Effect of Vitamin D Supplementation on the Efficacy and Adverse Effects of Neoadjuvant Therapy in Patients with Breast Cancer

Before the start of treatment and every 3 weeks thereafter, participants will receive injections of vitamin D2 at a dosage of 10 mg until the completion of neoadjuvant therapy. They will undergo the standard neoadjuvant regimen, which includes the 10 mg injection of vitamin D2 per cycle during the therapy. The dosage of neoadjuvant drugs may be tailored based on the physician's clinical judgment.

Participants will receive the standard neoadjuvant regimen during each cycle of neoadjuvant therapy. The dosage of the neoadjuvant drugs may be tailored based on the physician's clinical judgment.