Retrospective Study
Copyright ©The Author(s) 2022.
World J Gastrointest Oncol. Feb 15, 2022; 14(2): 511-524
Published online Feb 15, 2022. doi: 10.4251/wjgo.v14.i2.511
Table 1 Baseline characteristics of all patients with advanced esophageal cancer who received or did not receive chemotherapy
Variable
All patients (n = 29182)
Chemotherapy received (n = 21911)
No chemo received (n = 7271)
Age
Median (IQR)64 (56-73)63 (55-71)69 (59-79)
Gender
Female5126 (17.57)3569 (16.29)1557 (21.41)
Male24056 (82.43)18342 (83.71)5714 (78.59)
Race
Black2878 (9.95)1936 (8.9)942 (13.12)
Other1669 (5.77)1245 (5.72)424 (5.9)
White24389 (84.29)18574 (85.38)5815 (80.98)
Insurance type
Medicaid2415 (8.44)1752 (8.14)663 (9.36)
Medicare13412 (46.87)9263 (43.02)4149 (58.58)
Not insured1404 (4.91)959 (4.45)445 (6.28)
Other government459 (1.6)323 (1.5)136 (1.92)
Private10923 (38.17)9233 (42.88)1690 (23.86)
Income quartiles for place of residence
Less than $300003918 (13.99)2687 (12.79)1231 (17.61)
$30000-$349995362 (19.15)3942 (18.77)1420 (20.31)
$35000-$459998066 (28.81)6081 (28.95)1985 (28.39)
$46000+10652 (38.05)8297 (39.5)2355 (33.69)
Treatment site
Academic12955 (45.07)9856 (45.75)3099 (43.05)
Non-academic15786 (54.93)11686 (54.25)4100 (56.95)
Geographic location in United States
Midwest8278 (28.8)6388 (29.65)1890 (26.25)
Northeast6772 (23.56)5178 (24.04)1594 (22.14)
South9509 (33.09)6977 (32.39)2532 (35.17)
West4182 (14.55)2999 (13.92)1183 (16.43)
Residence area type
Metro22465 (80.15)16883 (80.25)5582 (79.88)
Rural641 (2.29)467 (2.22)174 (2.49)
Urban4921 (17.56)3689 (17.53)1232 (17.63)
Number of comorbidities1
022009 (75.42)17017 (77.66)4992 (68.66)
15401 (18.51)3789 (17.29)1612 (22.17)
≥ 21772 (6.07)1105 (5.04)667 (9.17)
Year of diagnosis
2004-200915715 (53.85)11588 (52.89)4127 (56.76)
2010-201413467 (46.15)10323 (47.11)3144 (43.24)
Grade2
1633 (2.77)475 (2.73)158 (2.89)
27926 (34.65)6099 (35.02)1827 (33.46)
313849 (60.54)10497 (60.28)3352 (61.38)
4467 (2.04)343 (1.97)124 (2.27)
AJCC T stage
T051 (0.32)31 (0.24)20 (0.58)
T12624 (16.26)1889 (14.86)735 (21.45)
T21751 (10.85)1442 (11.35)309 (9.02)
T37128 (44.18)6105 (48.04)1023 (29.86)
T44570 (28.33)3233 (25.44)1337 (39.03)
pIS10 (0.06)8 (0.06)2 (0.06)
AJCC N stage
Negative4983 (22.23)3562 (20.36)1421 (28.86)
Positive17435 (77.77)13933 (79.64)3502 (71.14)
Table 2 Univariate and multivariable analyses of factors associated with receipt of chemotherapy vs no chemotherapy in advanced esophageal cancer patients
Variable

