Broitman S A, Velez H, Vitale J J
Adv Exp Med Biol. 1981;135:155-81. doi: 10.1007/978-1-4615-9200-6_9.
Through the efforts of Correa, Cuello, Haenszel, Tannenbaum and others it was learned that the incidence of gastric cancer in certain areas of Narino (Colombia) was among the highest in the world. These areas of high risk for gastric cancer were adjacent to an area of substantially lower risk. Gastric biopsies from healthy volunteers residing in the "high risk" area exhibited a greater incidence of superficial gastritis and chronic atrophic gastritis with and without intestinal metaplasia than those from the low risk area. The latter pathological finding is considered to be a precursor lesion to gastric cancer. Volunteers from the "low risk" area as well as individuals from Cali in the coastal region and Cartegena on the coast, also exhibited a similar spectrum of pathology but at a substantially reduced frequency. Natives of both cities were also at lower risk for gastric cancer than inhabitants of Narino. It was found that the water supply of the "high risk" area contained a higher concentration of nitrate than water in the "low risk" area. Correa et al. hypothesized that the high nitrate concentrations of well water contributed to the formation of N-nitroso compounds in the stomachs of these individuals early in life. The occurrence of this putative carcinogen in combination with the abrasive action of dietary grains contributed to a series of mutations in the gastric epithelium progressing through a sequence of pathologic changes, loss of gastric acid and culminating in gastric cancer. In the current report individuals in a Medellin population who were admitted with abdominal complaints and were found to be iron deficient exhibited the same spectrum of gastric pathology described by previous investigators. Superficial gastritis, chronic atrophic gastritis and achlorhydria have also been described in association with chronic iron deficiency (and/or associated nutritional defects) per se. The development of these lesions are likely to occur within the first two decades of life when iron requirements are maximal. It is suggested that these changes preceed the development of gastric cancer. Bacterial colonization of the achlorhydric stomach may facilitate nitrate reduction and the formation of a putative carcinogen N-nitroso compound(s) from nitrate in the water supply. Additionally, the effects of chronic iron deficiency on host immune defense may compromise these mechanisms and permit tumor growth with minimal immune intervention.
通过科雷亚、奎洛、海恩斯尔、坦嫩鲍姆等人的努力，人们了解到纳里尼奥（哥伦比亚）某些地区的胃癌发病率位居世界前列。这些胃癌高风险地区与一个风险低得多的地区相邻。居住在“高风险”地区的健康志愿者的胃活检显示，与低风险地区相比，浅表性胃炎、伴有或不伴有肠化生的慢性萎缩性胃炎的发病率更高。后一种病理发现被认为是胃癌的前期病变。来自“低风险”地区的志愿者以及沿海地区卡利和海岸边卡塔赫纳的居民，也表现出类似的病理特征，但频率大幅降低。这两个城市的本地人患胃癌的风险也低于纳里尼奥的居民。研究发现，“高风险”地区的供水所含硝酸盐浓度高于“低风险”地区的水。科雷亚等人推测，井水的高硝酸盐浓度促使这些人在生命早期胃中形成N-亚硝基化合物。这种假定致癌物的出现，再加上谷物饮食的研磨作用，导致胃上皮发生一系列突变，经历一系列病理变化，胃酸分泌减少，最终发展为胃癌。在当前的报告中，麦德林一群因腹部不适入院且被发现缺铁的人，表现出了先前研究人员所描述的相同胃病理特征。浅表性胃炎、慢性萎缩性胃炎和胃酸缺乏也与慢性缺铁（和/或相关营养缺陷）本身有关。这些病变可能在生命的头二十年铁需求最大时出现。有人认为这些变化先于胃癌的发生。胃酸缺乏的胃中的细菌定植可能会促进硝酸盐还原，并从供水中的硝酸盐形成一种假定的致癌物N-亚硝基化合物。此外，慢性缺铁对宿主免疫防御的影响可能会损害这些机制，并在最小的免疫干预下使肿瘤生长。
