The cancer rate among patients who were treated surgically for polyps that were impossible to remove endoscopically

This study aimed to determine the rate of cancer cases in patients with polyps that were removed surgically. Factors that predict the presence of cancer in these polyps were also investigated. The results confirm the fact that the best therapeutic option for polyps that cannot be removed endoscopically is radical surgery.

Polyps are abnormal growths of tissue on the inner lining of the colon that can become cancerous.  Colonoscopy (endoscopic examination of the large bowel using an instrument fitted with a video camera) has an established role in the early detection of colorectal cancer and removal of polyps. For polyps that cannot be removed endoscopically, a surgery called a 'partial colectomy' (removal of a part of the large bowel) is indicated to prevent malignant (cancerous) transformation or to remove already present cancer.

This study included 750 patients from 4 hospitals, who had colectomies within the past 18 years. The mean age of the patients was 70, only 8% of them being younger than 55. Men represented 55% of the participants.

Results showed that over 70% of discovered polyps were on the right side of the large bowel and the majority were larger than 2 cm. Biopsies (taking samples of tissue from the suspicious polyp to check for cancer) taken before surgery revealed that about half of the polyps had low-grade dysplasia (slight abnormalities that suggest a risk of cancer transformation) while the rest had various other pathological changes. Analysis performed after surgery revealed that almost 18% of patients actually had invasive cancer.  The presence of high-grade dysplasia (advanced pathological abnormalities) and location on the left side of the colon were found to be risk factors for invasive cancer.

In conclusion, there was a cancer rate of 18% that could not be predicted based on the pre-surgical evaluation. Given this fact, radical surgery should be considered for all patients with polyps that cannot be removed endoscopically.