The present invention relates to a method for assisting with lymphoma prognosis. The prognosis of therapeutic response of patients with lymphoma is difficult. Based on a study of advanced stage DLBCL patients, the inventors showed that medical imaging such as 18F-FDG-PET/CT can provide a prognostic radiomic signature combining metrics reflecting tumor dissemination and tumor burden. In another aspect, the invention relates to a computer software comprising instructions to implement at least a part of a method according to the invention. In yet another aspect, the invention relates to a computer-readable non-transient recording medium on which a software is registered to implement a method according to the invention.rnrnScientific publication(s):rnJ Nucl Med, 2020 Jan, Cottereau AS. Et al., 18F-FDG PET Dissemination Features in Diffuse Large B-Cell Lymphoma Are Predictive of Outcome, doi: 10.2967/jnumed.119.229450