this study is to examine current usage of home parenteral and enteral nutrition (HPEN) in the United States and the quality of therapy outcome. METHODS Medicare HPEN use from 1989 to 1992 was analyzed to assess use, growth, and costs. National Registry information collected on 9288 patients treated with HPEN from 1985 to 1992 was used to assess disease distribution and therapy outcome. RESULTS In the United States, there were approximately 40,000 parenteral and 152,000 enteral home patients in 1992. The usage of HPEN doubled between 1989 and 1992, and a large proportion was in patients with short survival. The prevalence of HPEN in the United States was 4-10 times higher than in other Western countries. Outcome data showed both therapies were relatively safe. The primary disease strongly influenced survival and rehabilitation, and age, per se, was not a reason to deny HPEN. CONCLUSIONS Predicted quality survival at home for several months, rather than a specific diagnosis, seems to be the soundest justification for HPEN. Its role in terminal conditions and patients without primary gastrointestinal diseases needs further evaluations.

A prospective, randomized trial of early enteral feeding after resection of upper gastrointestinal malignancy

OBJECTIVE The purpose of the study was to determine whether early postoperative enteral feeding with an immune-enhancing formula (IEF) decreases morbidity, mortality, and length of hospital stay in patients with upper gastrointestinal (GI) cancer. SUMMARY BACKGROUND DATA Early enteral feeding with an IEF has been associated with improved outcome in trauma and critical care patients. Evaluable data documenting reduced complications after major upper GI surgery for malignancy with early enteral feeding are limited. METHODS Between March 1994 and August 1996, 195 patients with a preoperative diagnosis of esophageal (n = 23), gastric (n = 75), peripancreatic (n = 86), or bile duct (n = 11) cancer underwent resection and were randomized to IEF via jejunostomy tube or control (CNTL). Tube feedings were supplemented with arginine, RNA, and omega-3 fatty acids, begun on postoperative 1, and advanced to a goal of 25 kcal/kg per day. The CNTL involved intravenous crystalloid solutions. Statistical analysis was by t test, chi square, or logistic regression. RESULTS Patient demographics, nutritional status, and operative factors were similar between the groups. Caloric intake was 61% and 22% of goal for the IEF and CNTL groups, respectively. The IEF group received significantly more protein, carbohydrate, lipids and immune-enhancing nutrients than did the CNTL group. There were no significant differences in the number of minor, major, or infectious wound complications between the groups. There was one bowel necrosis associated with IEF requiring reoperation. Hospital mortality was 2.5% and median length of hospital stay was 11 days, which was not different between the groups. CONCLUSION Early enteral feeding with an IEF was not beneficial and should not be used in a routine fashion after surgery for upper GI malignancies.

Long term tolerance of high dose three-dimensional conformal radiotherapy in patients with localized prostate carcinoma.

The current study was undertaken to evaluate the incidence and predictors of late toxicity in patients with localized prostate carcinoma treated with high dose three‐dimensional conformal radiotherapy (3D‐CRT).

A prospective randomized trial of total parenteral nutrition after major pancreatic resection for malignancy.

ObjectivesThe authors examined the impact of adjuvant total parenteral nutrition after major pancreatic resection for malignancy. Summary Background DataPrevious studies have suggested a benefit to perioperative nutritional support for patients undergoing major gastrointestinal surgery. MethodsA prospective, randomized study was conducted using patients who had undergone a major pancreatic resection with randomization on postoperative day one to either receive or not receive adjuvant total parenteral nutrition. ResultsNo benefit could be demonstrated by the use of adjuvant parenteral nutrition in this setting. Complications were significantly greater in the group receiving total parenteral nutrition. These complications tended to be those associated with infection. ConclusionsRoutine applications of postoperative parenteral nutrition to patients undergoing major pancreatic resection for malignancy cannot be recommended. Further studies are required to determine the reason that infectious complications in these patients are increased.

Malabsorption and Mucosal Abnormalities of the Small Intestine in the Acquired Immunodeficiency Syndrome

Diarrhea and weight loss may accompany the acquired immunodeficiency syndrome. We studied 30 patients with the syndrome, 20 of whom had diarrhea and weight loss and 10 of whom did not. Patients with identifiable enteric infections or small intestinal Kaposis sarcoma were excluded. Malabsorption was common in the patients with diarrhea and weight loss, as shown by abnormal D-xylose and 14C-glycerol-tripalmitin absorption tests. In these patients, duodenal biopsy specimens showed a histiocytic infiltrate containing numerous acid-fast organisms in 5 and a mild-moderate chronic inflammation in 13. In asymptomatic patients, duodenal biopsy specimens were normal in 6 and showed chronic inflammation in 4. These results suggest that malabsorption is common in patients with the acquired immunodeficiency syndrome with chronic diarrhea and may contribute to their weight loss.

Metabolic Bone Disease in Patients Receiving Long-Term Total Parenteral Nutrition

We have prospectively investigated calcium and bone metabolism in 16 patients receiving total parenteral nutrition for periods ranging from 7 to 89 months. In 12 patients, bone biopsies at 6 to 73 months after the start of parenteral nutrition showed osteomalacia. Plasma 25-hydroxyvitamin D levels were normal in all patients. Seven persons developed hypercalcemia, and 10 had hypercalciuria with a negative calcium balance. Serum phosphorus was normal and plasma parathyroid hormone level, normal or decreased. Three patients with the severest form of the disease had vitamin D withdrawn from their solutions. Subsequently, urinary calcium decreased, and serum calcium became normal; two persons reverted to a positive calcium balance. Thus, patients receiving total parenteral nutrition may develop metabolic bone disease characterized by osteomalacia, hypercalcemia, hypercalciuria, and a negative calcium balance. This may be caused by both defective mineralization and increased bone resorption induced by vitamin D, its metabolites, or another unrecognized factor.

Direct percutaneous endoscopic jejunostomies for enteral feeding

Abstract Background: Enteral feeding through percutaneous endoscopic gastrostomy (PEG) is increasingly utilized in hospitals, homes, and institutions. However, PEGs have two major limitations: (1) risk for aspiration, which occurs in up to 30% of patients, and (2) it does not allow enteral feeding in patients with gastric outlet obstruction, gastroparesis, or gastric resection. Methods: A new endoscopic method for placement of direct percutaneous endoscopic jejunostomy (DPEJ) was attempted in 150 patients with or without a history of major abdominal surgery. Patients were followed-up until tube utilization ceased because of death or resumption of oral feeding. Results: There were 129 (86%) successful procedures and 21 (14%) unsuccessful attempts. Procedure-related complications included nine (6%) incisional infections. Bleeding, abscess, and colonic perforation each occurred in one patient (.6%), and all required surgical intervention. On long-term follow-up (n = 97), tube malfunction occurred in 3 patients (3%) and aspiration in 3 (3%). Duration of tube use in this population was 113 ± 173 days. Conclusions: DPEJs can be performed successfully with a low complication rate. Enteral feeding through DPEJs drastically reduces aspiration, which commonly occurs with PEG feeding. DPEJs allow feeding and hydration of patients with gastric outlet obstruction due to cancer who are not surgical candidates, eliminate the need for intravenous hydration and feeding, and can cut costs of hospitalization and treatment. (Gastrointest Endosc 1996;44:536-40.)