前　　言此分类主要依据肿瘤显微镜下表现 ,即常规光学显微镜下所见到的细胞类型和组织结构。“tumor”是“neoplasm”的同义词。瘤样病变是指那些在临床或形态学上与肿瘤类似的病变 ,但其生物学行为并非肿瘤。在此提出此概念 ,是因为它们在鉴别诊断时可能会给我们带来一定的困 Preface This classification is mainly based on the performance of tumor microscopy, that is seen under conventional light microscope cell types and organizational structure. “Tumor” is a synonym for “neoplasm.” Tumor-like lesions are those that are clinically or morphologically similar to tumors but whose biological behavior is not tumor. This concept is presented here because they may give us some difficulty in differential diagnosis