The significance of microscopic invasive cancer in endoscopically removed polyps of the large bowel. A clinicopathologic study of 51 cases

Abstract

A Clinicopathologic study of 51 patients with endoscopically removed large bowel polyps showing histologic evidence of malignancy, either focally, to a massive extent, or comprising the entire polyp, revealed only one absolute finding capable of predicting residual disease, namely, the presence of cancer at the resection line. Of 23 radical resections, only one was justified. This case showed evidence of residual disease in the colectomy specimen that could have been predicted on the basis of involvement of the diathermy margin by carcinoma. Of 28 patients having polypectomy alone, 1 patient developed a Dukes' B carcinoma. The polyp, removed 9 months previously from the same site, had shown involvement of the margin by carcinoma. A conservative approach is thus advocated in the absence of this finding.

Histologic Risk Factors and Clinical Outcome in Colorectal Malignant Polyp: A Pooled-Data Analysis

“…Polyp morphology was available in 19 series, enrolling 1,145 polyps. 1 [39][40][41][42] Finally, cancerrelated death was reported in 56 (3.6 percent) of those 1,535 patients for whom follow-up data were available, with an interval from the diagnosis ranging from 5 to 101 (median, 32) months. Death because of surgical complications, inferred from 28 studies, was reported in 8 (0.8 percent) of 951 operated patients.…”

“…1 Its prevalence has been steadily rising during the past decades-mainly because of the widespread use of colonoscopy and the improvement of polypectomy techniques-accounting for as much as 11 percent of all endoscopically removed polyps. 2,3 In clinical practice, malignant polyps often are an unexpected histologic finding that leaves both patient and physician with the understandable emotional reaction of a diagnosis of malignancy, despite an apparent radical polypectomy.…”

The malignant adenoma: when to operate and when to watch

“…Completeness and margin of excision It is widely accepted that an incomplete, or positive, resection margin is associated with an unfavourable outcome [6,16,19,[23][24][25][26][27]. To examine the importance of resection margin Hassan et al reviewed 20 studies, including a total of 980 polyps, and found that residual disease, recurrent disease, haematogenous metastases and mortality were all significantly more frequent in patients with incomplete or positive resection margins [6].…”

“…Other factors The importance of avoiding the fragmentary and piecemeal removal of polyps has been emphasised as it leads to difficulty in orientation, sectioning and confirmation that the excision has been adequate [17,25]. In one study reviewing 70 malignant polyps, incomplete and/ or badly fragmented polypectomy was an independent risk factor for adverse outcome [26].…”

Pathology of Staging of Early Colorectal Lesions During Surveillance Programmes

“…The latter includes loss of cell polarity or nuclear stratification, markedly enlarged nuclei with a dispersed chromatin pattern and a prominent nucleolus, abundant mitotic figures with atypical mitoses and prominent apoptosis. A malignant colorectal polyp is a lesion in which cancer has invaded through the muscularis mucosae and into the submucosa (Cooper, 1983;Cooper et al, 1995;Lipper et al, 1983;Morson et al, 1984;Volk et al, 1995) and T1 adenocarcinoma is defined as invasion into the submucosa and not into the muscularis propria (Edge et al, 2010). The incidence of malignant colonic polyps amongst all removed colonic adenomas varies between 2.6% and 9.7%, with an average incidence of 4.7% (Coverlizza et al, 1989).…”