Abstract 156P
Background
Recurrence and metastasis are associated with increased mortality and poor outcomes in early breast cancer (EBC) patients. To predict loco-regional recurrence or distant metastasis, various prediction models based on clinicopathological characteristics or genetic profiles have been suggested. However, most of those systems focused on the primary tumor, and prediction of recurrence in EBC is still limited. The sentinel lymph nodes (SLNs) are the first few lymph nodes into which a tumor drains and an important barrier for protecting against metastasis. Since the immune microenvironment plays a key role in tumor progressions and metastasis, evaluation of SLNs could provide not only the state of metastasis to the axillary lymph nodes but also additional information on recurrence of EBC.
Methods
In this study, we reviewed clinical data of EBC patients who had an operation with SLNs biopsy and selected patients with loco-regional recurrences or distant metastasis during the follow-up period (at least 5 years). We analyzed clinicopathological characteristics of patients and investigated immune gene expression of SLNs by using the nCounter® PanCancer Immune Profiling Panel. We further performed immunohistochemistry for the most significantly altered genes.
Results
Among 1615 cases of EBC patients, 60 cases (3.7%) revealed loco-regional recurrences or distant metastasis. A total of 24 cases (12 SLNs of patients with recurrence and matched 12 SLNs of those without recurrence) were subjected to gene expression analysis and revealed a significant decrease in the expression of 21 genes. Based on gene expression levels and fold change, we selected 6 candidate genes (CD2, BLNK, ATF2, IGF2R, CXCL16, and IFITM1). We performed immunohistochemistry in a total of 119 cases (54 SLNs of patients with recurrence and matched 65 SLNs of those without recurrence) and found CD2 and ATF2 were significantly decreased in SLNs of EBC patients with recurrence.
Conclusions
The Pattern of immune gene expression of SLNs, especially C2 and ATF2 could be an additional prognostic marker for predicting recurrences of EBC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Ajou University School of Medicine.
Disclosure
All authors have declared no conflicts of interest.