Samuel Sontag: Dissertatio inauguralis medica de metastasi sive sede morborum mutata oder: Wie sich öffters eine Kranckheit in die andere verwandele. Praeside Hoffmanno.

Recamier (1829) is credited with coining the term metastasis with respect to cancer. It is evident that Hoffmann and his pupil Sontag used the term nearly 100 years earlier in this general thesis on disease. They did not apply it specifically to cancer though they mentioned tumors twice in the dissertation, on pp. 12 and 14. The title of Sontag's thesis may be translated as Inaugural medical dissertation on metastasis or the altered seat of disease. How one disease often turns into another.

Digital facsimile from the Internet Archive at this link.