PGR and neoplasm: In a univariate analysis, other factors associated with improved pCR rates were ER negativity (P < 0.001), PR negativity (P < 0.001), HER2 positivity (P < 0.001), tumor size ≤2 cm (P < 0.001), negative lymph nodes (P < 0.001), and high tumor grade (P < 0.001).