Sphincter-saving operations have become the treatment of choice for cancers of the lower thirds of the rectum. Any effort to ensure the safety of these procedures is commendable.
Aim: the aim of the present study is to evaluate the role of intra-operative frozen section in the management of cancers of the extraperitoneal rectum by restorative resection.
Patients & methods: 12 patients with operable middle & lower thirds rectal cancers were included in the present study. Sphincter preservation and restoration of bowel continuity after total mesorectal excision was attempted in all patients. Frozen section of the distal resection margin was performed prior to restoration of bowel continuity.
Results: In 9 patients the distal safety margin was 2 centimeters or more. In 7 of these patients, the distal resection margin was free of malignancy and intestinal continuity was restored. In 2 patients, the 2 centimeters distal resection margin was positive for malignancy. An extra-centimeter was taken which proved to be negative for malignancy thus allowing for restoration of bowel continuity in both petients. In the remaining 3 patients, the distal safety margin was 1 centimeter. In 1 of these patients, frozen section revealed that the distal resection margin was infiltrated by malignancy. In this patient, low anterior resection was abandoned in favour of abdominoperineal resection.
Conclusion: Frozen section has saved 3 patients from leaving residual tumour behind and thus from possible recurrence. Furthermore, frozen section has altered the therapeutic approach in 1 patient. Based upon these findings, it is felt that frozen section is highly indicated in all patients undergoing restorative resection especially when a distal resection margin of only 1 centimeter could be achieved.