Table 2. Pathological characteristics of patients with anal canal squamous cell carcinoma treated with local excision alone (LE cohort).

Patient	Size of the tumor (cm)	Differentiation	Margin involvement by carcinoma	Lymphovascular invasion	Comment
1	0.1	Moderately differentiated	See comment	Absent	Margin could not be assessed
2	0.7	Poorly differentiated	Negative	Absent	Margins negative for invasive or in situ carcinoma, 6 mm clearance
3	0.6	Well differentiated	Negative	Absent	Margin focally involved by carcinoma—in situ
4	1.8	Well differentiated	Negative	Absent	Margin focally involved by carcinoma—in situ
5	1.0	Moderately differentiated	Positive	Absent	Invasive carcinoma present at margin on first resection, follow-up resection led to negative margins (>1 cm clearance)
6	0.2	Moderately differentiated	Negative	Absent	Margins negative for invasive or in situ carcinoma, 4 mm clearance
7	0.8	Moderately differentiated	Negative	Absent	Invasive carcinoma within 1 mm of margin
8	0.2	Well differentiated	Negative	Absent	Margins negative for in situ and invasive carcinoma, 5 mm clearance
9	0.2	Well differentiated	Negative	Absent	Margins negative for invasive carcinoma, but carcinoma in situ present at edges of tissue fragments—unclear whether this represents true margin (specimen fragmented). In situ carcinoma at margin could not be excluded
10	1.2	Well differentiated	Positive	Absent	Invasive carcinoma transected at deep and lateral margins
11	0.1, 2 foci	Well differentiated	Negative	Absent	Margin negative for invasive carcinoma. In situ carcinoma extends to margin
12	0.7	Well differentiated	Negative	Absent	In situ carcinoma 0.5 mm from margin
13	0.3	Poorly differentiated	Negative	Present	Margins negative for invasive or in situ carcinoma, 7 mm clearance