Tumor-infiltrating neutrophil is an independent prognostic factor in pancreatic ductal adenocarcinoma.

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal malignancies. Tumor-infiltrating neutrophils (TINs) have been implicated in tumor progression and poor prognosis; however, their roles in PDAC remain unclear. TINs have been shown to granulocytic myeloid-derived suppressor cells (G-MDSCs) which inhibit adaptive immune responses and share morphological and functional features with classical neutrophils. G-MDSCs, unlike classical neutrophils, express myeloperoxidase (MPO). We evaluated the significance of TINs and MPO expression as a marker for prognosis in the PDAC.

METHODS

We retrospectively analyzed 128 patients with surgically resected PDAC. The presence of TIN was assessed on hematoxylin and eosin-stained slides and immunohistochemistry was performed for MPO.

RESULTS

TINs were identified in 61.7% of patients with PDAC. Their presence was significantly associated with worse overall survival and recurrence-free survival. After adjusting for clinicopathological variables, TIN remained an independent predictor of a poor prognosis. MPO was expressed in all TIN within PDAC, but was absent in neutrophils within benign inflammatory conditions.

CONCLUSIONS

TIN in PDAC represents an independent adverse prognostic factor and is likely to be G-MDSCs based on MPO expression. Assessing TIN and MPO status in preoperative biopsy specimens may offer valuable prognostic information and guide future therapeutic strategies for PDAC.