Collaborating with Surgeons to Develop a New Tissue Marker

• Biomedical Applications
• Polymeric Materials
• Research Center for Macromolecules and Biomaterials

Tissue markers enable precise surgical removal of tumors and other potentially malignant growths. In collaboration with surgeons, Toru Yoshitomi developed an advanced marker that resists diffusion, remains in tissues for extended periods, and can be injected using endoscopic needles. He is now advancing its practical application.

Unresolved Issues in Surgical Tissue Marking

Malignant stomach and colorectal tumors develop on the mucosal lining of the digestive tract, rendering them invisible from the outside during open abdominal surgery. To address this, an endoscopic needle is used to inject a tissue marker around a target tumor in advance, providing a visual guide for surgeons during the procedure.

India ink tissue markers, sterilized with high-pressure steam in hospitals, are commonly used in surgeries. However, these markers tend to diffuse and offer poor contrast, making it difficult to distinguish marked areas from surrounding tissues. Additionally, surgeries may be delayed by up to a month due to scheduling conflicts, further reducing the markings’ visibility. Accurate tissue marking is essential for preserving as much healthy tissue as possible, which significantly impacts the patient’s prognosis.

In January 2020, Yoshitomi attended the Young Researchers Exchange Meeting hosted by the Tsukuba Life Science Promotion Association. During the event, he met Dr. Kinji Furuya from the Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery at the University of Tsukuba and learned about the challenges with tissue markers faced by medical practitioners. This meeting initiated a collaboration between the NIMS Tissue Regeneration Materials Group and the University of Tsukuba’s digestive surgery team to develop a new tissue marker.