Table 1. Demographic, baseline disease, and treatment characteristics for the entire cohort (n=62) and broken down by whether or not patients received adjuvant therapy following surgical resection.

Characteristic	All patients (n=62)	Patients who received adjuvant therapy (n=39)	Patients who did not receive adjuvant therapy (n=23)	P value
Demographic data
Age: median [IQR]	68 [57-77]	67 [55-76]	68 [65-80]	0.107
Age ≥65 years: No. (%)	38 [61]	21 [54]	17 [74]	0.177
Gender: No. male (%)	35 [56]	23 [59]	12 [52]	0.791
ECOG performance status ≥1: No. (%)	13 [21]	10 [26]	3 [13]	0.338
Tumor resection specimen data
Tumor diameter: median centimeters (IQR)	4.0 (3.0-6.0)	4.5 (3.5-6.0)	4.0 (3.0-6.3)	0.645
Tumor diameter: No. >3 cm [%]	45 [73]	30 [77]	15 [65]	0.383
Histologic grade
No. well differentiated [%]	0 [0]	0 [0]	0 [0]	–
No. moderately differentiated [%]	11 [18]	6 [15]	5 [22]	0.732
No. poorly differentiated [%]	51 [82]	33 [85]	18 [78]	0.732
Tumor stage
No. T2 [%]	10 [16]	7 [18]	3 [13]	0.731
No. T3 [%]	41 [66]	24 [62]	17 [73]	0.409
No. T4 [%]	11 [18]	8 [21]	3 [13]	0.516
Lymph node involvement at resection: No. [%]	48 [77]	31 [79]	17 [74]	0.755
Positive margin at resection: No. [%]	18 [29]	11 [28]	7 [30]	0.999
Lymphovascular invasion present: No. [%]	46 [74]	28 [72]	18 [78]	0.765
Perineural invasion present: No. [%]	52 [84]	31 [79]	21 [54]	0.298

The right-most column shows P values for statistical comparison of each characteristic between patients who did (n=39) and did not (n=23) receive adjuvant therapy in the form of chemoradiation or chemotherapy alone. IQR, interquartile range; No., number; ECOG, Eastern Cooperative Oncology Group; cGy, centiGray.