Discovery of escapee tumour cells—a milestone in cancer surgery

Background Complete excision of tumour is the basic principle of curative surgery and traditionally oncological en‐bloc tumour resection is a common practice. However, ironically, it is questionable whether surgery itself will cause tumour spillage. Method From January 2019 to March 2022, 133 tumour‐related operations were performed. Routine operating field toileting was performed using warm normal saline before the end of operations. A filter was connected to the suction device throughout the whole operation processes. Sediments being trapped by the filter were sent for histopathology to look for the presence of spillage tumour cells—escapee tumour (ET) cells. Results A total of 26 (19.5%) of the collected residue showed the presence of ET cells while 16 residue samples (12%) revealed the presence of atypical cells. Incomplete resection (R1, R2 resection; P = .005, B = 1.519), advanced N‐stage (N2 or N3 disease; P = .031, B = 1.510) and certain cancer type (oesophageal cancer in this study; P = .027, B = −1.567) are the statistically significant factors related to the presence of ET cells. Conclusion Tumour spillage occurs during operations. Long‐term follow‐up and larger‐scale studies are required to determine the clinical significance of the positive ET cell cases and how to prevent tumour spillage during operations in the future.