Surgical suppression of gastric acid secretion. Lessons from long-term follow-up studies

Management of gastric remnant carcinoma based on the results of a 15-year endoscopic screening program

SUMMARY BACKGROUND DATA

Partial gastrectomy for benign peptic ulcer disease is associated with an increased risk of adenocarcinoma of the gastric remnant, especially in patients who are at least 15 years' postgastrectomy. Increasing evidence of mucosal dysplasia is noted on random gastric biopsy and may serve as a histologic marker in the identification of early cancer of the gastric stump.

METHODS

From an initial group of 233 patients who underwent gastrectomy for benign peptic ulcer disease between 1960 and 1975, 163 patients began yearly flexible gastroscopy and random mucosal biopsy. Routine histologic studies identified either normal or dysplastic epithelium as well as adenocarcinoma. An average of eight biopsies were taken per endoscopic study. All endoscopic studies were performed by surgical residents under the supervision of one surgical attending.

RESULTS

From July 1980 to June 1995, 145 patients completed annual gastroscopy and random biopsy. A total of 2287 endoscopic studies were performed. Fifteen patients were found to have severe dysplasia. Nine (60%) had associated microscopic evidence of adenocarcinoma. Four additional patients had macroscopic adenocarcinoma on endoscopic examination. All 13 patients with cancer were asymptomatic. Six patients continue surveillance who display moderate-to-severe dysplasia alone. The 13 patients with carcinoma underwent completion gastrectomy (R2 nodal dissection) with no evidence of cancer found beyond the gastric wall. These patients averaged 29 years since their original partial gastrectomy.

OBJECTIVE

A prospective screening program for gastric remnant cancer was begun to assess the ability to discover early neoplastic changes on random biopsy and to make treatment decisions regarding the efficacy of completion gastrectomy after discovery of carcinoma.

CONCLUSIONS

Aggressive annual screening using flexible endoscopy and multiple random biopsy may discover cancer in the gastric remnant and can lead to completion curative gastrectomy in asymptomatic people. Patients who are at least 20 years postpartial gastrectomy for benign disease should be considered for annual endoscopic surveillance.

Discovery of early gastric remnant carcinoma. Results of a 14-year endoscopic screening program

Partial gastrectomy for benign ulcer disease has been associated with an increased incidence of mucosal dysplasia and invasive adenocarcinoma, particularly in patients who are 15-20 years postresection. Using a planned protocol of routine endoscopic surveillance with biopsy, 163 patients who were at least 10 years postgastrectomy for benign ulcer disease have undergone screening flexible esophagogastroduodenoscopy (EGD) between July 1980 and August 1994. The completed study group consists of 153 patients who have been examined at least yearly over the 14-year period of surveillance. Routine biopsies from various areas of the gastric remnant have been interpreted for dysplasia or early gastric adenocarcinoma. Patients who evidenced significant dysplasia or adenocarcinoma were offered complete gastrectomy during the study. Results of this ongoing 14-year screening program revealed severe dysplasia of the gastric remnant in 13 patients (8.4%) with eventual findings of adenocarcinoma in seven of this group (54%). These seven patients underwent total gastrectomy with findings of limited disease. Six patients continue to be followed with evidence of dysplasia. During this 14-year screening program, seven patients undergoing completion gastrectomy for early gastric remnant adenocarcinoma continue to be well and free of disease. This aggressive screening program supports the concept that neoplastic change in the gastric remnant is a function of time from the initial gastric resection. Patients identified with early gastric remnant carcinoma benefit by completion gastrectomy. In addition, patients harboring dysplasia in the gastric remnant should continue to be followed in an aggressive screening protocol utilizing random biopsy.

