1. A method for evaluating evolution of tumoural lesions, said method comprising the steps of: providing a first image of said tumoural lesions, said first image being made at a first time instant; providing a second image of said tumoural lesions, said second image being made at a second time instant that is later than said first time instant; delineating a border of said tumoural lesions in said first image and said second image; registration of said tumoural lesions in said first image and said second image; segmenting said tumoural lesions in said first image and said second image into concentric areas; quantifying changes of at least one functional parameter between said concentric areas in said first image and respective corresponding concentric areas in said second image; visualizing said changes in a two-dimensional or three-dimensional model of said tumoural lesions, said visualizing comprising colouring two-dimensional or three-dimensional concentric shapes in said two-dimensional or three-dimensional model using colours depending on said changes of said at least one functional parameter, wherein said colours comprise: a first colour for changes of said at least one functional parameter indicative for regressive tumour lesions or regressive tumour area within one lesion; a second colour for changes of said at least one functional parameter indicative for stable tumour lesions or stable tumour area within one lesion; and a third colour for changes of said at least one functional parameter indicative for progressive tumour lesions or progressive tumour area within one lesion; and determining a first percentage of regressive tumour lesions, a second percentage of stable tumour lesions, and a third percentage of progressive tumour lesions.