Post Colectomy and Post Fixation Margin Measurement Correction Factor

This study evaluated the shrinkage of surgical margins in colorectal specimens prior to resection and at final examination and established a correction factor to ensure a sufficient resection margin. The proximal and distal surgical margins in normal anatomic positions were measured in patients with colorectal cancer prior to resection during surgery. Fresh specimens were sent to the pathology laboratory, and the distance of the tumor to the proximal and distal margins were measured before formalin fixation and after 24 h formalin fixation. The mean proximal surgical margins prior to resection, after resection, at 24 h after fixation, and after a histopathological examination were 19.8 (SD7.1) cm, 17 (SD7.5) cm, 14 (SD5.6) cm, and 13. 6 (SD5.3) cm, respectively. The values for the distal surgical margin were 12 (SD10.9) cm, 10.3 (SD9) cm, 7. 9 (SD7.7) cm and 7.7 (SD6.4) cm in respective order. The correction factor calculated for the proximal and distal resection margins prior to resection and after the final pathological examination were 1.45 and 1.55, respectively. It would be beneficial to establish and make use of correction factors when predicting shrinkages in surgical margins in curative colorectal cancer surgery.