Dual-Stimuli Injectable Platforms for Localized Breast Cancer Therapy

Locoregional breast cancer recurrence remains a significant therapeutic challenge, largely driven by limited drug selectivity and toxicity to surrounding healthy tissues. This Mini-Review examines the emerging potential of pH- and temperature-responsive formulations as injectable drug delivery systems designed to achieve preferential targeting of malignant cells. A range of advanced platforms─from smart hydrogels to hybrid constructs such as pH-sensitive liposomes embedded within thermoresponsive hydrogel matrices─are discussed, with emphasis on key design principles and synthesis strategies enabling environmental responsiveness. Among the technologies reviewed, liposome-in-hydrogel hybrid systems─still largely unexplored in breast cancer therapy─stand out for their capacity to enhance encapsulation of lipophilic therapeutics, improve formulation stability, streamline manufacturing, and provide sustained, spatially controlled drug release. Finally, critical physicochemical, mechanical, and biological characterization studies that are needed to rigorously evaluate the translational and clinical potential of these materials for the treatment of locoregional recurrent breast cancer are outlined.