In 1905, Louis B. Wilson, M.D., was appointed chief pathologist and director of laboratories at Mayo Clinic. Seeking a faster way to identify cancerous tissue, Dr. Wilson placed a tissue sample removed from a patient during surgery on the hospital’s windowsill, where it quickly froze. He then dyed the specimen and mounted it on a slide. The result showed whether or not the specimen was malignant.

This breakthrough answered Dr. William J. Mayo’s request for pathologists to develop a method of determining whether a growth is cancerous while the patient was still in surgery.

Dr. Wilson was an expert at microscope-based research and a pioneer in visualizing diseased tissues. His frozen section technique reduced the need for multiple surgical procedures and further expanded the renown of the Mayo’s surgical practice.

Today, one of the distinctive attributes of Mayo Clinic is the strong collaboration of surgeons and pathologists. Diagnostic facilities are still located in close proximity to operating rooms, fulfilling Dr. Mayo’s vision of a single surgical session that minimizes trauma to the patient, speeds treatment and improves outcomes.