A Positive Conversion in HER2 Status Might Affect Survival after Liver Resection for Breast Cancer Metastases

To the Editor, I wish to congratulate Ercolani et al. [1] for their article in which they reviewed their experience with liver resection for metastases from breast cancer in 51 patients. They concluded that liver resection is a safe and effective treatment for metastases from breast cancer, and encouraging long-term survival can be obtained with acceptable risk in selected patients. However, the authors did not provide detailed information about the relation of immunohistochemical receptor status between primary and metastatic tumors (only seven patients’ data were available). A change of estrogen receptor, progesterone receptor, and HER2 status in distant metastases has frequently been reported. The actual incidence of this phenomenon has been debated. Recent meta-analysis including 39 studies assessing receptor conversion from primary breast tumors to paired distant breast cancer metastases showed that negative to positive conversion percentages were 21.5, 15.9, and 9.5% for estrogen receptor, progesterone receptor, and HER2 [2]. The positive conversion in HER2 status literally changes the treatment challenges in these patients favoring the use of adjuvant antiHER2 targeted armamentarium, which in turn might affect the survival.