Molecular indicators of non-sentinel node status in breast cancer determined in preoperative biopsies by multiplexed sandwich immunoassays

Precision diagnostics: moving towards protein biomarker signatures of clinical utility in cancer

Interest in precision diagnostics has been fuelled by the concept that early detection of cancer would benefit patients; that is, if detected early, more tumours should be resectable and treatment more efficacious. Serum contains massive amounts of potentially diagnostic information, and affinity proteomics has risen as an accurate approach to decipher this, to generate actionable information that should result in more precise and evidence-based options to manage cancer. To achieve this, we need to move from single to multiplex biomarkers, a so-called signature, that can provide significantly increased diagnostic accuracy. This Opinion article focuses on the progress being made in identifying protein biomarker signatures of clinical utility, using blood-based proteomics.

Molecular biomarkers screened by next-generation RNA sequencing for non-sentinel lymph node status prediction in breast cancer patients with metastatic sentinel lymph nodes

BACKGROUND

Non-sentinel lymph node (NSLN) status prediction with molecular biomarkers may make some sentinel lymph node (SLN) positive breast cancer patients avoid the axillary lymph node dissection, but the available markers remain limited.

METHODS

SLN positive patients with and without NSLN invasion were selected, and genes differentially expressed or fused in SLN metastasis were screened by next-generation RNA sequencing.

RESULTS

Six candidates (all ER/PR+, HER2-, Ki-67 <20%) with metastatic SLNs selected from 305 patients were equally categorized as NSLN negative and positive. We identified 103 specifically expressed genes in the NSLN negative group and 47 in the NSLN positive group. Among them, FABP1 (negative group) and CYP2A13 (positive group) were the only 2 protein-encoding genes with expression levels in the 8th to 10th deciles. Using a false discovery rate threshold of <0.05, 62 up-regulated genes and 98 down-regulated genes were discovered in the NSLN positive group. Furthermore, 10 gene fusions were identified in this group with the most frequently fused gene being IGLL5.

CONCLUSIONS

The biomarkers screened in present study may broaden our understanding of the mechanisms of breast cancer metastasis to the lymph nodes and contribute to the axillary surgery selection for SLN positive patients.

The positive non-sentinel status is not the main decisional factor for chemotherapy assignment in breast cancer with micrometastatic disease in the sentinel lymph node

BACKGROUND

Surgical and systemic treatment modalities for breast cancer (BC) patients with micrometastatic disease in the sentinel lymph node biopsy (SNB) are controversial. The aim of this study was to evaluate decisional factors associated with assignment of adjuvant chemotherapy (CT).

PATIENTS AND METHODS

In a retrospective multicentric European study we evaluated cases of primary BC patients who underwent SNB. Logistic regression (LR) and recursive partitioning analyses (RPA) were performed to determine factors associated with CT.

RESULTS

Of the 172 patients with micrometastatic disease, 39.5% received adjuvant CT. In the group treated with CT, patients tended to be younger (P = 0.001), with higher grade (P = 0.001) and HER2 positive tumors (P = 0.006) compared to patients without CT. In multivariate LR, age (P = 0.0027), high grading (P = 0.01) HER2 positivity (P = 0.03), and positive non-SN status (P = 0.03) were significantly associated with CT. RPA demonstrated that tumor grade, and not the non-SN status, was the first split in the partition tree followed by HER2 status, and non-SN status influencing the probability for CT administration.

CONCLUSION

High tumor grade is the main decisional factor followed by HER2 positivity and then by the positive non-SN status for CT in micrometastatic disease in the SN.