Predicting tumor response after preoperative chemoradiation using clinical parameters in rectal cancer

Table 1 Patient demographics and tumor characteristics in the test and validation sets n (%)

Characteristics	Test set	Validation set
Total number of patients	249 (100)	15 (100)
Median age (yr, ranges)	55, 24-81	56, 33-74
Sex
Male	177 (71.1)	11 (73.3)
Female	72 (28.9)	4 (26.7)
Low margin from anal verge (cm)
≤ 5	187 (75.1)	12 (80)
> 5	62 (24.9)	3 (20)
Histological type
Adenocarcinoma	238 (95.6)	14 (93.3)
Mucinous	9 (3.6)	1 (6.7)
Signet ring cell	2 (0.8)	0 (0)
Surgery
Abdominal-perineal resection	37 (14.9)	0 (0)
Low anterior resection	208 (83.5)	14 (93.3)
Hartmann’s operation	4 (1.6)	1 (6.7)
Chemotherapy regimen1
FL group	200 (80.6)	9 (60)
Capecitabine group	48 (19.4)	6 (40)
Median interval to surgery (d, ranges)	55, 26-120	54, 41-78

¹Missing data: n = 1, test set; FL: 5-fluorouracil and leucovorin.