Morphology of Immunomodulation in Breast Cancer Tumor Draining Lymph Nodes Depends on Stage and Intrinsic Subtype

Maximilian Seidl,Oliver Schilling,Jochen Maurer,Kai Franke,Astrid Vaihinger,Moritz Bader,Klaudia Schrenk,Ulrich F Wellner,Jens Pfeiffer,Bettina Herde,Thalia Erbes,Linda Hoffmann,Peter Bronsert,Paul Fisch,Martin Werner,Rumyana Todorova

doi:10.1038/s41598-018-23629-3

Abstract

Cancer research of immune-modulating mechanisms mainly addresses the role of tumor-infiltrating immune cells. Mechanisms modulating the adaptive immune system at the primary activation site – the draining lymph node (LN) – are less investigated. Here we present tumor-caused histomorphological changes in tumor draining LNs of breast cancer patients, dependent on the localization (sentinel LN vs. non-sentinel LN), the tumor size, the intrinsic subtype and nodal metastatic status. The quantitative morphological study was conducted in breast cancer patients with at least one sentinel LN and no neoadjuvant therapy. All LNs were annotated considering to their topographical location, stained for IgD/H&E, digitized and quantitatively analyzed. In 206 patients, 394 sentinels and 940 non-sentinel LNs were categorized, comprising 40758 follicles and 7074 germinal centers. Subtype specific immunomorphological patterns were detectable: Follicular density was higher in LNs of Her2 enriched hormone receptor positive and triple-negative breast cancers whereas hormone receptor positive breast cancers showed more macrophage infiltrations in the LN cortex. Follicles are rounder in metastatic LNs and non-sentinel LNs. The identified immunomorphological changes reflect different underlying immunomodulations taking place in the tumor-draining LNs and should therefore be considered as possible prognostic and predictive markers for LN metastasis and therapy associated immunomodulation.

Highlights

lymph node (LN) metastasis is crucial in tumor evolution and associated with an adverse outcome in most solid tumors
The current focus of cancer research in immune-modulating mechanisms mainly addresses the role of tumor-infiltrating immune cells as therapeutic targets[15,16], representing the effector site of tumor promoting immunity
In 206 patients, 394 sentinel, 512 level I and 428 level II and III LNs were categorized for LN circumference (1515.40–170385.30 μm, median 36512.90 μm) and area (76017.10 μm2–338119557.90 μm[2], median 35422800.90 μm2), follicle circumference (120.40–18511.00 μm, median 844.00 μm) and area (946.10 μm2–6372006.90 μm[2], median 44695.05 μm2), germinal center circumference (74.20–12241.10 μm, median 554.75 μm) and area (399.40 μm2–2677011.90 μm[2], median 20370.70 μm2) and–if present – metastases circumference (276.60–566460.00 μm, median 55372.80 μm) and area (2060.00 μm2–269337442.60 μm[2], median 21580975.30 μm2)

Summary

Introduction

LN metastasis is crucial in tumor evolution and associated with an adverse outcome in most solid tumors. The LN compartments can concentrate antigens, help to produce corresponding antibodies, and recruit immune cells[1,2]. Tumor draining lymph vessels and endothelial venules. – triggered by the tumor – are forming the pre-metastatic niche in tumor draining LNs7,8. The current focus of cancer research in immune-modulating mechanisms mainly addresses the role of tumor-infiltrating immune cells as therapeutic targets (such as the PD1/PDL1 axis)[15,16], representing the effector site of tumor promoting immunity. The identification of mechanisms modulating the adaptive immune system at the primary activation site – the draining LN – is fairly out of focus. Data for the amount and spatial allocation of immune cells and their descendants in tumor draining LNs reflecting tumorous immunomodulatory transformations are rare and not matched with tumor infiltrating immune cells[17,18,19,20,21]

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Results

Conclusion