EGF and squamous cell lung carcinoma: The increase in epidermal growth factor in particular and, likely other factors related to wound healing result in an increased likelihood that circulating tumor cells will form a macro-metastatic lesion at the site of the wound, particularly in the case of malignant cells harboring increased numbers of EGFR, as is the case with squamous cell carcinoma of the lung. Other wound-healing factors are likely involved as well.