Monitoring and Toxicity Management in HR+/HER2− mBC

The panel focuses on multidisciplinary monitoring and proactive toxicity management for patients with hormone receptor-positive, HER2-negative metastatic breast cancer (HR+/HER2− mBC), particularly as treatment moves into later-line targeted therapy. NP Kathryn Post discusses the value of more frequent in-person or virtual follow-up when initiating new regimens, allowing the care team to reinforce education, identify adverse events early, assess adherence, and reduce the burden of frequent clinic travel through telehealth and local laboratory testing. She also highlights the important role of caregivers as note takers, advocates, and additional observers who can provide insight into symptoms that may be underreported during clinic visits. Dr. Jennifer Hutchinson then reviews practical monitoring and supportive care considerations for PI3K pathway-directed therapy, including glucose monitoring and early consideration of antidiabetic therapy when clinically appropriate. For stomatitis, she emphasizes prophylactic dexamethasone mouthwash beginning on day 1, salt or baking soda rinses, good oral hygiene, and avoidance of alcohol-based mouthwash. Early recognition can allow treatment interruption or dose reduction when needed, supporting continued therapy and quality of life.