Tumor invasion and metastasis of malignant tumor invasion is the quality and quantity of cells distributed in the interstitial abnormal phenomenon, tumor cell adhesion, enzymatic degradation, mobile, and a series of matrix multiplication process within the performance. Typically, tumor invasion occurs in malignant tumors, benign but sometimes also showed infiltration of the individual, such as vascular tumors, myxoma and so on. Tumor cells often spread directly (invasion), vascular permeation, lymphatic permeation, serosal and mucosal surfaces such means the spread of the invasion to the surrounding tissue. The performance of various types of tumor invasion may be different, but once the tumor invasion, can be labeled "invasive" to and no infiltration of the "in situ" phase difference.
Tumor invasion and metastasis of malignant cells in tumor metastasis is the primary site from its transit through various channels, to the target tissue does not continue the proliferation of continuous growth, the formation of the same nature of the process of tumor metastasis including begging from, transfer, and growth three main components, the steps at least: the tumor cell groups from the primary tumor invasion and basement membrane adhesion and infiltration in the surrounding stroma or growth and the local capillary endothelial cells of lymphatic capillaries in close contact and broke into the cavity through the wall or Road (such as serous cavities), in blood vessels, lymphatic transport was to survive, while the formation of platelet aggregation start small tumor emboli to reach the target tissue; tumor cells and vascular or lymphatic endothelial cells and capillary basement membrane adhesion or penetration lymphatic capillary wall to the surrounding stromal invasion, continued proliferation in the matrix, the formation of new secondary tumors.Tumor invasion and metastasis are the growth characteristics of malignant tumors, the two are inter-linked to different pathological processes, infiltration is a prelude to the transfer, the transfer must have happened but it does not mean, however, must include a transfer of infiltration process, which together constitute the spread of malignant tumors.