Liquid Biopsy in Colorectal Cancer: Quo Vadis? Implementation of Liquid Biopsies in Routine Clinical Patient Care in Two German Comprehensive Cancer Centers.

Objectives: The use of liquid biopsies (LB) in patients with solid malignancies enables comprehensive genomic profiling (CGP) of circulating tumor DNA (ctDNA) and has the potential to guide therapy stratification and support disease monitoring. To examine clinical uptake of LB in a real-world setting, LB implementation was analyzed at two German cancer centers (LMU Munich and Charité - Universitätsmedizin Berlin) between 2017 and 2021, with focus on colorectal cancer (CRC) patients. Methods: In this retrospective analysis, all patients who received a LB between January 2017 and December 2021 as part of routine clinical management were included. To provide adequate context, we collected disease characteristics and technical specifications of the LB methods applied. Additionally, we examined the concordance of RAS status in tumor tissue and LB. Finally, we discuss the potential of LB as a diagnostic tool to drive personalized treatment in CRC patients and how to implement LB in clinical routine. Results: In total, our cohort included 86 CRC patients and 161 LB conducted in these patients between 2017 and 2021. In 59 patients, comparison between tissue-based and liquid-based molecular diagnostics, revealed a divergence in 23 (39%) of the evaluable samples. Conclusion: Our real-world data analysis indicates that the possibilities of LB are not yet exploited in everyday clinical practice. Currently, the variety of methods and lack of standardization, as well as restricted reimbursement for liquid based CGP hinder the use of LB in clinical routine. To overcome these issues, prospective clinical trials are needed to provide evidence driving the implementation of LB into the management of CRC patients and to support their implementation into clinical guidelines.

Glycochenodeoxycholate Promotes Liver Fibrosis in Mice with Hepatocellular Cholestasis.

Hydrophobic bile salts are considered to promote liver fibrosis in cholestasis. However, evidence for this widely accepted hypothesis remains scarce. In established animal models of cholestasis, e.g., by Mdr2 knockout, cholestasis and fibrosis are both secondary to biliary damage. Therefore, to test the specific contribution of accumulating bile salts to liver fibrosis in cholestatic disease, we applied the unique model of inducible hepatocellular cholestasis in cholate-fed Atp8b1G308V/G308V mice. Glycochenodeoxycholate (GCDCA) was supplemented to humanize the murine bile salt pool, as confirmed by HPLC. Biomarkers of cholestasis and liver fibrosis were quantified. Hepatic stellate cells (HSC) isolated from wild-type mice were stimulated with bile salts. Proliferation, cell accumulation, and collagen deposition of HSC were determined. In cholestatic Atp8b1G308V/G308V mice, increased hepatic expression of αSMA and collagen1a mRNA and excess hepatic collagen deposition indicated development of liver fibrosis only upon GCDCA supplementation. In vitro, numbers of myofibroblasts and deposition of collagen were increased after incubation with hydrophobic but not hydrophilic bile salts, and associated with EGFR and MEK1/2 activation. We concluded that chronic hepatocellular cholestasis alone, independently of biliary damage, induces liver fibrosis in mice in presence of the human bile salt GCDCA. Bile salts may have direct pro-fibrotic effects on HSC, putatively involving EGFR and MEK1/2 signaling.

The efficacy of treatment options for patients with gastric cancer and peritoneal metastasis.

BACKGROUND: Patients with peritoneal metastases of gastric cancer have a poor prognosis and median survival of 7 months. This study compared treatment options and outcomes based on the Peritoneal Cancer Index (PCI). METHODS: This retrospective analysis included patients with gastric cancer treated between August 2008 and December 2017 with synchronous peritoneal metastases only diagnosed by laparoscopy. The three treatments were as follows: (1) cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in combination with pre- and postoperative systemic chemotherapy (n = 58), (2) laparotomy/laparoscopy without CRS, but HIPEC in combination with pre- and postoperative systemic chemotherapy (n = 11), and (3) systemic chemotherapy only (n = 19). RESULTS: A total of 88 patients aged 54.6 ± 10.9 years with mean PCI of 14.3 ± 11.3 were included. The PCI was significantly lower in group 1 (8.3 ± 5.7) than in group 2 (23.9 ± 11.1, p < 0.001) and group 3 (27.3 ± 9.3, p < 0.001). Mean time from diagnosis to laparoscopy was 5.2 ± 2.9 months. The median overall survival was 9.8 ± 0.7 for group 1, 6.3 ± 3.0 for group 2 and 4.9 ± 1.9 months for group 3 (p < 0.001). Predictors for deteriorated overall patient survival included > 4 cycles of preoperative chemotherapy (HR 4.49, p < 0.001), lymph-node metastasis (HR 3.53, p = 0.005), PCI ≥ 12 (HR 2.11, p = 0.036), and incompleteness of cytoreduction (HR 4.30, p = 0.001) in patients treated with CRS and HIPEC. CONCLUSION: CRS and HIPEC showed convincing results in selected patients with PCI < 12 and complete cytoreduction. Prolonged duration (> 4 cycles) of preoperative intravenous chemotherapy reduced patient survival in patients suitable for CRS and HIPEC.