FDG uptake to reflect NLR and expression levels of TILs and PD-L1 in patients with primary breast cancer: Tumor inflammation and immunity.

Abstract

e12110 Background: 18F-Fluorodeoxyglucose-positron emission tomography(FDG-PET) is used to evaluate the glucose metabolic rates of cancers. Several studies have reported that high FDG uptake is predictive of poor prognosis and aggressive features in patients with breast cancer (BC).However, FDG-uptake is influenced by many factors, including inflammation and immunity. In this study, we investigated the relationship between FDG uptake and inflammation and immunological factors, including Neutrophil/lymphocyte ratio (NLR) and degrees of Tumor-infiltrating lymphocytes (TILs), programmed cell death ligand 1 (PD-L1). Methods: We retrospectively investigated the cases of 96 consecutive invasive ductal carcinoma patients who underwent surgery andunderwent FDG-PET preoperatively. The evaluation of PET was determined using standardized uptake value max (SUVmax). We divided the cases into two groups based on the value of SUVmax; low (<2.5) and high (≥2.5) and the value of NRL; low (<1.7) and high (≥1.7). Grade of stromal-TILs was immunohistochemically (IHC) evaluated using the criteria of the International Working Group for TILs in BC: low (10-20%), intermediate (20-40%) and high (50-90%). PD-L1 positive were evaluated by IHC. The relationships between SUVmax and NLR and expressions of TILs, PD-L1 were investigated. Results: Among the 96 patients, 52 (54.2%) had high SUVmax in the primary tumor. The multivariate analysis revealed that large tumor size (p<0.001), high nuclear grade (p=0.016), high NLR (p=0.037), and PD-L1 (p=0.003) were significantly associated with high SUVmax in the primary tumor.There were associations between SUVmax and NLR(r=0.319, p<0.001) and TILs (r=0.298, p<0.001). Among the 96 cases with, there was 4 cases (4.2%) had recurrent disease, while 3 cases among the 4 cases with recurrent disease was low TILs and the one case was high TILs and PD-L1 psitive. disease recurrence.It is interesting to note that the group with high SUVmax and low NLR had no recurrent disease. Conclusions: The present study demonstrated thatthe finding of preoperative FDG uptake in BC may be reflective of poor prognosis and high NLR and the grades of high TILs and expression of PD-L1in the tumor. From these findings, preoperative high FDG uptake in BC may be reflective of tumor microenvironmentincluding inflammatory or immunological features in addition to aggressive features among patients with BC.