Tumor stroma: a determinant role in local recurrence of rectal cancer patients receiving total mesorectal excision?

Local recurrence (LR) dramatically decreases since the adoption of total mesorectal excision (TME) but still could not be avoided. Current mainstream views try to elucidate LR by focusing on tumor cells invasion, such as tumor stage or regional lymph nodes metastasis. But we hypothesize that not tumor cells but the cancer stroma should be responsible for the LR after TME. We believed current resection range of TME may cause remnant cancer stroma, which might act as the determinant role in LR by motivating carcinogenesis of neighboring normal epithelium. A series of supportive evidences are listed and future experiments to test our hypothesis are suggested. Once this hypothesis proved, current standards of TME should be substantially rewritten concerning the resection margins.