To substantiate the role of NBCn1-mediated Na+,HCO3–-cotransport, we therefore stratified the patient cohort from Fig. 4c into three groups based on the axillary sentinel lymph node status: the first group was without metastases, the second had lymph nodes containing isolated tumor cells (≤200 cells and ≤0.2 mm) or micrometastases (>200 cells or >0.2 mm, but <2 mm), and the third had lymph nodes containing macrometastases (≥2 mm). This evidence concerns the gene SLC4A7 and neoplasm.