Histologic and nuclear grading (NG) have been widely used to predict the prognosis in patients with advanced breast cancer. However, NG has been criticized as a non-standard (several grading schemes used) and subjective (significant interobserver variability) method for predicting the biologic behavior of this tumor. Our results on 106 invasive ductal breast carcinomas demonstrate that NG correlates with morphometric prognostic index (MPI) (p < 0.007) (lower value of MPI is connected with lower NG of 1-2 and better prognosis), with estrogen receptor (p < 0.0002) and progesteron receptor status (p < 0.04) (hormonal receptor positive tumors having lower NG). NG correlates with s-phase fraction (SPF), p < 0.04, values lower than 9.6% corresponding to lower NG. We consider NG to give important information about the biologic behavior of the tumors under observation, demonstrating a good correlation with more established parameters such as MPI and SPF.