They were first characterized in 1907 by Siegfried Oberndorfer, a German pathologist at the University of Munich, who coined the term "karzinoide", or "carcinoma-like", to describe the unique feature of behaving like a benign tumor despite having a malignant appearance microscopically. The recognition of their endocrine-related properties were later described by Gosset and Masson in 1914, and these tumors are now known to arise from the enterochromaffin (EC) and enterochromaffin-like (ECL) cells of the gut. Some sources credit Otto Lubarsch with the discovery.