Potential of AKT2 expression as a predictor of lymph-node metastasis in invasive breast carcinoma of no special type

Abstract

Background: Invasive breast carcinoma of no special type (IBC-NST) is the most common type of breast cancer and mainly causes regional lymph-node metastasis (LNM). We investigated the potential for AKT2 expression as a predictive biomarker for LNM in IBC-NST.

Methods: Forty-eight paraffin blocks containing IBC-NST primary tumors were divided into two groups based on presence or absence of LNM. Age, tumor grade, tumor size, lymphovascular invasion (LVI), and AKT expression were assessed. AKT2 expression was assessed based on immunohistochemical staining, while other data were collected from archives.

Results: Multiple logistic regression results showed that AKT2 expression and LVI were significantly associated with LNM (odds ratio [OR], 5.32; 95% confidence interval [CI], 1.42 to 19.93 and OR, 4.46; 95% CI, 1.17 to 16.97, respectively). AKT2 expression was able to discriminate against LNM (area under the receiver operating characteristic, 0.799 ± 0.063; 95% CI, 0.676 to 0.921) at an H-score cutoff of 104.62 (83.3% sensitivity, 62.5% specificity).

Conclusions: AKT2 expression has potential as a predictor of LNM in IBC-NST. The H-score cutoff for AKT2 expression can be used as a classification guide in future studies.

Keywords: AKT2; Breast neoplasms; Immunohistochemistry; Metastasis.

Fig. 1.

Immunohistochemical staining for AKT2 expression in IBC-NST tumor cells: (A) high positive, (B) positive (C) low positive, and (D) no staining. IBC-NST, invasive breast carcinoma of no special type.

Fig. 2.

Dot plot depicting the distribution of H-score between two observers over the entire sample.

Fig. 3.

Receiver operating characteristic (ROC) curve of AKT2 expression. J, Youden index; K, K-index; AUROC, area under the receiver operating characteristic; CI, confidence interval.