Table 2.

Patients' characteristics.

Characteristics	Patients, n (%)
Age (year): mean: 69 ± 9, median: 69 (range: 36–112)
Sex
Male	316 (67)
Female	156 (33)
Histology
Adenocarcinoma	317 (67)
Squamous cell carcinoma	155 (33)
TNM
T1	159 (34)
T2	194 (41)
T3	79 (17)
T4	40 (8)
N0	259 (55)
N1	94 (20)
N2	103 (22)
N3	16 (3)
M0	472 (100)
Stage ∗
I	193 (41)
Ia	115 (24)
Ib	78 (17)
II	116 (25)
IIa	66 (14)
IIb	50 (11)
III	163 (34)
IIIa	129 (27)
IIIb	34 (7)

^∗The stage was clinically assessed in 97 patients (20%), while in the remaining 375 cases (80%), it was pathologically assessed.