Evaluation of chemotherapy-associated liver injury in patients with colorectal cancer liver metastases using indocyanine green clearance testing.

BACKGROUND: Systemic chemotherapy may render initially unresectable colorectal cancer liver metastases resectable. Histopathologic examinations of resected nontumoral liver tissue revealed chemotherapy-associated liver injuries, which was recognized to impair the function of the remnant liver. We therefore evaluated whether indocyanine green (ICG) plasma clearance helps to assess chemotherapy-induced liver damage. METHODS: Data of 101 liver resections performed between 2006 and 2008 for colorectal liver metastases were analyzed for this study. Eighteen patients had liver resection without preoperative treatment, whereas 83 patients underwent neoadjuvant chemotherapy before surgery. ICG clearance was assessed by pulse densitometry before surgery. RESULTS: Comparison of ICG retention clearances demonstrated that patients pretreated with systemic chemotherapy had a significantly lower plasma disappearance rate (ICG-PDR; 19.3 ± 5.9 vs. 23.1 ± 3.8%/min; P = 0.002) and a significantly elevated ICG retention rate at 15 min (7.9 ± 6.6 vs. 3.8 ± 1.9%; P < 0.001). The percentage of subjects with an abnormal ICG-PDR (≤18%/min) was significantly higher in the pretreated group (48.2% vs. 5.6%; P = 0.001). Patients with an ICG-PDR of ≤18 had a prolonged postoperative hospital stay and experienced four times more complications in their postoperative course. CONCLUSIONS: ICG clearance helps to identify patients with impaired liver function after neoadjuvant chemotherapy and aids in the estimation of the postoperative risk of morbidity after liver resection for colorectal liver metastases.

Bacterial metabolite interference with maturation of human monocyte-derived dendritic cells.

Dendritic cells (DC), the most potent APC, are central to antimicrobial immunity. Because of evolutionary pressure, it is reasonable that pathogens have evolved strategies to also subvert this host-defense mechanism. In the present study, we describe a novel way of bacterial interference with DC maturation. The bacterial metabolite n-butyrate, which occurs physiologically in high concentrations in the gastrointestinal tract and has well-known anti-inflammatory effects, is able to prevent LPS-induced maturation of DC resulting in a reduced capability to stimulate T cells. In particular, n-butyrate prevents homotypic DC clustering, inhibits IL-12 while sparing IL-10 production, and at the molecular level, blocks NF-kappa B translocation. These results demonstrate efficient targeting of DC function by a bacterial metabolite, which might explain the particular type of immune responsiveness in the presence of this bacterial agent as exemplified in the gastrointestinal tract.