Letter: gastric cancer and pernicious anaemia - only a minority of UK pernicious anaemia patients have had a gastroscopy--authors' reply.

Abstract

We read with interest the letter by Pritchard and Hooper, in which they reported data from an online questionnaire survey of members of the Pernicious Anaemia Society.1 Their main result was that less than a quarter (n = 131, 23.3%) of the 561 respondents had undergone endoscopy following the diagnosis of pernicious anaemia, with biopsies taken in only 19.2% (n = 108). The relevant endoscopic finding in these patients was diagnoses of one neuroendocrine tumour, 20 gastric polyps, and 30 cases of atrophic gastritis, while no gastric cancer was found, with other patients unaware of histological findings. There are some considerations we would like to make. In our opinion all patients with suspected pernicious anaemia should undergo gastroscopy with biopsies for several reasons. First, the diagnosis needs to be histologically confirmed, because other reasons for micronutrient malabsorption may be responsible for the cobalamin deficiency and/or the macrocytic anaemia. Besides pernicious anaemia, cobalamin deficiency may be due to food-cobalamin malabsorption, a disorder characterised by the inability to release cobalamin from food or its binding proteins, which is usually caused by atrophic gastritis, Helicobacter pylori infection, or long-term treatment with anti-secretory agents or biguanides.2, 3 Second, in about one-third of cases, an active H. pylori infection may be found at histopathological evaluation of gastric biopsies, and in another 20% of cases the presence of polymorphonucleate inflammatory cells together with a positive serological titre of anti-H. pylori IgG antibodies may be a witness to previous contact with this bacterium. In these cases, eradication treatment is indicated, and may reduce the active gastric inflammation and in some cases, it may even reverse the atrophic damage of gastric mucosa.4, 5 Third, the clinical onset of pernicious anaemia occurs many years after the onset of the gastric inflammation, ultimately leading to gastric atrophy of oxyntic mucosa, intrinsic factor deficiency, and cobalamin malabsorption, as the body's stores of cobalamin generally take several years to be emptied. Pernicious anaemia is a condition with an increased risk for gastric neoplasm, as shown by our work and that of others.6, 7 Finally, one more reason to perform a baseline gastroscopy with bioptic mapping in all patients is that the presence of a gastric neoplastic lesion at the first diagnosis of pernicious anaemia cannot be excluded on a clinical basis only. The above cited survey showed that only 30 (22.9%) cases out of the 131 who underwent gastroscopy reported a diagnosis of atrophic gastritis. This is an unexpected proportion in a population of pernicious anaemia patients, as the atrophy of the gastric oxyntic mucosa is by definition present in all patients with pernicious anaemia as this is the cause of the intrinsic factor deficiency involved in cobalamin malabsorption. Thus, the fact that less than a quarter of pernicious anaemia patients had atrophic gastritis may be explained by missing corporal biopsies at gastroscopy, or by a diagnosis different from pernicious anaemia. Indeed, only 19% of patients had biopsies during gastroscopy. Finally, we fully agree with the authors that patients with suspected pernicious anaemia should be strongly encouraged to undergo a baseline gastroscopy with antral and corporal biopsies to confirm the diagnosis and to determine the baseline risk of gastric neoplastic lesions. Afterwards, a future surveillance should be scheduled at 3-years intervals according to the guidelines on precancerous conditions and lesions in the stomach.8 The authors’ declarations of personal and financial interests are unchanged from those in the original article.6