Table 1 Demographic and clinico-pathological characteristics of included patients and pathological tumor characteristics

Sex^a

 Female

3 (20%)

 Male

12 (80%)

Age at operation^b

73 (65–78)

Clavien-Dindo ≥ IIIb^a

5 (33%)

Post-operative mortality^a

3 (20%)

DA on adenoma^a

3 (20%)

Portion of duodenum involved^a

 I

1 (7%)

 II

13 (86%)

 III

1 (7%)

 IV

0 (0%)

TNM staging 7th edition

 T^a

1–2

2 (13%)

3–4

13 (87%)

N^a

 0

7 (47%)

 1

2 (13%)

 2

6 (40%)

Stage grouping 7th edition^a

 I

2 (13%)

 II

5 (34%)

 III

8 (53%)

Histological grade (G)^a

 1–2

7 (46%)

 3–4

8 (54%)

Resection status (R)^a

 0, n (%)

14 (93%)

 1, n (%)

1 (7%)

 2, n (%)

0 (0%)

n° of retrieved lymph nodes^b

23 (14–28)

n° of positive lymph nodes^b

2 (0–3)

Lymph node ratio^b

0.689 (0–0.115)

Perineural invasion^a

5 (33%)

Lymphovascular invasion^a

5 (33%)

Adjuvant chemotherapy^a

6 (40%)

Adjuvant radiotherapy^a

0 (0%)

Disease recurrence^a

3 (20%)

Disease related death^a

3 (20%)