RE: Receptor Conversion in Distant Breast Cancer Metastases: A Systematic Review and Meta-analysis

We read with interest the systematic review and meta-analysis by Schrijver et al. on receptor conversion during breast cancer progression to metastatic disease, when compared with the primary tumor (1). While we agree with the conclusions of the study, we would like to express our concerns regarding the chosen methodology, namely the exclusion of studies that relied on cytology for the assessment of receptor changes.

https://ift.tt/2GAwtKN