Evaluation of human epididymal secretory protein 4 expression according to the molecular subtypes (luminal A, luminal B, human epidermal growth factor receptor 2-positive, triple-negative) of breast cancer.

BACKGROUND/AIMS: Human epididymal secretory protein 4 (HE4) is originally described as an epididymis-specific protein but more recently suggested to be a putative serum tumor marker for some tumors, including breast carcinomas. In this study, we aimed to investigate the interactions between HE4 expression and molecular subtypes of breast carcinomas.

METHODS

HE4 expressions were studied in 242 formalin-fixed, paraffin-embedded breast carcinoma specimens and their association with different pathological and clinical parameters was evaluated.

RESULTS

Immunohistochemical (IHC) staining for HE4 was negative in 3 (1.2%) cases, weakly positive (1+) in 7 (2.9%) cases, moderately positive (2+) in 58 (24.0%) cases, and strongly positive (3+) in 174 (71.9%) cases. A correlation between IHC HE4 staining grade and molecular groups was detected (P = 0.005). Furthermore, it was found that HE4 expression was strongly associated with histological tumor grade, c-erbB2 expression, and positive fluorescence in situ hybridization test results that detect human epidermal growth factor receptor 2 (HER2)/neu amplification (P = 0.022, P = 0.014, and P = 0.011).

CONCLUSION

This study showed that HE4 expression is associated with HER2/neu amplification in breast cancers. These results may be commented as HE4 expression rises in patients with HER2/neu amplification. As is known, HER2/neu amplification is a poor diagnostic factor in breast cancer and HE4 expression is possibly associated with poor prognosis.