Univariate

Multivariable1

n
Odds ratio (95%CI)
P value
Odds ratio (95%CI)
P value
Age291820.96 (0.95-0.96)< 0.0010.95 (0.94-0.96)< 0.001
Gender
Female51260.71 (0.67-0.76)< 0.0010.86 (0.76-0.98)0.019
Male240561 (reference)1 (reference)
Race (combined)
Black28780.64 (0.59-0.70)< 0.0010.79 (0.67-0.93)0.005
Other16690.92 (0.82-1.03)0.1481.12 (0.89-1.40)0.322
White243891 (reference)1 (reference)
Insurance type
Medicaid24150.48 (0.44-0.54)< 0.0010.52 (0.43-0.64)< 0.001
Medicare134120.41 (0.38-0.44)< 0.0010.84 (0.73-0.97)0.017
Other government4590.43 (0.35-0.53)< 0.0010.74 (0.50-1.09)0.123
Not insured14040.39 (0.35-0.45)< 0.0010.41 (0.33-0.52)< 0.001
Private109231 (reference)1 (reference)
Income quartiles for place of residence
Less than $3000039181 (reference)1 (reference)
$30000-$3499953621.27 (1.16-1.39)< 0.0011.12 (0.95-1.33)0.172
$35000-$4599980661.40 (1.29-1.53)< 0.0011.31 (1.12-1.54)0.001
$46000+106521.61 (1.49-1.75)< 0.0011.49 (1.27-1.75)< 0.001
Treatment site
Academic129551.12 (1.06-1.18)< 0.001Dropped out of the model
Non-academic157861 (reference)
Geographic location in United States
Northeast67721.28 (1.17-1.40)< 0.0011.45 (1.22-1.72)< 0.001
Midwest82781.33 (1.23-1.45)< 0.0011.43 (1.22-1.68)< 0.001
South95091.09 (1.00-1.18)0.0441.22 (1.04-1.43)0.015
West41821 (reference)1 (reference)
Residence area type
Metro224651.13 (0.94-1.34)0.185Dropped out of the model
Urban49211.12 (0.93-1.34)0.248
Rural6411 (reference)
Number of comorbidities2
154010.69 (0.65-0.74)< 0.0010.79 (0.70-0.90)< 0.001
≥ 217720.49 (0.44-0.54)< 0.0010.61 (0.50-0.74)< 0.001
0220091 (reference)1 (reference)
Year of diagnosis
2010-2014134671.17 (1.11-1.23)< 0.0011.29 (1.17-1.43)< 0.001
2004-2009157151 (reference)1 (reference)
Grade3
16331 (reference)1 (reference)
279261.11 (0.92-1.34)0.2731.08 (0.78-1.48)0.648
3138491.04 (0.87-1.25)0.6640.96 (0.70-1.31)0.786
44670.92 (0.70-1.21)0.5500.69 (0.44-1.08)0.105
AJCC T stage
pIS101.65 (0.35-7.80)0.52520075.87 (0.00-NA)0.948
T0510.64 (0.36-1.13)0.1230.63 (0.29-1.40)0.261
T126241.06 (0.96-1.18)0.2621.10 (0.96-1.27)0.181
T217511.93 (1.68-2.22)< 0.0011.87 (1.56-2.25)< 0.001
T371282.47 (2.25-2.71)< 0.0012.29 (2.03-2.59)< 0.001
T445701 (reference)1 (reference)
AJCC N stage
Positive174351.59 (1.48-1.71)< 0.0011.35 (1.20-1.52)< 0.001
Negative49831 (reference)1 (reference)
Table 3 Univariate and multivariable analysis of patient and disease factors on overall survival in advanced esophageal cancer
Variable
Univariate

Multivariable1

Hazard ratio (95%CI)
P value
Hazard ratio (95%CI)
P value
Chemotherapy
Chemotherapy received vs not received
If 0 < time ≤ 10 mo2-< 0.001-< 0.001
If time > 10 mo0.95 (0.88-1.03)0.2040.98 (0.86-1.11)0.699
Age1.01 (1.01-1.01)< 0.0011.01 (1.00-1.01)< 0.001
Gender
Female0.99 (0.96-1.02)0.4200.90 (0.86-0.95)< 0.001
Male1 (reference)1 (reference)
Race (combined)
Black1.09 (1.05-1.14)< 0.0011.02 (0.96-1.09)0.457
Other0.86 (0.82-0.91)< 0.0010.87 (0.80-0.95)0.002
White1 (reference)1 (reference)
Insurance type
Medicaid1.28 (1.22-1.34)< 0.0011.21 (1.13-1.31)< 0.001
Medicare1.30 (1.26-1.33)< 0.0011.04 (0.99-1.10)0.119
Other government1.15 (1.04-1.26)0.0060.95 (0.82-1.10)0.493
Not insured1.37 (1.29-1.45)< 0.0011.20 (1.09-1.31)< 0.001
Private1 (reference)1 (reference)
Income quartiles for place of residence
$30000-$349990.94 (0.90-0.98)0.007Dropped out of the model
$35000-$459990.93 (0.90-0.97)< 0.001
$46000+0.87 (0.83-0.90)< 0.001
Less than $300001 (reference)
Treatment site
Academic0.87 (0.85-0.89)< 0.0010.91 (0.87-0.94)< 0.001
Non-academic1 (reference)1 (reference)
Geographic location in United States
Northeast0.92 (0.89-0.96)< 0.0010.96 (0.90-1.02)0.180
Midwest1.02 (0.98-1.06)0.3401.07 (1.01-1.14)0.032
South1.03 (0.99-1.07)0.1421.05 (0.99-1.11)0.138
West1 (reference)1 (reference)
Residence area type
Metro0.93 (0.86-1.01)0.086Dropped out of the model
Urban0.95 (0.87-1.03)0.193
Rural1 (Reference)
Number of comorbidities
11.20 (1.17-1.24)< 0.0011.09 (1.04-1.14)< 0.001
≥ 21.45 (1.37-1.52)< 0.0011.16 (1.07-1.26)< 0.001
01 (reference)1 (reference)
Year of diagnosis
2010-20140.99 (0.96-1.01)0.286Dropped out of the model
2004-20091 (Reference)
Grade
21.08 (1.00-1.18)0.0651.06 (0.95-1.20)0.297
31.30 (1.20-1.41)< 0.0011.28 (1.14-1.44)< 0.001
41.30 (1.15-1.48)< 0.0011.21 (1.02-1.45)0.032
11 (reference)1 (reference)
AJCC T stage
pIS0.57 (0.30-1.09)0.0901.11 (0.46-2.66)0.821
T00.94 (0.69-1.26)0.6650.86 (0.59-1.25)0.424
T10.88 (0.84-0.93)< 0.0010.89 (0.84-0.95)< 0.001
T20.66 (0.62-0.69)< 0.0010.69 (0.65-0.74)< 0.001
T30.65 (0.63-0.68)< 0.0010.73 (0.70-0.76)< 0.001
T41 (reference)1 (reference)
AJCC N stage
Positive0.94 (0.91-0.97)< 0.001Dropped out of the model
Negative1 (reference)