Colorectal cancer patients with invasive tumors had significantly lower recurrence rates after radical resection, compared with local excision, based on data from a review of approximately 500 patients.
Minimally invasive treatment is becoming more widely used for colorectal cancer, but the risk of incomplete excision is a concern.
To compare long-term outcomes of radical resection vs. local excision for patients with invasive and noninvasive colorectal cancer, the study population included 52 patients with noninvasive intramucosal colorectal cancer and 467 patients with invasive T1 colorectal cancer.
Radical resection was performed in 75% of the patients with invasive T1 tumors; local excision was performed in 25%. Radical resection was performed significantly more often for proximal lesions, compared with rectal lesions.
After a minimum follow-up period of 5 years, significantly fewer T1 patients who underwent radical resection had recurrence, compared with patients who underwent local excision (3% vs. 13%, respectively).
In addition, 5-year overall survival and disease-free survival were significantly better in T1 patients who were treated with radical resection vs. local excision, with hazard ratios of 1.42 and 1.62, respectively, These differences in survival rates remained significant after controlling for age, sex, and comorbidities.
Tumor budding and rectal location were significantly associated with recurrent disease, whereas tumor grade and the presence of submucosal or angiolymphatic invasion were not.
Among the 52 patients with noninvasive intramucosal colorectal cancer, 54% were treated with local excision and 46% were treated with radical resection. Disease-free survival was 100% in these patients, regardless of treatment type. No significant differences were found in overall survival rates between the two treatment groups.
The study was limited by a lack of randomization of the patients to local excision or radical resection. Additional research is needed to better identify colorectal cancer patients with T1 tumors who can be treated effectively with local excision, he noted.