High-dose chemotherapy (CTM) for breast cancer

Area of Science:

• Oncology
• Hematology
• Pharmacology

Background:

• Carmustine-based regimens for breast cancer can cause pulmonary injury.
• High-dose chemotherapy with autologous hematopoietic stem cell rescue is a treatment option for advanced breast cancer.

Purpose of the Study:

• To design and implement a novel mitoxantrone-based high-dose chemotherapy regimen (CTM) for breast cancer.
• To minimize pulmonary toxicity compared to carmustine-based regimens.
• To evaluate the efficacy and safety of the CTM regimen in various stages of breast cancer.

Main Methods:

• A cohort of 191 breast cancer patients received high-dose chemotherapy (cyclophosphamide, thiotepa, mitoxantrone) followed by stem cell rescue.
• Patients with Stage II/III disease also received radiation and tamoxifen (if applicable).
• Treatment-related mortality, pulmonary toxicity, cardiac events, and event-free survival (EFS) were assessed.

Main Results:

• The 5-year EFS for Stage II/IIIA patients with ≥10 positive lymph nodes was 62%.
• 5-year EFS rates were 44% for Stage IIIB and 17% for Stage IV breast cancer.
• Treatment-related mortality was 3%, with no delayed interstitial pneumonitis observed.
• Cardiac events were reduced after mitoxantrone dose adjustment.

Conclusions:

• The CTM regimen is associated with low treatment-related mortality and minimal pulmonary toxicity.
• CTM demonstrates excellent outcomes for Stage II/IIIA breast cancer patients with ≥10 involved axillary lymph nodes.
• Further investigation into mitoxantrone dose adjustment for cardiac safety is warranted.