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characteristics. Predictors of CSM were identified from previous studies
.
To assess the relationship between these characteristics and CSM,
uni- and multivariable Cox proportional hazards regression analyses
were performed. In addition, we used a forward stepwise selection
process to create our final model including all variables found to be
significant in the univariable analysis. Time to death from UCB was
calculated as the time from DR to death. Patients who did not die were
censored at the last time when their survival status was known, and
patients who died of other causes were censored at their time of death.
Due to the small number of deathsfrom other causes in our cohort, these
patients were censored at their time of death. Salvage chemotherapy and
regimen were modeled using time-dependent covariates. Patients who
received salvage chemotherapy were only included in the salvage
chemotherapy group fromthe time they received salvage chemotherapy
until their last known status. Before receiving salvage chemotherapy,
they were included in the nonsalvage group. An additional model for
time to DR was created using restricted cubic splines with knots at the
tertiles to account for nonlinearity as previously shown .
Our third aimwas to create a multivariable model and to compare its
discrimination to the previously published risk grouping. We used a
forward stepwise selection process. That is, the variable withthe highest
discrimination was used to start building our model. Variables that
improved the discrimination 0.005 were then added to the model.
Once variables that improved the discrimination by at least 0.005 were
exhausted, the selection process was stopped. Discrimination was
Table 1 – Patient characteristics of 967 patients with disease
recurrence after radical cystectomy for urothelial carcinoma of
the bladder
Clinical characteristics
Age, yr 66 (59–74)
Gender
Female 220 (23)
Male 747 (77)
Body mass index, kg/m2 (n = 805) 26 (23–28)
Smoker (n = 888)
Never 288 (30)
Past 360 (37)
Current 231 (24)
Unknown 88 (9)
Characteristics at radical cystectomy
Surgical approach
Open 952 (98)
Laparoscopic 5 (0.5)
Robotic 10 (1)
Pathologic T stage
pT0 4 (<1)
pTa 13 (1)
pTis 24 (3)
pT1 70 (7)
pT2 177 (18)
pT3 447 (46)
pT4 232 (24)
Pathologic N stage
pN0 574 (59)
pN+ 385 (40)
Unknown 8 (<1)
Lymphovascular invasion (n = 922)
Absent 421 (46)
Present 501 (54)
Concomitant carcinoma in situ (n = 932)
Absent 693 (74)
Present 239 (26)
Soft tissue surgical margin (n = 937)
Negative 793 (85)
Positive 144 (15)
Ureteral margin (n = 942)
Negative 892 (95)
Positive 48 (5)
Urethral margin (n = 942)
Negative 891 (95)
Positive 51 (5)
Biological characteristics at disease recurrence
ASA score (n = 216)
1 76 (35)
2 83 (38)
3 56 (26)
4 1 (<1)
Karnofsky performance status
10% 2 (<1)
20% 4 (<1)
30% 38 (4)
40% 27 (3)
50% 48 (5)
60% 108 (11)
70% 173 (18)
80% 253 (26)
90% 229 (24)
100% 85 (9)
Age-adjusted Charlson Comorbidity Index
0 60 (6)
1 152 (16)
2 193 (20)
3 197 (20)
4 159 (16)
Table 1 (Continued )
Biological characteristics at disease recurrence
5 110 (11)
6 53 (6)
7 24 (3)
8 10 (1)
9 4 (<1)
10 1 (<1)
11 1 (<1)
Unknown 3 (<1)
Alkaline phosphatase, U/l (n = 776) 101 (79–161)
Albumin, g/dl (n = 626) 3.8 (3.3–4.2)
GFR, ml/min (n = 834) 62 (46–82)
Hemoglobin, g/dl (n = 832) 12 (10.6–13.6)
Lactate dehydrogenase, U/l (n = 621) 225 (187–362)
Platelets, billion/l (n = 867) 272 (211–342)
White blood cells, billion/l (n = 869) 8.2 (6.4–10.6)
Treatment characteristics
Adjuvant chemotherapy 279 (29)
Adjuvant chemotherapy type
Noncisplatin 59 (21)
Cisplatin 188 (67)
Unknown 32 (12)
Salvage chemotherapy 363 (38)
Salvage chemotherapy type
Noncisplatin 110 (30)
Cisplatin 247 (68)
Unknown 6 (2)
Visceral metastasis 572 (59)
No. of visceral metastases
1 395 (41)
2 400 (41)
3 137 (14)
4 35 (3.6)
ASA = American Society of Anesthesiologists; GFR = glomerular filtration
rate.
All values are median (interquartile range) or number (%). Some variables
are missing data and marked with the actual number of patients.
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