An appropriate treatment interval does not affect the prognosis of patients with breast Cancer.

Purpose: Major public health emergencies may lead to delays or alterations in the treatment of patients with breast cancer at each stage of diagnosis and treatment. How much do these delays and treatment changes affect treatment outcomes in patients with breast cancer?

Methods: This review summarized relevant research in the past three decades and identified the effect of delayed treatment on the prognosis of patients with breast cancer in terms of seeking medical treatment, neoadjuvant treatment, surgery, postoperative chemotherapy, radiotherapy, and targeted therapies.

Results: Delay in seeking medical help for ≥12 weeks affected the prognosis. Surgical treatment within 4 weeks of diagnosis did not affect patient prognosis. Starting neoadjuvant chemotherapy within 8 weeks after diagnosis, receiving surgical treatment at 8 weeks or less after the completion of neoadjuvant chemotherapy, and receiving radiotherapy 8 weeks after surgery did not affect patient prognosis. Delayed chemotherapy did not increase the risk of relapse in patients with luminal A breast cancer. Every 4 weeks of delay in the start of postoperative chemotherapy in patients with luminal B, triple-negative, or HER2-positive breast cancer treated with trastuzumab will adversely affect the prognosis. Targeted treatment delays in patients with HER2-positive breast cancer should not exceed 60 days after surgery or 4 months after diagnosis. Radiotherapy within 8 weeks after surgery did not increase the risk of recurrence in patients with early breast cancer who were not undergoing adjuvant chemotherapy.

Conclusion: Different treatments have different time sensitivities, and the careful evaluation and management of these delays will be helpful in minimizing the negative effects on patients.