In our search for answers following the debate in recent years, we came upon an interesting article¹. We believe that Prof. George Babiniotis, Emeritus and Honorary Professor of Linguistics and former Rector (2000–2006) of the University of Athens, has excellent and credible thoughts. Our position is based on his reasoning. In the article, Prof. Babiniotis explains the following: 

“Theragnostics is the better term. In theranostics, the second part of the word “nostics” refers more to the disease than diagnostics. Linguistically, the better approach is a synergy of the two words therapo-gnostics because “thera” alone does not refer to therapy and could be confused with the Greek word for hunting.” 

Babiniotis argues that it is essential to understand that the key to the term “theragnostics” is “gnosis”, not “agnosis”, whereas “agnosis” is derived from the Greek word agnosia , which means a lack of knowledge. Thus, “theragnostics” is a better term emphasising knowledge, and as the article elegantly summarises “, nuclear medicine with its combination of molecular imaging and molecular radiotherapy does indeed offer knowledge-based precision medicine”. 

Reference: ¹https://link.springer.com/article/10.1007/s00259-018-4204-z