In line with this perspective, SLN, as the first leukocyte niche to encounter tumor antigens from the primary tumor, enables the immune response to orchestrate spatiotemporally, which is critical for tumor vaccination 1, 6. Given the much higher risks of surgical complications and more exhaustive histological examinations in axillary dissection over no axillary dissection, the former is also suggested as an overtreatment 5. However, clinical follow-up studies show that for BC patients with a moderate tumor burden in SLN, no axillary dissection does not show inferiority in disease-free survival compared with axillary dissection 3, 4. Surgical treatment of breast cancer (BC) generally involves the dissection of sentinel lymph nodes (SLNs) where tumor cells are detected 1, 2. This study indicates a clinical value of metastatic SLN in immunoadjuvant therapy. Ultimately, CTLs in patch-driven metastatic SLNs could long-termly maintain tumor antigen-specific memory, protecting against high-incidence BC recurrence in female mice.

Delivered aPD-1 and LDH confer CTLs with upregulated glycolytic activity, promoting CTL activation and cytotoxic killing via metal cation-mediated shaping. Genes associated with citric acid cycle and oxidative phosphorylation are enriched in activated CD8 + T cells (CTLs) from metastatic SLNs. The flex-patch is implanted on the postoperative wound and spatiotemporally releases immunotherapeutic anti-PD-1 antibodies (aPD-1) and adjuvants (magnesium iron-layered double hydroxide, LDH) into the SLN. Here we leverage an immune-fueling flex-patch to animate metastatic SLNs with personalized antitumor immunity. Clinical updates suggest conserving metastatic sentinel lymph nodes (SLNs) of breast cancer (BC) patients during surgery however, the immunoadjuvant potential of this strategy is unknown.

Sentinel node biopsy shorthand