Long-term Oncologic Outcome After Transanal Endoscopic Microsurgery for Rectal Carcinoma.

BACKGROUND: Transanal endoscopic microsurgery is superior to other methods of local excision of rectal cancer, but few studies report long-term follow-up data.

OBJECTIVE: This study investigated the use of transanal endoscopic microsurgery alone as curative and compromise therapy based on long-term disease recurrence and mortality.

DESIGN: This was a retrospective review of prospectively collected data.

SETTINGS: The study was conducted at a tertiary care university medical center.

PATIENTS: The study included 133 patients treated between 1985 and 2007. There were 3 groups, including transanal endoscopic microsurgery in curative intent (low-risk rectal carcinoma, including pT1, G1/2, L0, and LX with clear margins and a minimal distance between tumor and resection margin of >1 mm (N = 64) or clear margins only (N = 18 ))) and as compromise therapy (high-risk or incompletely resected rectal carcinoma; N = 51).

MAIN OUTCOME MEASURES: Log-rank tests were used to compare overall and cancer-specific survival.

RESULTS: The median follow-up time was 8.6 years (range, 0.2-25.1 years), and a total of 131 of 133 patients (98.5%) were followed >5 years or until death. The preoperative diagnosis of carcinoma was not associated with belonging into 1 of the 3 categories. In patients with low-risk completely (>1 mm) resected carcinoma, the 5- and 10-year local recurrence rates were 6.6% and 11.6%. In patients with high-risk or incompletely resected carcinoma, the rates were 32.5% and 35.0% (p = 0.006). The 5- and 10-year cancer-specific survival rates for low-risk patients were 98.0% and 91.0% and 84.3% and 74.3% for high-risk patients (p = 0.05).

LIMITATIONS: The study was limited by its retrospective design and small subgroups.

CONCLUSIONS: The high cancer-specific survival justifies transanal endoscopic microsurgery alone as curative treatment in low-risk rectal carcinoma. Complete resection is essential to lower the risk of local recurrence. The high local recurrence rate in patients with high-risk rectal carcinoma restricts the use of TEM alone as compromise therapy.