论文部分内容阅读
许多固体瘤,包括结肠癌、肺癌、乳癌、子宫颈癌、膀胱癌、前列腺癌、胰腺癌、皮肤癌等的生长可粗分成两个过程:首先为无血管过程,肿瘤尚未与血管网络相通,营养物质的取得,以及排泄物质的去除,必须扩散至邻近的健康组织进行,因之肿瘤的生长十分缓慢,直径不过数毫米,呈扁平状,医学上大多难以诊断。即使一些恶性的肿瘤,也常经年停滞在这一过程。肿瘤的癌细胞紧密地互相粘附,因此也不侵袭附近组织,也不转移它处。
The growth of many solid tumors, including colon, lung, breast, cervix, bladder, prostate, pancreas, skin, etc., can be roughly divided into two processes: first an avascular process in which the tumor has not communicated with the vascular network, The acquisition of nutrients, and the removal of excreted substances, must spread to neighboring healthy tissues. Because of the slow growth of tumors, the tumors are only a few millimeters in diameter and are flat, making it largely undetectable in medicine. Even some malignant tumors, often stagnated in this process. The cancer cells of the tumor adhere closely to each other and therefore do not invade nearby tissue nor metastasize to it.