Yamaguchi N, Watanabe S, Maruyama K, Okubo T
Department of Environmental Epidemiology, University of Occupational and Environmental Health, Kitakyushu.
Jpn J Cancer Res. 1990 Nov;81(11):1109-17. doi: 10.1111/j.1349-7006.1990.tb02521.x.
A mathematical model incorporating the processes of both cancer induction and subsequent tumor growth has been developed. The model was applied to incidence data of stomach classified into histologic subtypes: papillary adenocarcinoma (PAP), well and moderately differentiated tubular adenocarcinomas (WEL and MOD), poorly differentiated adenocarcinoma (POR), mucinous adenocarcinoma (MUC) and signet-ring cell carcinoma (SIG). The multistage theory was assumed for cancer induction as in the Armitage-Doll model. For the period of growth, exponential growth was assumed and clinical surfacing was formulated as a stochastic process related to tumor diameter. The number of stages in cancer induction and the tumor growth rate were simultaneously estimated for each histologic subtype using the maximum likelihood procedure. The present model showed better fits than the Armitage-Doll model in most histologic subtypes except WEL, PAP, WEL and MOD, which are characterized as differentiated subtypes with less mucous production, showed different features from POR, MUC and SIG: 1) the number of stages was estimated to be larger, 2) the differences in incidence rates between males and females were more marked, and 3) males tended to have larger growth rates in PAP and MOD, while in POR, MUC and SIG, females had larger values. The present study showed that an analysis by histologic subtypes is of importance in stomach cancer and that the period of tumor growth should not be ignored when formulating a model of the natural history of stomach cancer.
已经建立了一个包含癌症诱发过程和后续肿瘤生长过程的数学模型。该模型应用于根据组织学亚型分类的胃癌发病率数据：乳头状腺癌（PAP）、高分化和中分化管状腺癌（WEL和MOD）、低分化腺癌（POR）、黏液腺癌（MUC）和印戒细胞癌（SIG）。与阿米蒂奇-多尔模型一样，假定癌症诱发遵循多阶段理论。对于生长阶段，假定为指数生长，并将临床出现表述为与肿瘤直径相关的随机过程。使用最大似然法同时估计每种组织学亚型的癌症诱发阶段数和肿瘤生长速率。除了WEL、PAP、WEL和MOD（这些被归类为黏液分泌较少的分化型亚型）外，本模型在大多数组织学亚型中比阿米蒂奇-多尔模型拟合得更好，它们表现出与POR、MUC和SIG不同的特征：1）估计阶段数更多；2）男性和女性发病率的差异更显著；3）在PAP和MOD中男性往往具有更大的生长速率，而在POR、MUC和SIG中，女性具有更大的值。本研究表明，按组织学亚型进行分析在胃癌研究中很重要，并且在构建胃癌自然史模型时不应忽视肿瘤生长阶段。
