Dinis-Ribeiro Mário, da Costa-Pereira Altamiro, Lopes Carlos, Moreira-Dias Luís
Department of Gastroenterology, Portuguese Oncology Institute, Porto, Portugal.
J Gastroenterol Hepatol. 2007 Oct;22(10):1594-604. doi: 10.1111/j.1440-1746.2007.04863.x.
The follow-up of patients with atrophic chronic gastritis or intestinal metaplasia may lead to early diagnosis of gastric cancer. However, to-date no cost-effective model has been proposed. Improved endoscopic examination using magnification chromoendoscopy together with non-invasive functional assessment with pepsinogen serum levels are accurate in the diagnosis of intestinal metaplasia (extension) and minute dysplastic lesions. The aim of this study was to assess the feasibility and cost-effectiveness of a follow-up model for patients with atrophic chronic gastritis and intestinal metaplasia based on gastric mucosal status using magnification chromoendoscopy and pepsinogen.
A cohort of patients with lesions as severe as atrophic chronic gastritis were followed-up according to a standardized protocol using magnification chromoendoscopy with methylene blue and measurement of serum pepsinogen I and II levels. A single node decision tree and Markov chain modeling were used to define cost-effectiveness of this follow-up model versus its absence. Transition rates were considered time-independent and calculated using primary data following cohort data analysis. Costs, quality of life and survival were estimated based on published data and extensive sensitivity analysis was performed.
A total of 100 patients were successfully followed-up over 3 years. Seven cases of dysplasia were diagnosed during follow-up, all among patients with incomplete intestinal metaplasia at baseline, six of whom had extensive (pepsinogen I to II ratio <3) incomplete intestinal metaplasia. For those individuals with atrophic chronic gastritis or complete intestinal metaplasia, a yearly measurement of pepsinogen levels or an endoscopic examination on a 3-yearly basis would cost 455 euros per quality-adjusted life year (QALY) gain. Endoscopic examination and pepsinogen serum level measurement on a yearly basis would cost 1868 euros per QALY for patients with extensive intestinal metaplasia.
The follow-up of patients with atrophic chronic gastritis or intestinal metaplasia is both feasible and cost-effective if improved accurate endoscopic examination of gastric mucosa together with non-invasive assessment of gastric mucosal status are used to identify individuals at high-risk for development of gastric cancer.
对萎缩性慢性胃炎或肠化生患者进行随访可能有助于早期诊断胃癌。然而，迄今为止尚未提出具有成本效益的模型。使用放大色素内镜改善内镜检查，并结合胃蛋白酶原血清水平进行非侵入性功能评估，在诊断肠化生（范围）和微小发育异常病变方面是准确的。本研究的目的是评估基于放大色素内镜和胃蛋白酶原的胃黏膜状态，对萎缩性慢性胃炎和肠化生患者进行随访模型的可行性和成本效益。
根据标准化方案，对一组患有萎缩性慢性胃炎等严重病变的患者进行随访，采用亚甲蓝放大色素内镜检查，并测量血清胃蛋白酶原I和II水平。使用单节点决策树和马尔可夫链模型来定义该随访模型与不进行随访相比的成本效益。转换率被视为与时间无关，并在队列数据分析后使用原始数据进行计算。成本、生活质量和生存率根据已发表的数据进行估计，并进行了广泛的敏感性分析。
共有100名患者成功随访3年。随访期间诊断出7例发育异常，均在基线时为不完全肠化生患者中，其中6例有广泛（胃蛋白酶原I与II比值<3）不完全肠化生。对于那些患有萎缩性慢性胃炎或完全肠化生的个体，每年测量胃蛋白酶原水平或每3年进行一次内镜检查，每获得一个质量调整生命年（QALY）的成本为455欧元。对于广泛肠化生的患者，每年进行内镜检查和测量血清胃蛋白酶原水平，每QALY的成本为1868欧元。
如果使用改进的准确胃黏膜内镜检查以及胃黏膜状态的非侵入性评估来识别胃癌发生高危个体，对萎缩性慢性胃炎或肠化生患者进行随访是可行且具有成本效益的。
