Multiple colorectal polyps and risk of cancer

: The malignancy rate ("severe cellular atypia' and "invasive carcinoma' in adenomas and associated carcinoma) was determined in a retrospective study on 95 patients, aged 28 to 97 years (median age 65 years), with colonoscopy findings showing multiple (more than 8) colorectal polyps. It amounted to 22% to 100% in patients with 8 and up to more than 50 polyps in the colorectum. The malignancy rate was "only' 3.7% to 11.8% based on the number of polyps in the individual patients and thus was about the same as in patients with an isolated or few polyps. Thus, malignancy rate increases with number of polyps (by far the majority adenomas). Endoscopy showed the presence of gastric polyps in eleven of the 95 patients (11.6%) with multiple colorectal polyps. With the exception of one "borderline lesion' they were benign, showing no definite tendency towards malignancy. After endoscopic ectomy of the multiple polyps surgical treatment (procto-mucosectomy, segment resection, hemicolectomy or colectomy) was necessary in 37 patients (39%).