Background: Endoscopic follow-up is advised in patients operated for colorectal cancer due to a high risk for both metachronous colorectal cancer and adenomas. Such issue has been scarcely addressed in Italy. This study aimed to evaluate the incidence of neoplastic lesions at a scheduled endoscopic follow-up and to identify the patients at higher risk of recurrence.
Methods: Colorectal cancer patients diagnosed in the three participating hospitals (one North, one Centre and one South Italy) were scheduled for colonoscopies at 1, 3 and 5 years after surgery. Incidence of adenomas, advanced adenomas and colorectal cancer was assessed in all patients. Neoplastic incidence in patients with and without synchronous lesions at entry was also compared.
Results: Overall, 318 consecutive patients were prospectively enrolled including 108 (34%, group A) with a synchronous lesion and 210 (group B) without it. A cumulative neoplastic incidence of 20.1, 32.4 and 44% was observed at 1, 3 and 5 years of follow-up, respectively. The cumulative incidence of all the lesions was 70% in group A and 30.2% in group B at 5-year follow-up, being 39.5 and 15.5% after excluding the lesions detected at 1-year examination. A neoplastic lesion was detected more frequently in group A at 1year (30.5% versus 14.7%; p = 0.0013), 3 years (21.4% versus 7.6%; p = 0.0008) and at 5years (18.1% versus 7.8%; p = 0.02).
Conclusions: Our data showed that the incidence of adenomas in patients operated for colorectal cancer is fairly high. Colorectal cancer patients with synchronous lesions are at higher risk of neoplastic recurrence at follow-up as compared to those without them.