Current strategies for malignant pedunculated colorectal polyps

Table 1 Histopathological factors predicting risk of lymph node metastases in malignant pedunculated colorectal polyps

Histopathological factors	Risk of LNM	Management
Depth of invasion in submucosa by the primary tumor of more than 1mm (Beaton et al[2])	High	Surgery with lymph node dissection
Poorly differentiated cancers (Beaton et al[2])
Tumor budding (Beaton et al[2], Sohn et al[18], Geramizadeh et al[7], Graham et al[22])
Lymphovascular invasion (Beaton et al[2])
Depth of invasion to the base of the stalk-Level 4 Haggitt (Nivatvongs et al[17], Kimura et al[19])
Submucosal invasion into the polyp stalk (Matsuda et al[16])
Micropapillary component (Sonoo et al[26], by Verdú et al[27], Mukai et al[28])
Head invasion (Kimura et al[19])		Surgical resection with lymph node dissection in case of additional pathological risk factors
Head invasion (Kitajima et al[15], Matsuda et al[16])	Low	Endoscopic polypectomy
Depth of submucosal invasion/stalk invasion < 3000 μm (Kitajima et al[15])
Tumor size (Nivatvongs et al[17])
Grading (Nivatvongs et al[17])
Pseudoinvasion (Backes et al[13])		Confirmation of t1 colorectal cancer by a second expert pathologist

LNM: Lymph node metastases.