Effects of acid suppression on microbial flora of upper gut

Decreased acid secretion, due to therapy or disease, predisposes to increased bacterial counts in gastric juice. As bacterial numbers increase, the number of nitrate-reducing strains and the concentration of luminal nitrite usually also increase. However, there is controversy (mainly because of assay problems) about whether decreased acid increases generation of N-nitroso compounds: these may be produced by acid or by bacterial catalysis, and the relative contributions of each are still uncertain. Other potentially important factors include ascorbate secretion (can prevent nitrite conversion to nitroso compounds) and the particular spectrum of nitroso compounds produced. Nitrosation of several histamine H2-receptor antagonists has been demonstrated experimentally, but under conditions that are very unlikely to be encountered clinically. Some acid suppressant therapies have been claimed to aid eradication of Helicobacter pylori, but more work is needed to evaluate this. If ulcer treatment regimens do not also address eradication of H. pylori (when present), gastritis will progress, and the recently documented association between H. pylori and gastric carcinoma needs to be considered. Enteric flora probably also increase if acid secretion is markedly reduced: this does not appear to have nutritional consequences but probably reduces the resistance to occasional infections, of which cholera is the best documented.

Ten-year follow-up of a prospective, randomized trial of selective proximal vagotomy with ulcer excision and partial gastrectomy with gastroduodenostomy for treating corporeal gastric ulcer

Between 1975 and 1980, 30 patients with type I corporeal gastric ulcer were randomly allocated to undergo selective proximal vagotomy with ulcer excision or partial gastrectomy with gastroduodenostomy. Sixteen patients underwent selective proximal vagotomy (1 was excluded from the follow-up since microscopic examination of the excised ulcer revealed an early gastric cancer) and 14 underwent partial gastrectomy. No significant differences in the clinical results were found 3 years after surgery. During a median follow-up of 10 years, ulcer recurred in 3 patients after selective proximal vagotomy and in 2 after partial gastrectomy. One patient in each group had recurrent ulcer without symptoms and received no treatment. Two selective proximal vagotomy patients and three partial gastrectomy patients had epigastric pain with or without ulcer. One patient with selective proximal vagotomy underwent a second operation because of epigastric pain and recurrent ulcer. Bowel habits remained unchanged in all but one patient in each group, and mild or moderate dumping was recorded for two patients in each group. Very good or good results (modified Visick scale) were recorded for 11 of 15 patients after selective proximal vagotomy and for 10 of 14 patients after partial gastrectomy. Except for one patient in each group who had moderate dumping, patients classified as Visick III or IV had no symptoms during treatment with antacids or H2-blockers, or had asymptomatic ulcers and needed no treatment. Selective proximal vagotomy reduced the median acid response to insulin hypoglycemia and to pentagastrin by 100% and 80%, respectively, for at least 3 to 5 years, and partial gastrectomy reduced the median acid response to pentagastrin by 97%. In our opinion, selective proximal vagotomy with ulcer excision is an alternative to partial gastrectomy for surgically treating type I gastric ulcer.

Screening for gastric carcinoma in coal miners

This study aimed to determine the prevalence of dyspeptic symptoms and premalignant gastric lesions in coal miners and sex matched population control subjects. Retired coal miners and men from the general population in north Nottinghamshire were sent a dyspepsia questionnaire to fill in, and those with upper gastrointestinal symptoms were invited for gastroscopy and biopsy. A total of 1272 men from the general population and 2099 retired coal miners aged 50-75 years took part in the study. Some 977 of 1272 (76.8%) control subjects and 1715 of 2099 (81.7%) miners replied to the questionnaire. A total of 308 of 977 (31.5%) controls and 620 of 1715 (36.2%) miners were positive for at least one symptom. There was a highly significant difference between the numbers of surface mine and underground workers who reported dyspeptic symptoms (66 of 300 (22%) v 425 of 1083 (32.2%) of p < 0.0001). Histology showed that significantly more miners than controls had acute on chronic gastritis (22 v 11%; p = 0.01) and intestinal metaplasia (23 v 8%; p = < 0.0001). Coal miners may be a suitable group for gastric premalignancy screening using an upper gastrointestinal symptom questionnaire and upper gastrointestinal endoscopy.