The CPS-EG score is a scoring system that helps doctors better assess the prognosis for breast cancer. The score was developed for breast cancer patients who receive chemotherapy before surgery (neoadjuvant chemotherapy). The score takes various factors into account, such as the size of the tumour before and after chemotherapy, as well as various characteristics of the tumour cells. A higher score indicates a higher risk. This assessment can help in deciding what further treatment is necessary after surgery.