EurekAlert -- A new mechanism explaining how tumors escape the body’s natural immune surveillance has recently been discovered at EPFL (Ecole Polytechnique Fédérale de Lausanne) in Switzerland. The study shows how tumors can create a tolerant microenviroment and avoid attack by the immune system by mimicking key features of lymph nodes. The discovery, published in Science and in Science Express, online March 25, 2010, underscores the role of the lymphatic system in cancer and may open up new possibilities for cancer treatment.