Cancer lymphatic dissemination

Ovarian cancer usually is confined to the abdominal cavity, but spread can occur to the lung, liver, and less commonly, bone or brain. Disease is spread by direct extension, peritoneal seeding, lymphatic dissemination, and blood-borne metastasis. 

A variety of diseases affect the lymphatic system early in their time course. For example, many cancers spread by lymphatic dissemination, and HIV, fungal, and bacterial infections are located primarily in the lymph nodes. The high prevalence of lymph node involvement in disease is due to the role of lymphatic tissue in the provision of the body s immune response. Intralymphatic and interstitial administration are two efficient access routes. However, the oral route may also prove to be important for the lymphatic uptake of lipophilic drags and macromolecules. 

Schimanski, C. C., R. Bahre, I. Gockel, T. Junginger, N. Simiantonaki, S. Biesterfeld, T. Achenbach, T. Wehler, P. R. Galle, and M. Moehler. 2006. Chemokine receptor CCR7 enhances intrahepatic and lymphatic dissemination of human hepatocellular cancer. Oncol Rep 16 109-113. 

Formation of regional lymph node metastasis can be an important step in dissemination of cancer cells. In colorectal cancer, lymph node metastasis frequently occurs in patients (7, 8) and is an important factor in staging the disease. In particular, the metastatic lymph node ratio (LNR number of metastatic lymph nodes/number of examined lymph nodes) is predictive of overall survival (OS) and disease-free survival (DFS) in colorectal cancer patients (9, 10). Hence, an animal model of colorectal cancer with measurable lymphatic metastasis that allows for rapid evaluation of the effects of candidate treatment regimens on primary tumor growth and lymph node metastasis would be of great value. 

The two primary pathways of metastasis are hematogenous and lymphatic. Other, less-common modes of disease spread include dissemination via cerebrospinal fluid and transabdominal spread within the peritoneal cavity. Tumors are constantly shedding neoplastic cells into the systemic circulation or surrounding lymphatics. This process may begin early in the hfe of the tumor and often increases with time. The time course for metastasis depends largely on the biology of the tumor. Breast cancer, for example, tends to metastasize very early. Not all of the shed cancer cells, or seeds, result in a metastatic lesion. The seed must first find the appropriate soU, or an environment suitable for growth. This process is illustrated in the diverse patterns... 

Expression of ras p21 was consistently increased in the invasive component of the primary tumor as compared with the intraductal tumor. In addition, a high level of p21 expression was seen in tumor emboli in lymphatics and blood vessels as compared with the contiguous tumor in parenchymal tissue. It is suggested that markedly enhanced p21 expression is associated with earlier stages (invasion and dissemination) of aggressive breast cancers. 

Most cancers that occur within the abdomen or pelvis will disseminate by three different routes these are hematogenous metastases, lymphatic metastases and through peritoneal spaces to surfaces of the abdominal cavity. In a substantial number of patients with abdominal or pelvic malignancy surgical treatment failure is isolated to the resection site or to peritoneal surfaces. 

Metastatie disease is the primary cause of death for most cancer patients. Metastasis is a process that allows many tumors to expand to distant areas of the body from the primary tumor localization. The dissemination of tumor cells to those areas requires tirmor cell migration and invasion into the extracellular matrix and then into the blood and lymphatic organs (Stefier-Stevenson, Aznavoorian and Liotta 1993 Steeg 2006 Pantcl, Brakenhoff and Brandt 2008). The epithelial to mesenchymal transition (EMT) process is the principal mean through which metastasis occurs, namely. 

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