Analysis of the expression of CAF related proteins based on molecular subtype of each metastatic site revealed that stromal S100A4 (p = 0.015) and tumoral PDGFRα (p = 0.037) was associated with bone metastasis, tumoral prolyl 4-hydroxylase (p = 0.003) and tumoral S100A4 (p = 0.034) with brain metastasis, stromal podoplanin (p = 0.019) and tumoral S100A4 (p = 0.019) with liver metastasis, and tumoral PDGFRα (p = 0.034) and stromal PDGFRα (p = 0.042) with lung metastasis (Additional file 1: Table S3). The gene discussed is S100A4; the disease is bone metastasis.