Lack of association between SLFN11 expression and treatment efficacy or survival outcomes in patients with pancreatic ductal adenocarcinoma.

Purpose: Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis. Despite the use of aggressive combination chemotherapy regimens, outcomes remain unsatisfactory. Schlafen family member 11 (SLFN11) has been reported to regulate the DNA damage response and influence tumor sensitivity to certain chemotherapeutic agents. This study aimed to investigate the expression of SLFN11 in PDAC and its potential as a biomarker for predicting treatment efficacy and survival outcomes.

Methods: This retrospective observational cohort study included 158 patients with unresectable or borderline resectable PDAC who received palliative chemotherapy. Patients were classified into three groups: metastatic, locally advanced, and borderline resectable PDAC. Immunohistochemical staining for SLFN11 was performed on biopsy specimens, and expression levels were quantified using the histo-score (H-score). Associations between SLFN11 expression and clinical outcomes, including progression-free survival and overall survival, were analyzed using Kaplan-Meier methods and Cox regression models.

Results: SLFN11 expression was observed in 54.4% of PDAC tissues. The median H-score for SLFN11 expression was higher in metastatic cases than in locally advanced and borderline resectable cases. However, no significant association was found between SLFN11 expression and the efficacy of chemotherapy or clinical outcomes.

Conclusion: Despite the hypothesized role of SLFN11 as a predictive biomarker for chemotherapy efficacy, no significant association was found between SLFN11 expression and clinical outcomes in PDAC. Further studies with larger cohorts and more detailed staging are needed to clarify the potential utility of SLFN11 as a therapeutic biomarker in PDAC.