The risk of lymph node metastasis in colorectal polyps with invasive adenocarcinoma

Abstract

One hundred fifty-one patients with colorectal polyps containing invasive adenocarcinoma treated by resection were studied to determine the incidence of lymph node metastasis and whether lymph node metastasis was related to the depth of invasion. Other variables evaluated included size and configuration of the polyp, grade of adenocarcinoma, presence or absence of lymphovascular invasion, and degree of differentiation. In patients with sessile polyps, the incidence of lymph node metastasis was 10 percent. Eighty percent of these lesions had lymphovascular invasion. For pedunculated polyps, the overall incidence of lymph node metastasis was 6 percent. However, there was no incidence of lymph node metastasis when the depth of invasion was limited to the head, neck, and stalk of the polyp (Levels 1, 2, and 3). Only when the depth of invasion reached to the base of the stalk (Level 4) was the risk of lymph node metastasis high (27 percent). The other risk factors were not associated with lymph node metastasis. We concluded that the most significant risk factor for lymph node metastasis in patients with invasive carcinoma in a polyp was invasion into the submucosa of the bowel wall (Level 4).

Analysis of pathological risk factors for lymph node metastasis of submucosal invasive colon cancer

“…Many investigators 1,2,5,6,11 agree that the depth of a submucosal invasion is an important risk factor for lymph node metastasis. We estimated the depth, width, and area of submucosal invasion as an index of the degree of submucosal invasion.…”

“…Although our data trends were similar, these factors did not show statistical significance in our study. Moreover, many investigators [3][4][5][6][7][8][9][10][11][12][13][14][15] list mucinous adenocarcinoma as a Risk of metastasis of submucosal colon cancer Y Egashira et al risk factor for lymph node metastasis. In this study, mucinous adenocarcinoma was considered as two types, one composed of undifferentiated nontubular carcinoma (signet ring cell carcinoma in the majority) and one composed of differentiated tubular adenocarcinoma.…”

“…Thus, pathologists are increasingly encountering submucosal invasive colorectal carcinomas, which are endoscopically resected. Since 10% or less of cases of submucosal invasive cancer had metastasized to the lymph nodes according to previous reports, [1][2][3][4][5][6][7] additional surgical resection of the colorectum after endoscopic resection of submucosal invasive cancer is needed for curative treatment. However, there are currently no universally accepted indications and criteria for additional surgical resection of the colorectum after endoscopic resection of submucosal invasive cancer.…”

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

“…In 23 series, [14][15][16][17][18][19][20][21][22][24][25][26][27]29,[31][32][33][34][35]38,[40][41][42] clinical or endoscopic follow-up data were available, ranging from 12 to 90 (median, 60) months, and accounting for 1,535 (80.1 percent) of the included polyps. Regarding endoscopic data, polyp site was clearly specified in 17 series, accounting for 1,461 polyps.…”

“…Regarding endoscopic data, polyp site was clearly specified in 17 series, accounting for 1,461 polyps. 14,[20][21][22]24,26,27,29,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]39 In such studies, the rectum was involved in 19.6 percent of the cases, the left colon in 71 percent, and the right colon in the remaining 9.4 percent. Polyp morphology was available in 19 series, enrolling 1,145 polyps.…”