PGR and neoplasm: Collected data included demographic variables (age, BMI, and menstrual status), tumor characteristics (tumor size, axillary lymph node [N] stage, histological grade, color Doppler ultrasound features including blood flow signal [CDFI], morphology, and aspect ratio), molecular markers (estrogen receptor [ER], progesterone receptor [PR], human epidermal growth factor receptor-2 [HER-2], and Ki-67), and treatment-related factors (chemotherapy regimen).