Programmed death-ligand 1 expression in the tumour stroma of colorectal liver oligometastases and its association with prognosis after liver resection

Predicting extensive metastasis in postoperative oligometastatic colorectal cancer

PURPOSE

Oligometastatic colorectal cancer (OMCRC) patients can achieve long-term disease control with multidisciplinary treatment. However, the development of extensive metastasis worsens prognosis and restricts treatment options. This study aims to develop a predictive model for extensive metastasis in OMCRC to assist in clinical decision-making.

METHODS

Clinical and pathological data for OMCRC patients were collected from the Second Affiliated Hospital of Soochow University. Patients were randomly divided into training and testing cohorts. Risk factors for extensive metastasis were identified through LASSO regression analysis and COX regression analysis. Three predictive models were developed in the training cohort and validated in the testing cohort: COX regression analysis, Extreme Gradient Boosting (XGBoost), and Survival Support Vector Machine (SurvSVM). Finally, the optimal model was visualized with the nomogram.

RESULTS

A total of 214 patients with OMCRC were enrolled in the study. Four independent risk factors were identified: whether surgery has been undertaken following oligometastasis (WST), histological type (HT), carcinoembryonic antigen at the last follow-up (CAE at last-FU), and preoperative albumin to globulin ratio (Preop-AGR). In the testing cohort, the COX model (1-year AUC = 0.82, 3-year AUC = 0.72, 5-year AUC = 0.85, mean AUC = 0.80) performed best. Decision curve analysis (DCA) confirmed the net benefit of the Cox model, and the nomogram provided accurate predictions of metastasis risk.

CONCLUSION

CAE at last-FU, Preop-AGR, HT, and WST are independent risk factors for extensive metastasis in OMCRC. The nomogram model incorporating risk factors can assist clinicians in developing optimal treatment for OMCRC patients.

Role of stromal PD-L1 expression in colorectal liver metastasis

BACKGROUND AND AIM

The outcomes of immune checkpoint blockade for colorectal cancer (CRC) treatment are unsatisfactory. Furthermore, the efficacy of immune checkpoint blockade for liver metastasis of various cancer is poor. Here, we investigated the relationship between stromal programmed death-ligand 1 (PD-L1) expression and the prognosis of patients with colorectal cancer liver metastasis (CRLM).

METHODS

The present study enrolled 84 CRLM patients who underwent surgery (R0) for CRC. Immunohistochemistry was performed to analyze stromal PD-L1 expression in CRLM.

RESULTS

Stromal PD-L1 was expressed in 52.3% of CRLM samples, which was associated with fewer not optimally resectable metastases (p = 0.04). Stromal PD-L1 also tended to associate with a lower tumor grade (p = 0.08). Stromal PD-L1-positive patients had longer overall survival (p = 0.003). Multivariate analysis identified stromal PD-L1 expression (p = 0.008) and poorer differentiation (p < 0.001) as independent prognostic indicators. Furthermore, stromal PD-L1 expression was correlated to a high number of tumor-infiltrating lymphocytes (TILs). Stromal PD-L1- and low TIL groups had shorter OS than stromal PD-L1 + and high TIL groups (46.6% vs. 81.8%, p = 0.05) Stromal PD-L1-positive patients had longer disease-free survival (DFS) (p = 0.03) and time to surgical failure (p = 0.001). Interestingly, stromal PD-L1 expression was positively related to the desmoplastic subtype (p = 0.0002) and inversely related to the replacement subtype of the histological growth pattern (p = 0.008).

CONCLUSIONS

Stromal PD-L1 expression may be a significant prognostic marker for CRLM.

Navigating through the PD-1/PDL-1 Landscape: A Systematic Review and Meta-Analysis of Clinical Outcomes in Hepatocellular Carcinoma and Their Influence on Immunotherapy and Tumor Microenvironment

This systematic review aimed to assess the prognostic significance of programmed cell death-ligand 1 (PDL-1) and programmed cell death protein 1 (PD-1) in hepatocellular carcinoma (HCC). Medline, EMBASE, and Cochrane Library database searches were conducted, revealing nine relevant cohort studies (seven PDL-1 and three PD-1). Our meta-analysis showed that PD-1/PDL-1 was a marker of poor survival, regardless of the assessment method (PD-1 overall survival (OS): hazard ratio (HR) 2.40; 95% confidence interval (CI), 1.30–4.42; disease-free survival (DFS): HR 2.12; 95% CI, 1.45–3.10; PDL-1: OS: HR 3.61; 95% CI, 2.75–4.75; and DFS: HR 2.74; 95% CI, 2.09–3.59). Additionally, high level of PD-1/PDL-1 expression was associated with aging, multiple tumors, high alpha-fetoprotein levels, and advanced Barcelona Clinic Liver Cancer stage. This high level significantly predicted a poor prognosis for HCC, suggesting that anti-PD-1 therapy is plausible for patients with HCC. Furthermore, HIF-1 induces PD-1 expression, and PD1lowSOCS3high is associated with a better prognosis. Taken together, combination therapy may be the key to effective immunotherapy. Thus, exploring other markers, such as HIF-1 and SOCS3, along with PD-1/PDL-1 immunotherapy, may lead to improved outcomes.