Ludwig Rehn (1849-1930)--pioneering findings on the aetiology of bladder tumours.

One hundred and six years ago, the surgeon Ludwig Rehn from Frankfurt am Main held a pioneering lecture in Berlin about the possible origins of bladder tumours. He thereby gave the decisive impulse for cancer research in general and specifically for the investigation of aetiological factors involved in the development of urogenital tract tumours. Thereafter, this resulted in an intensified scientific discussion addressing this issue. Although the detailed evaluation of the causes finally contributing to tumour growth is still ongoing, the work of Ludwig Rehn on bladder tumours among aniline workers considerably promoted the establishment of urology as a specialised field within German clinical medicine and is therefore a milestone in the history of medicine.