Risk factors of rectal cancer local recurrence: population-based survey and validation of the Swedish rectal cancer registry

Aim Despite advances in rectal cancer treatment, local recurrence (LR) remains a significant problem. To select high-risk patients for different treatment options aimed at reducing LR, it is essential to identify LR risk factors. Method Local recurrence and survival rates of 4153 patients registered 1995-1997 in the Swedish Rectal Cancer Registry were analysed. LR risk factors were analysed by multivariate methods. For LR patients the registry was validated and additional data retrieved. Results The 5-year overall and cancer-specific survival rates were 45% and 62% respectively. LR was registered in 326 (8%) patients. After R0-resections for tumours in TNM stages I-III, LR developed in 10% of tumours at 0-5 cm, 8% at 6-10 cm and 6% at 11-15 cm above the anal verge. Preoperative radiotherapy (RT) reduced the LR rate irrespective of height [0-5 cm: OR 0.50 (0.30-0.83), 6-10 cm: OR 0.42 (0.25-0.71), and 11-15 cm: OR 0.29 (0.13-0.64)]. Patients without preoperative RT had significantly higher LR risk after rectal perforation [OR 2.50 (1.48-4.24)], and almost significantly decreased LR risk when rectal washout was performed [OR 0.65 (0.43-1.00)]. Preoperative RT prolonged time to LR but did not significantly influence the survival among LR patients. LR was an isolated tumour manifestation in 103 (39%) patients with validated LR. Conclusion Preoperative RT should be considered for rectal cancer also in the upper third of the rectum. Intraoperative perforation should be avoided, and rectal washout is indicated as valuable. Follow-up for the detection of isolated LR is important. Extended follow up should be considered for patients treated with RT.