It has been shown that cFn expression in pre-metastatic tissue is elevated and it plays an important role in the formation of pre-metastatic myeloid clusters.[16] In addition, STAT3 regulates the expression of cFn in pre-metastatic myeloid cells.[24] LN sections stained for cFn and CD68 showed that cFn is colocalized with small clusters of myeloid cells associated with anthracosis (Fig. 5C), indicating a possible role of cFn in the recruitment of myeloid cells and cluster formation in NSCLC regional uninvolved LNs. This evidence concerns the gene STAT3 and anthracosis.