Malignant tumors are abnormal cells that grow and spread rapidly, invading and damaging nearby tissues. Metastasis is the process by which these cells spread from the primary tumor site to other parts of the body. This can happen through a variety of pathways, including:
Direct Spread
Direct spread occurs when malignant cells directly invade nearby tissue. The cells can travel through the bloodstream or lymphatic system and spread to other organs.
Lymphatic Spread
The lymphatic system is a network of vessels and nodes that are part of the immune system. Malignant cells can travel through the lymphatic system and spread to other parts of the body.
Hematogenous Spread
Hematogenous spread is the spread of malignant cells through the bloodstream. The cells can travel to other parts of the body, such as the liver, lungs, and brain.
Transplantation
Transplantation is the transfer of malignant cells from one site to another. This can happen when a tumor is surgically removed and then transplanted to another part of the body.
Seeding
Seeding is the spread of malignant cells through the body via the body's own cells. This can occur when the cells attach to other cells and travel to other parts of the body.