Clinical outcome is unlinked to injection of adipose-derived regenerative cells in the axilla of breast cancer-related lymphedema patients
Background: Injection of autologous adipose-derived regenerative cells (ADRCs) combined with lipotransfer has been suggested to alleviate symptoms in diseases including breast cancer-related lymphedema (BCRL). We recently performed a randomized controlled trial injecting lipoaspirate with ADRCs into the axilla of BCRL patients, and here we aimed in the intervention group to define in an unbiased fashion whether ADRC injection was linked to the clinical outcome. Results: Unbiased multifactorial analysis ranked and defined the clinical outcomes (Sf36 physical change, L-Dex Lymph Change, ICG mdanderson change) with the highest effect on BRCL patients. The 10 patients with the highest- and lowest effect (five responders and five non-responders) were included in the study. No difference between non-responders and responders were observed for injected ADRC number/size/viability (p>0.05). In scRNAseq, we did not find any major difference (p>0.05) between groups in ADRC composition regarding adipose derived stem cells, endothelial-, smooth muscle-, T-, B-, mast cells as well as macrophages, which was verified by flow cytometry. Differential subcluster gene expression between groups were for 92.5% of genes below the threshold of 1.5, and thus neglible. Together this suggested that the ADRC phenotype was indistinguishable between BRCL responders and non-responders to the intervention. Overall design: 39 BCRL patients received lipotransfer assisted with autologous ADRCs (4.20x107 ± 1.75x107 cells) whereas 41 BCRL patients were included for placebo treatment. At 12 month follow-up, we assessed quality of life, lymphangiography, and bioimpedance enclosing 59 outcome parameters. Multifactorial analysis of clinical outcomes was used to define responders and non-responders to the intervention, and collected ADRCs from these patient groups were analyzed by single cell RNA sequencing (scRNAseq).