Researchers at Washington University in St. Louis are working on a photothermal treatment to destroy tumors. The research is published in Small. The team, led by Younan Xia, uses gold nanocages, which are injected into the body and selectively accumulate in tumors. Later on, the tumors are bathed in laser light. The surrounding tissue is barely warmed, but the nanocages convert light into heat, killing the malignant cells. After injecting some mice with the nanocages and others with a buffer solution, the mice were subjected to a diode laser for 10 minutes. PET scans of the two groups showed the tumors of the nanocage-injected mice were significantly fainter than those of the buffer-injected mice. The tumors in the nanocage-injected mice also were later found to have histological signs of cellular damage.