Managing Disease Burden, ILD Risk, and CNS Progression in HER2 Positive Metastatic Breast Cancer

This segment addresses key clinical challenges in managing patients with high visceral disease burden receiving ADC-based therapy. The discussion reinforces that symptomatic lung involvement should not preclude use of trastuzumab deruxtecan when respiratory symptoms are tumor driven. Practical guidance is provided on interstitial lung disease monitoring, including imaging frequency, recognition of asymptomatic radiographic changes, and thresholds for treatment interruption. The panel also discusses sequencing decisions if CNS metastases develop, emphasizing the role of tucatinib-based regimens and the selective use of local CNS therapy. Patient-reported outcomes and quality-of-life considerations are woven into the discussion, highlighting how response depth, toxicity expectations, and treatment durability shape shared decision making at therapy initiation.