Table 1 A list of collected demographic and pathological data at enrollment

At tentative enrollment:

   - Age at surgery

   - Gender

Male, Female

   - Date of surgery

   - Tumor location

C, A, T, D, S, RS

   - Scope of LN dissection*

D3, D2, D1, D0

   - Surgical approach

Open surgery, Laparoscopic surgery

   - Interval between bowel resection and storage at freezer

<1 hour, 1–3 hours, > 3 hours

At final enrollment:

   - Histological type*

pap, tub1, tub2, por1/por2, muc, sig

   - Depth of tumor invasion

T1, T2, T3, T4a, T4b

   - Lymphatic invasion*

ly0, ly1, ly2, ly3

   - Venous invasion*

v0, v1, v2, v3

   - No. of LN examined

   - No. of metastatic LN

   - Degree of LN metastasis*

N1, N2, N3