ACTA1 and neoplasm: In line with our data, the authors reported reduced SPARC, collagen and α-SMA immunoreactivity in nanometastases, micrometastases and millimetastases.39 Although α-SMA staining was not performed for matched human metastases and primary tumours, the authors found that macrometastases became increasingly more desmoplastic and eventually recapitulated the primary tumour.39 In our study, we randomly used liver metastases for LC-MS/MS analysis but did not categorise lesions in several subgroups.