Table 1 Baseline characteristics
Demographic variable | Before matching | After matching | ||||
|---|---|---|---|---|---|---|
Non-DLI group (n = 165) n (%) | DLI group (n = 45) n (%) | P | Non-DLI group (n = 25) n (%) | DLI group (n = 25) n (%) | P | |
Sex | Â | Â | 0.622 | Â | Â | 0.765 |
 Male | 102(61.8) | 26(57.8) |  | 17(68.0) | 16(64.0) |  |
 Female | 63(38.2) | 19(42.2) |  | 8(32.0) | 9(36.0) |  |
Age(y) | Â | Â | 0.078 | Â | Â | 0.777 |
  ≤ 60 | 108(65.5) | 23(51.1) |  | 14(56.0) | 13(52.0) |  |
  > 60 | 57(34.5) | 22(48.9) |  | 11(44.0) | 12(48.0) |  |
ECOG performance status | Â | Â | 0.288 | Â | Â | 0.733 |
 0 | 133(80.6) | 33(73.3) |  | 19(76.0) | 20(80.0) |  |
 1 | 32(19.4) | 12(26.7) |  | 6(24.0) | 5(20.0) |  |
Baseline serum CEA level (ng/mL) | Â | Â | 0.629 | Â | Â | 1.000 |
  ≤ 5 | 91(55.1) | 25(55.6) |  | 16(64.0) | 16(64.0) |  |
  > 5 | 61(37.0) | 14(31.1) |  | 9(36.0) | 9(36.0) |  |
 NA | 13(7.9) | 6(13.3) |  | 0(0.0) | 0(0.0) |  |
c T Stage |  |  | 0.044 |  |  | 0.271 |
 2 | 9(5.5) | 3(6.7) |  | 0(0.0) | 2(8.0) |  |
 3 | 100(60.6) | 18(40.0) |  | 13(52.0) | 9(36.0) |  |
 4 | 56(33.9) | 24(53.3) |  | 12(48.0) | 14(56.0) |  |
c N Stage |  |  | 0.348 |  |  | 1.000 |
 0 | 6(3.6) | 4(8.9) |  | 0(0.0) | 1(4.0) |  |
 1 | 15(9.1) | 3(6.7) |  | 2(8.0) | 2(8.0) |  |
 2 | 144(87.3) | 38(84.4) |  | 23(92.0) | 22(88.0) |  |
Tumor histologic grade | Â | Â | 0.316 | Â | Â | 0.725 |
 Well/Moderate differentiated adenocarcinoma | 133(80.6) | 37(82.2) |  | 20(80.0) | 19(76.0) |  |
 Poorly differentiated / Signet ring cell cancer or mucinous /adenocarcinoma | 24(14.6) | 8(17.8) |  | 4(16.0) | 6(24.0) |  |
 Unknown differentiated adenocarcinoma | 8(4.8) | 0(0.0) |  | 1(4.0) | 0(0.0) |  |
Induction chemotherapy | Â | Â | 0.403 | Â | Â | 0.602 |
 No | 153(92.7) | 40(88.9) |  | 24(96.0) | 22(88.0) |  |
 Yes | 12(7.3) | 5(11.1) |  | 1(4.0) | 3(12.0) |  |
Concurrent chemotherapy | Â | Â | 0.175 | Â | Â | 1.000 |
 No | 1(0.6) | 1(2.2) |  | 0(0.0) | 0(0.0) |  |
 Capecitabine | 139(84.2) | 34(75.6) |  | 20(80.0) | 20(80.0) |  |
 CAPEOX | 25(15.2) | 10(22.2) |  | 5(20.0) | 5(20.0) |  |
Anterior pelvic organ invasion | Â | Â | 0.086 | Â | Â | 1.000 |
 No | 153(92.7) | 38(84.4) |  | 21(84.0) | 21(84.0) |  |
 Yes | 12(7.3) | 7(15.6) |  | 4(16.0) | 4(16.0) |  |
Consolidation chemotherapy |  |  | 0.526 |  |  | 0.382 |
 No | 113(68.5) | 28(62.2) |  | 19(76.0) | 15(60.0) |  |
 Capecitabine | 38(23.0) | 14(31.1) |  | 4(16.0) | 9(36.0) |  |
 CAPEOX | 14(8.5) | 3(6.7) |  | 2(8.0) | 1(4.0) |  |
Time interval between neoadjuvant chemoradiotherapy and surgery, median (IQR) (weeks) | 9.7(8.1–12.0) | 10.6(8.8–14.6) | 0.072 | 8.6(7.0–11.6) | 10.6(8.9–12.7) | 0.062 |
