Vascular invasion

Vascular invasion refers to the penetration of cancer cells into the blood vessels or lymph vessels. This process is a critical step in the spread of cancer, known as metastasis.

Overview

Vascular invasion is a significant factor in the prognosis of many types of cancer. It is often associated with a higher risk of metastasis, which can lead to the spread of cancer to other parts of the body. The presence of vascular invasion can influence the treatment plan for a patient, as it may indicate a need for more aggressive therapy.

Mechanism

The process of vascular invasion involves several steps. First, cancer cells detach from the primary tumor. They then degrade the extracellular matrix, a network of proteins and carbohydrates that provides structural support to cells. This degradation allows the cancer cells to invade the surrounding tissue.

Once in the tissue, the cancer cells can penetrate the walls of blood or lymph vessels. This penetration is facilitated by angiogenesis, the formation of new blood vessels. The cancer cells can then enter the bloodstream or lymphatic system and travel to other parts of the body.

Clinical significance

Vascular invasion is a key factor in the staging of cancer. It is used in the TNM staging system, a widely used system for classifying the extent of cancer spread. In this system, the presence of vascular invasion is indicated by the letter 'V'.

The detection of vascular invasion can be challenging. It is often identified through histopathology, the microscopic examination of tissue. However, this method can miss small areas of invasion. Newer techniques, such as immunohistochemistry, are being developed to improve the detection of vascular invasion.

See also

• Cancer metastasis
• Angiogenesis
• TNM staging system
• Histopathology
• Immunohistochemistry