 While other physicians such as Ernst von Bergmann suggested surgical removal of the entire larynx, Virchow was opposed to it because no successful operation of this kind had ever been done.The British surgeon Morell Mackenzie, performed a biopsy in 1887 and sent it to Virchow, who identified it as "pachydermia verrucosa laryngis".Virchow affirmed that the tissues were not cancerous, even after several biopsy tests.