近红外成像,肿瘤细胞 z-bo 2020-08-18 614

　　Researchers at the University of Pennsylvania have used near-infrared (NIR) imaging technology to create a new strategy that allows surgeons to distinguish tumors from non-tumors, thereby making tumor resections more effective. Among patients undergoing surgery, 20% to 50% died due to local tumor recurrence. This shows that doctors cannot remove all diseased tissues from the cancer site. It is difficult to identify the edge of the tumor during surgery. Surgeons usually need to do this by looking at the tumor and feeling the difference with their fingers.

　　In order to find another way, David Holt, professor of surgery at the University of Pennsylvania School of Veterinary Medicine, Sunil Singhull, associate professor at the Perelman School of Medicine at the University of Pennsylvania, and colleagues are all focusing on near-infrared (NIR) imaging technology. it is. They chose to test a dye called indocyanine green (ICG), which is the only FDA-approved NIR contrast agent. Compared with normal tissues, tumor blood vessels have so-called "leaky" walls due to their rapid growth, so ICG will accumulate more in tumor tissues.

　　As Singhal said: "Since the FDA first approved ICG in 1958, it has been used to detect tissue perfusion and removal research. However, our team has used ICG to solve the classic problem of tumor surgery. We are trying new strategies to Solution: Prevent local recurrence. Our research provides a new use for the old dye, in which the old dye gives ICG to mice with certain types of lung cancer. 15 days after the injection, when the mice developed cancer, they found that NIR can be used Distinguish between tumor lung tissue and normal lung tissue, macroscopically, these tumors developed into cancer in mice. The researchers then conducted a technical evaluation of eight dogs owned by the owner. These dogs are of breed, size, and size. Spontaneous lung cancer and Pennsylvania. I was sent to the Veterinary College for surgery. The day before the operation, I received an intravenous injection of ICG, and the surgeon tried to use NIR to visualize the tumor during the operation to distinguish it from normal tissue Come on. He said: "This method works well, and the fluorescence displayed by the tumor is sufficient for surgeons to quickly identify the tumor during the operation. This method works well in naturally occurring large animal models and is therefore recognized. Try it in the human body: "

　　Human clinical trials are the last step. A preliminary study at the University of Pennsylvania Hospital recruited 5 patients with lung or breast cancer. At the same time before the operation, each patient received an ICG injection. During the operation, the surgeon will remove the tumor, use NIR to image the tumor and perform a biopsy. With strong fluorescence, this technology has been proven to be applicable to human tumors

　　In the four patients, doctors can easily distinguish tumors from non-tumors based on vision and perception. However, in the fifth patient, CT and PET scans showed that the tumor was an isolated mass, while NIR imaging showed that the lung, which was considered healthy, was fluorescent. "This patient was found to have diffuse micro-tumors in multiple areas of the lung, sometimes referred to as stage I local disease, leading to tumors. His biopsy showed that he had received chemotherapy. Several other research groups have begun to study NIR in Other applications in cancer surgery, but this group is a mouse model with a large scale. This is the first use of this method in spontaneous animal models and human clinical trials. A disadvantage of this method is that ICG may also be inflamed by tissue absorb.

　　Therefore, in some patients with inflamed tissue around the tumor, it is difficult or impossible to distinguish the tumor from the inflamed tissue. Holt said that researchers at the University of Pennsylvania are looking for selective targeted contrast agents for tumor cell markers to avoid this problem.