Supplemental Table 1. Pathological result of dissected paratracheal lymph node in patients with initial negative paratracheal LNs involvement Pathological metastasis Lymph node Total number of dissection Positive Negative 2R 7 1 6 2L 3 0 3 4R

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Supplemental Table 1. Pathological result of dissected paratracheal lymph node in patients with initial negative paratracheal LNs involvement

Pathological metastasis Lymph node Total number

of dissection Positive Negative

2R 7 1 6

2L 3 0 3

4R ⁸⁹ ⁵ ⁸⁴

4L 12 0 12

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Table 1. Continued from previous page

EGJ, esophagogastric junction; SUVmax, maximum standardized uptake value.

Initial Paratracheal LNs involvement Clinical feature Positive

73 (6.1%)

Negative

1,126 (93.9%) p Tumor length (min,max) 7 cm (2, 16) 4 cm (0.5, 19) <0.001 Distance from tumor’s proximal edge

to EGJ (min,max) 7 cm (0, 23) 4 cm (‐4, 21) <0.001

Primary SUVmax, median (min,max) 12.05 (0, 59.8) 8.45 (0, 58) <0.001

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Table 2. Clinical characteristics of patients with and without paratracheal LNs recurrence (n=1,071)

Paratracheal LNs recurrence Clinical feature Positive

70 (6.5%)

Negative

1,001 (93.5%) p

Median age (range) 60 (35, 80) 63 (20,91) 0.01

Sex 0.70

Male 61 (6.4) 887 (93.6)

Female 9 (7.3) 114 (92.7)

Location of tumor 0.12

Esophagus 7 (10.6) 59 (89.4)

Siewert type I 33 (6.9) 446 (93.1)

Siewert type II 29 (6.4) 421 (93.6)

Siewert type III 1 (1.3) 75 (98.7)

Tumor differentiation 0.04

Well differentiated 0 (0) 13 (100)

Moderately differentiated 26 (5.2) 478 (94.8)

Poorly differentiated 44 (8.3) 484 (91.7)

Undetermined 0 (0) 26 (100)

Signet ring cell carcinoma 0.99

Yes 10 (6.1) 155 (93.9)

No 60 (6.6) 846 (93.4)

Baseline T category <0.001

T1 6 (2.9) 200 (97.1)

T2 1 (0.9) 103 (99.1)

T3 63 (8.5) 681 (91.5)

T4 0 (0) 17 (100)

Baseline N category <0.001

N0 24 (4.2) 541 (95.8)

N1 37 (9.5) 352 (90.5)

N2 7 (7.4) 87 (92.6)

N3 2 (9.5) 21 (90.5)

Baseline clinical stage <0.001

I 6 (2.9) 202 (97.1)

IIA 0 (0) 5 (100)

IIB 1 (1.1) 90 (98.9)

III 54 (8.1) 615 (91.9)

IVA 9 (9.2) 89 (90.8)

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Table 2. Continued from previous page

Paratracheal LNs recurrence Clinical feature Positive

70 (6.5%)

Negative

1,001 (93.5%) p

Tumor length (range) 5 cm (1, 19) 4 cm (0.5, 18) 0.02

Distance from tumor’s proximal edge

to EGJ (min,max) 4 cm (0, 17) 4 cm (‐4, 20) 0.04

Primary SUVmax, median (min,max) 9.8 (0, 24.5) 8.1 (0, 58) 0.12 EGJ, esophagogastric junction; SUVmax, maximum standardized uptake value.

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Table 3. Univariate and multivariable logistic regression models for paratracheal LNs recurrence

Univariate Multivariable

Clinical feature OR (95% CI) p OR (95% CI) p

Age^a 0.98 (0.96-1.00) 0.03 0.98 (0.96‐1.00) 0.13

Sex

Male 1 (reference)

Female 1.15 (0.56-2.37) 0.71

Location of tumor

Esophagus 1 (reference)

Siewert type I 0.62 (0.26‐1.48) 0.28 Siewert type II 0.58 (0.25-1.38) 0.22 Siewert type III 0.11 (0.01‐0.93) 0.04

Tumor length^a 1.11 (1.03-1.2) 0.01 0.94 (0.82‐1.08) 0.36 Distance from tumor’s

proximal edge to EGJ^a 1.10 (1.02-1.19) 0.02 1.09 (0.96‐1.22) 0.15 Tumor differentiation

Well/moderate 1 (reference) 1 (reference)

Poor 1.72 (1.03-2.86) 0.03 1.8 (1.00‐3.25) 0.05

Signet ring cell carcinoma

No 1 (reference)

Yes 0.91 (0.46-1.81) 0.79

Baseline T category

T1/2 1 (reference) 1 (reference)

T3/T4 3.91 (1.78-8.56) <0.001 5.10 (1.46‐17.89) 0.01 Baseline N category

N0 1 (reference) 1 (reference)

N1/N2/N3 2.25 (1.35-3.75) 0.002 1.53 (0.82‐2.88) 0.18 Baseline clinical stage

I/IIA/IIB 1 (reference)

III/IVA 3.8 (1.73-8.32) 0.001

SUVmaxa 1.00 (0.98-1.02) 0.81

EGJ, esophagogastric junction; SUVmax, maximum standardized uptake value; OR, odds ratio; CI, confidence interval.

aContinuous variable.

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Supplemental Table 1. Univariate and multivariable Cox regression models for over-all survival in 1199 patients

Univariate Multivariable

Clinical feature HR (95% CI) p HR (95% CI) p

Age^a 1.14 (1.07‐1.23) <.001 1.17 (1.07‐1.28) <.001 Sex

Male 1 (reference)

Female 0.77 (0.6‐1) 0.05 0.86 (0.61‐1.22) 0.40

Location of tumor

Esophagus 1 (reference)

Siewert type I 1.13 (0.85‐1.51) 0.40 Siewert type II 0.77 (0.57‐1.03) 0.08 Siewert type III 0.88 (0.59‐1.31) 0.52

Tumor length^a 1.11 (1.08‐1.13) <.001 1.05 (1.01‐1.1) 0.01 Distance from tumor’s

proximal edge to EGJ^a 1.07 (1.04‐1.09) <.001 1.02 (0.98‐1.06) 0.32 Tumor differentiation

Well/moderate 1 (reference)

Poor 1.85 (1.58‐2.16) <.001 1.66 (1.35‐2.03) <.001 Signet ring cell carcinoma

No 1 (reference)

Yes 1.39 (1.14‐1.7) 0.001 0.99 (0.77‐1.27) 0.93

Baseline T category

T1/2 1 (reference)

T3/T4 2.59 (2.12‐3.15) <.001

Baseline N category

N0 1 (reference)

N1/N2/N3 2.15 (1.84‐2.51) <.001 Baseline clinical stage

I/IIA/IIB 1 (reference)

III/IVA 2.72 (2.22‐3.33) <.001 Paratracheal LNs initial

involvement

Negative 1 (reference)

Positive 1.99 (1.49‐2.66) <.001 1.46 (1.04‐2.03) 0.03 SUVmaxa

1.03 (1.02‐1.03) <.001 1.02 (1.01‐1.03) <.001 SUVmax, maximum standardized uptake value; HR, hazard rate; CI, confidence interval.

aContinuous variable.

Age variable is divided by 10 and each unit increase accounts for 10 years.

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Supplemental figures

Supplemental Figure 1. The relationship between the distance from tumor’s proximal edge to EGJ and the rate of paratracheal LNs recurrence. (A) 1,071 patients without initial paratracheal LNs positivity (B) Patients with T1/T2 tumor, (C) Patients with T3/T4 tumor

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