Lugano classification (PET-CT treatment response)

The Lugano classification is a lymphoma staging system resulting from recommended changes in 2011 to the Cotswolds modified Ann Arbor staging. This article outlines the classification's response to treatment based on PET-CT. 

Also included in the classification are staging and response to treatment based on CT.

Scoring system

The Lugano classification recommends a five-point scale (see also Deauville five-point scale) for response assessment with FDG PET-CT:

1. no uptake or no residual uptake (when used interim) 
2. slight uptake, but below blood pool (mediastinum) 
3. uptake above mediastinal, but below or equal to uptake in the liver
4. uptake slightly to moderately higher than liver
5. markedly increased uptake or any new lesion (on response evaluation)

Non-progressive disease

• complete metabolic response (CMR)
  • score of 1, 2 or 3 in nodal or extranodal sites with or without a residual mass
• partial metabolic response (PMR)
  • score of 4 or 5 with reduced uptake compared with baseline and residual mass(es) of any size
• stable disease or no metabolic response
  • score of 4 or 5 with no obvious change in FDG uptake

Progressive disease

• score 4 or 5 in any lesion with an increase in intensity of FDG uptake from baseline (and/or new FDG-avid foci consistent with lymphoma)