Adipocyte heterogeneity and tumor infiltration of adipose tissue in patients with metastatic breast cancer.

Background: The adipose tissue may serve as a source of energy supporting cancer growth and metastasis. Our understanding of the adipocytes which compose the adipose tissue in different anatomical locations of the body as well as potential microscopic tumor infiltration in patients with metastatic breast cancer remains limited. This study therefore investigates regional variations in adipocyte size and adipose tissue tumor infiltration in patients with metastatic breast cancer.

Stromal Tumor-Infiltrating Lymphocytes in Hormone Receptor-Positive/HER2 Negative Metastatic Breast Cancer.

The immune landscape of hormone receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer (HR+/HER2- mBC), the most common subtype of BC, remains understudied. This is mainly because of reduced sample acquisition opportunities from metastases as compared with primary tumors. In this study, we explored stromal tumor-infiltrating lymphocytes (sTIL) in metastatic samples collected through our post-mortem tissue donation program UZ/KU Leuven Post-mortem Tissue Donation program to Enhance Research (NCT04531696).

Rapid autopsies to enhance metastatic research: the UPTIDER post-mortem tissue donation program.

Research on metastatic cancer has been hampered by limited sample availability. Here we present the breast cancer post-mortem tissue donation program UPTIDER and show how it enabled sampling of a median of 31 (range: 5-90) metastases and 5-8 liquids per patient from its first 20 patients. In a dedicated experiment, we show the mild impact of increasing time after death on RNA quality, transcriptional profiles and immunohistochemical staining in tumor tissue samples.

Metastases of primary mixed no-special type and lobular breast cancer display an exclusive lobular histology.

Primary tumors with a mixed invasive breast carcinoma of no-special type (IBC-NST) and invasive lobular cancer (ILC) histology are present in approximately five percent of all patients with breast cancer and are understudied at the metastatic level. Here, we characterized the histology of metastases from two patients with primary mixed IBC-NST/ILC from the postmortem tissue donation program UPTIDER (NCT04531696). The 14 and 43 metastatic lesions collected at autopsy had morphological features and E-cadherin staining patterns consistent with pure ILC.