  Radiative corrections in leading logarithmic approximation are calculated for
the differential cross section of $e^- \mu ^+$ radiative scattering. In
particular the interference term due to photon emission from electron and muon
blocks are calculated in helicity independent and dependent parts. The
calculation is applied to the kinematical conditions of existing DVCS data in
electron-proton collisions. Both helicity odd and helicity even differential
cross sections are considered.
