Total gastrectomy: nutritional status after different reconstruction techniques. An experimental study

[Fat absorption after total gastrectomy in rats submitted to Roux-en-Y or Rosanov-like double-transit technique]

PURPOSE

Steatorrhea is one of the most common complications in reconstruction after total gastrectomy. Many reconstruction techniques after total gastrectomy have been developed in order to avoid these undesirable effects, but each one of them has some inconvenience. In this experiment, a modified Rosanov technique that keeps duodenal transit, evaluation of fat absorption after gastrectomy was tested.

METHODS

Three groups of rats with the same characteristics were used. Total gastrectomy was performed in two groups: one was operated on and transit was reestablished by the Roux-en-Y technique (group Y), while the other was submitted to the modified Rosanov technique (group R). Following surgery, a handmade hyper fatty diet (11% of fat) was offered. A third group (control - group C) was not operated but was submitted to the same conditions of the other groups, and used for reference steatocrit values. The animals underwent laparotomy 14 days after surgery and had their feces collected from cecum to determine their steatocrit by analysis of their values.

RESULTS

Steatocrit values for groups R and C (mean 5.16% and 4.15% respectively) were similar (p > 0.1), while group Y had significantly higher values (mean = 28.18%, p = 0.0001 - p < 0,05). This was attributed to the fact that group R animals had their duodenal transit patent, decreasing the complications expected in the Roux-en-Y reconstruction.

CONCLUSIONS

Steatorrhea in the modified Rosanov technique was similar to the control group, while Roux-en-Y reconstruction presented higher steatorrhea and fat malabsorption.

[Nutritional status and dietary assessment of patients with gastrectomy]

BACKGROUND

Nutrition is a crucial factor in gastric resection surgery and the most suitable alimentary canal reconstruction method must be considered in order to reduce the risk of malnutrition. The cause of postgastrectomy malnutrition has not been clearly determined, but the mechanisms behind malnutrition are evidently multifactorial.

AIM

To evaluate the nutritional status of patients who underwent different reconstructive procedures after total or subtotal gastrectomy.

PATIENTS AND METHODS

Fifty patients who have undergone gastrectomy for 0.5-39 years were assessed. The surgical procedures used were Billroth I in 7, Billroth II in 26, Henley in 3 and Roux-en-Y in 14 of the patients. Twenty one of them have followed gastrectomy for cancer. The nutritional status was evaluated by subjective global assessment, dietary recall and anthropometry.

RESULTS

According to subjective global assessment, 6 of 50 patients were mild malnourished. The mean body mass index was 22 4.75 kg/m2, the average daily calorie intake was 1624 477 Kcal. Of the patients operated for cancer, those who underwent subtotal gastrectomy followed by Roux-en-Y presented higher body mass index. No relationship between the period of time since surgery with body mass index or with calorie intake was found.

CONCLUSIONS

Among patients operated for cancer, subtotal gastrectomy with Roux-en-Y reconstruction is associated with better nutritional status. Factors other than low calorie intake are the cause of weight loss in patients with gastrectomy.

Effects of vitamin B12 and folate deficiencies on DNA methylation and carcinogenesis in rat liver

Deficiencies of the major dietary sources of methyl groups, methionine and choline, lead to the formation of liver cancer in rodents. The most widely investigated hypothesis has been that dietary methyl insufficiency results in abnormal DNA methylation. Vitamin B12 and folate also play important roles in DNA methylation since these two coenzymes are required for the synthesis of methionine and S-adenosyl methionine, the common methyl donor required for the maintenance of methylation patterns in DNA. The aim of this study was to review the effects of methyl-deficient diets on DNA methylation and liver carcinogenesis in rats, and to evaluate the role of vitamin B12 status in defining carcinogenicity of a methyl-deficient diet. Several studies have shown that a methyl-deficient diet influences global DNA methylation. Evidence from in vivo studies has not clearly established a link between vitamin B12 and DNA methylation. We reported that vitamin B12 and low methionine synthase activity were the two determinants of DNA hypomethylation. Choline- or choline/methionine-deficient diets have been shown to cause hepatocellular carcinoma in 20-50% of animals after 12-24 months. In contrast, the effect of vitamin B12 withdrawal, in addition to choline, methionine and folate, induced hepatocellular carcinoma in less than 5% of rats.

Nutrient malassimilation following total gastrectomy

BACKGROUND

The aim of the study was to elucidate the degree and the pathophysiology of abdominal symptoms, malnutrition and malassimilation after total gastrectomy.

METHODS

In 174 consecutive patients, with potentially curative total gastrectomy for gastric malignancy, subjective symptoms and objective parameters of malassimilation were evaluated.

RESULTS

Abdominal symptoms were present in 86% of the patients. In spite of a high daily calorie intake (median 37.8 kcal/kg body weight) mean body mass index had been decreasing since good health. Anaemia was found in 46%, sideropenia in 31% and oesophagitis in 26%. Mean faecal fat excretion was 17.4 (1.4) g/day and mean fat malassimilation 14.8% (1.1) of the intake. A shortened small-bowel transit was measured in 21.7% of the patients, and bacterial overgrowth was present in 37.7%.

CONCLUSIONS

Malassimilation post total gastrectomy seems to be multifactorial. Shortened small-bowel transit and subsequent dyssynchrony of pancreatic enzyme supply seem to be of major importance.

[The Longmire gastrectomy in the animal model: postoperative changes in fat resorption and the hormones cholecystokinin and secretin]

In this animal study we investigated the absorption of free fatty acids and triglycerides after gastrectomy. The levels of the hormones cholecystokinin and secretin were measured in response to a controlled enteral fat load (Lipofundin 20% MCT emulsion). We studied fat absorption in three groups of animals: the gastrectomy group in which lipid emulsion was administered in the duodenum, and two groups of controls that received the same infusion in the duodenum or stomach, respectively. Infusing the fat load directly into the duodenum, rather than the stomach, resulted in delayed absorption of fatty acids. In the gastrectomized animals there was, in addition, increased absorption of triglycerides. Medium- and long-chain fatty acids were found to be an adequate stimulus for secretion of the gastrointestinal hormones cholecystokinin (CCK) and secretin. In the gastrectomized group, higher baseline levels of both CCK and secretin were observed. CCK showed no response to the lipid stimulus, whereas a secretin response was observed over and above the raised baseline level. The gastrectomized animals showed a markedly restricted growth rate, as measured by body weight; however, they continued to gain weight in a linear fashion up to the end of the study period. No alterations in morphology of CCK-secreting cells were found.

Resection margin in patients with gastric cancer associated with esophageal invasion: clinicopathological study

We investigated the correlations between resection margin involvement by carcinoma and a number of clinicopathological features in patients with gastric cancer and esophageal invasion. From January 1968 to December 1988, 1,040 patients with carcinoma of the stomach underwent gastric resection. Thirty-nine patients had tumor infiltration of the esophagus on histological examination of the resected specimens. The patients were divided into two groups on microscopic examination: those in whom the resection margin was less than 5 mm wide, and those in whom it exceeded 5 mm microscopically. There were 6 and 33 patients in the narrow and wide margin groups, respectively. There were statistically significant differences in tumor size, depth of cancer invasion, and macroscopic appearance between the two groups. The risk of resection margin involvement was high in tumors with the following features: large Borrmann type 4 tumor (macroscopic appearance and size) and infiltrative carcinoma (depth of invasion).