“Er korrigiert meine Anschauung und führt sie weiter fort.” Kommentare von David von Hansemann zu der Schrift von Theodor Boveri Zur Frage der Entstehung maligner Tumoren (1914)

“He Corrects my View and Develops it Further.” Comments by David von Hansemann on the Monograph by Theodor Boveri Concerning the Origin of Malignant Tumors (1914). According to many authors, the treatise on cancer written by Theodor Boveri in 1914 demonstrates astonishing foresight with respect to contemporary cancer research, in particular with respect to the genomic instability of tumors. In some recent publications, however, it has been claimed that not Boveri but primarily David von Hansemann deserves credit for these chromosomal theories of cancer origin. The claim seems to be unjustified because there are great differences, both in conception and in argumentation, between both opinions. In addition, it has been ignored that von Hansemann himself said that his views “were corrected and developed further by Boveri”. In this paper two obviously unknown comments regarding Boveri's theory by von Hansemann are presented as examples. Furthermore, the paper points out that the pathologist von Hansemann was engaged in the formal genesis of tumors using descriptive methods. By contrast, the embryologist Boveri developed his hypotheses on the basis of the experimentally founded chromosome theory of inheritance in an attempt to explain the etiology or causal genesis of tumors. Thus, it can be concluded that Boveri developed the first genetic cancer theory in the history of medicine.