Preoperative serum CEA level (ng/mL) | Â | Â | 0.027 | Â | Â | 0.700 |
  ≤ 5 | 148(89.7) | 37(82.2) |  | 20(80.0) | 22(88.0) |  |
  > 5 | 11(6.7) | 8(17.8) |  | 5(20.0) | 3(12.0) |  |
 NA | 6(3.6) | 0(0) |  | 0(0.0) | 0(0.0) |  |
Type of surgery | Â | Â | 0.016 | Â | Â | - |
 Abdominoperineal resection | 137(83.0) | 45(100.0) |  | 25(100.0) | 25(100.0) |  |
 Low/ultralow anterior resection | 22(13.4) | 0(0.0) |  | 0(0.0) | 0(0.0) |  |
 Hartmann procedure | 1(0.6) | 0(0.0) |  | 0(0.0) | 0(0.0) |  |
 Transanal total mesorectal excision | 4(2.4) | 0(0.0) |  | 0(0.0) | 0(0.0) |  |
 Intersphincteric resection | 1(0.6) | 0(0) |  | 0(0.0) | 0(0.0) |  |
Surgical technique | Â | Â | 0.278 | Â | Â | 0.777 |
 Open surgery | 92(55.8) | 21(46.7) |  | 13(52.0) | 14(56.0) |  |
 Laparoscopic surgery | 73(44.2) | 24(53.3) |  | 12(48.0) | 11(44.0) |  |
Operation duration, median (IQR) (min) | 185(124–236) | 208(163–273) | 0.118 | 180(126.5–222.5) | 194(105–250) | 0.839 |
Intraoperative blood loss, median (IQR) (ml) | 100(50–200) | 100(50–100) | 0.257 | 100(100–150) | 100(50–100) | 0.403 |
Number of lymph nodes examined in the surgery, median (IQR) | 9(5–12) | 9(4–12) | 0.655 | 9(6.5–11) | 7(4–11.5) | 0.307 |
Lymphovascular invasiona | Â | Â | 1.000 | Â | Â | - |
 Negative | 161(97.6) | 43(95.6) |  | 25(100.0) | 25(100.0) |  |
 Positive | 3(1.8) | 1(2.2) |  | 0(0.0) | 0(0.0) |  |
 NA | 1(0.6) | 1(2.2) |  | 0(0.0) | 0(0.0) |  |
Perineural invasiona | Â | Â | 0.136 | Â | Â | 1.000 |
 Negative | 153(92.7) | 38(84.5) |  | 24(96.0) | 23(92.0) |  |
 Positive | 11(6.7) | 6(13.3) |  | 1(4.0) | 2(8.0) |  |
 NA | 1(0.6) | 1(2.2) |  | 0(0.0) | 0(0.0) |  |
Resection margin | Â | Â | 0.220 | Â | Â | 1.000 |
 R0 | 162(98.2) | 42(93.3) |  | 24(96.0) | 25(100.0) |  |
 R1 | 3(1.8) | 3(6.7) |  | 1(4.0) | 0(0.0) |  |
ypT stage | Â | Â | 0.807 | Â | Â | 0.229 |
 0 | 40(24.2) | 9(20.0) |  | 4(16.0) | 9(36.0) |  |
 1–2 | 76(46.1) | 21(46.7) |  | 16(64.0) | 11(44.0) |  |
 3–4 | 49(29.7) | 15(33.3) |  | 5(20.0) | 5(20.0) |  |
ypN stage | Â | Â | 0.928 | Â | Â | 1.000 |
 0 | 133(80.6) | 36(80.0) |  | 22(88.0) | 21(84.0) |  |
 1–2 | 32(19.4) | 9(20.0) |  | 3(12.0) | 4(16.0) |  |
Postoperative complications | Â | Â | 0.008 | Â | Â | 1.000 |
 No | 125(75.8) | 25(55.6) |  | 15(60.0) | 16(64.0) |  |
 Clavien- Dindo Grade I-II | 32(19.4) | 19(42.2) |  | 8(32.0) | 8(32.0) |  |
 Clavien- Dindo Grade III-V | 8(4.8) | 1(2.2) |  | 2(8.0) | 1(4.0) |  |
Adjuvant chemotherapy | Â | Â | 0.828 | Â | Â | 0.057 |
 No | 57(34.5) | 16(35.5) |  | 12(48.0) | 11(44.0) |  |
 Capecitabine | 27(16.4) | 9(20.0) |  | 1(4.0) | 7(28.0) |  |
 CAPEOX or mFOLFOX6 | 68(41.2) | 17(37.8) |  | 12(48.0) | 7(28.0) |  |
 NA | 13(7.9) | 3(6.7) |  | 0(0.0) | 0(0.0) |  |