癌前病变与癌前疾病(癌前状态)不同,因前者不一定是独立的疾病,但具有较多的组织病理改变。但癌前病变与癌前疾病之间有一定联系。食管癌组织发生学的形态分期至今了解甚少。要证实癌前病变,首先必须在一定数量的人群中进行随访,在一定时期内有相当数量的病例发展为癌。(这类研究在子宫颈于50年代已有报道,70年代初期在食管癌高发区林县作了类似研究。)其次需直接在食管癌高、低发区人群中进行对比调查予以证实。第 Precancerous lesions differ from precancerous conditions (precancerous conditions) in that the former are not necessarily independent diseases, but have more histopathological changes. However, there is a link between precancerous lesions and precancerous conditions. The morphologic staging of esophageal cancer is still poorly understood. To confirm precancerous lesions, we must first follow-up in a certain number of people. In a certain period of time, a considerable number of cases develop into cancer. (Such studies have been reported in the cervix in the 1950s. A similar study was conducted in Linxian County, a high-incidence area for esophageal cancer, in the early 1970s.) Second, it needs to be directly confirmed by comparative investigations in high- and low-incidence areas of esophageal cancer. The first