The present disclosure relates to methods for the treatment, prevention and diagnosis of peripheral T-cell lymphoma using compounds that specifically bind NKp46. Included in particular are compounds that bind NKp46 and deplete tumor cells that express NKp46 at their surface, and pharmaceutical compositions comprising the same. The disclosure also relates to the use of antibodies that specifically bind NKp46 in diagnostic and theranostic assays in the detection and treatment of peripheral T-cell lymphoma.