Abstract
Introduction
Time that passes between an unfavourable diagnosis to a radical cystectomy (RC) affects oncological outcomes in patients with bladder cancer. Unsatisfactory survival of patients after RC in Central Europe can potentially result from this factor.
Material and methods
The aim of this study was to assess the time interval between transurethral resection of the bladder tumor (TURBT) and RC in Central Europe and to identify clinical factors of possible delays. 941 consecutive patients who underwent RC in nine Central European urological centers were enrolled into the study. After the TURBT–RC time was calculated, selected clinical and pathological parameters were tested as potential factors influencing the timing of RC.
Results
On average, RCs were performed 73.8 days after TURBTs (median – 53, range 0–1587). In 238 patients (25.3%) the time exceeded 12 weeks. Patients with muscle–invasive cancer were operated earlier on than patients with nonmuscle–invasive cancer (67.6 vs.105.2 days, RR = 1.41, p = 0.00). In high volume centers (>30 RC per year) longer TURBT–RC intervals were observed (97.6 vs. 66.3 days, RR = 2.49, p = 0.00). Simultaneously, factors such as female sex (RR = 1.21), more advanced age of patient (>65 years, RR = 1.23), presence of concomitant CIS (RR = 2.43), grade of cancer cells (RR = 1.67) and final post–RC stage (RR = 1.51) had no statistically significant effect on the results (p >0.05).
Conclusions
The mean time interval between the diagnosis and radical treatment of patients with bladder cancer in Central Europe is adequate. However, there are still a relatively high number of patients waiting for radical cystectomy longer than 8 weeks. A lower stage of disease as well as a higher case load within of a hospital may delay the surgery.
Keywords: bladder cancer, cystectomy, time to treatment, preoperative care, clinical practice pattern
INTRODUCTION
Radical cystectomy (RC) remains the treatment of choice in patients with muscle–invasive bladder cancer (MIBC), as well as with nonmuscle–invasive bladder cancer (NMIBC), which has the highest risk of progression [1, 2]. Despite improvements in diagnosis and surgical techniques, the oncological results of the surgery are far from being satisfactory. Currently reported 5–year overall survival in large series of patients is as low as 29–63% [3–5]. In Central Europe these numbers may be even be lower [6, 7]. There are many factors potentially influencing outcomes of RC, including patient–, cancer– and urologist–related factors. The time from undertaking the decision about RC to surgery is one of the most prominent. While the general rule is “the shorter the time, the better the results”, it is proven that exceeding the 12–week or 3–month time period is associated with more advanced cancer stages and reduced survival [8–13]. Until now the data on the timing of RC has been limited, while in Central Europe only Polish data has been recently published [14].
The aim of this study was to assess the time that patients with bladder cancer wait from TURBT to RC in Central European countries and to determine the underlying factors for possible delays.
MATERIAL AND METHODS
Retrospective analysis, covering 941 consecutive patients who underwent RC between 2007 and 2013 in nine Central European hospitals from 4 countries was performed. The single inclusion criterion was RC performed due to bladder cancer within the analysed study period. Exclusion criteria were not established. Table 1 presents the detailed characteristics of this study population.
Table 1.
Number of patients | 941 |
Number and percentage of men | 729 (77.5%) |
Number and percentage of women | 212 (22.5%) |
Mean age of patients and standard deviation | 65.2 ±8.6 years |
Range | 29–89 years |
Number and percentage of patients according to stage of bladder cancer diagnosed after TURBT | |
Stage Ta | 10 (1.1%) |
Stage T1 | 139 (14.8%) |
Stage T2–T4 | 762 (81.0%) |
Carcinoma in situ | 7 (0.7%) |
Stage not available | 23 (2.4%) |
Number and percentage of patients according to stage of bladder cancer diagnosed after RC | |
Stage T0 | 34 (3.6%) |
Stage Ta | 10 (1.1%) |
Stage T1 | 81 (8.6%) |
Stage T2 | 244 (25.9%) |
Stage T3 | 318 (33.8%) |
Stage T4 | 233 (24.8%) |
Carcinoma in situ | 14 (1.5%) |
Stage not available | 7 (0.7%) |
RC – radical cystectomy; TURBT – transurethral resection of bladder tumor
Primary study endpoint was the time from TURBT to RC. In patients with a history of multiple TURBT, the date of the last resection was analysed. Additionally, an attempt to identify clinical factors influencing primary endpoint was taken. These factors included patient age and sex, cancer grade and stage diagnosed histologically in the TURBT specimen, final cancer stage diagnosed histologically in the RC specimen, as well as the case load of the hospital.
All statistical calculations were performed using Statistica 10.0 Software. Shapiro–Wilk test confirmed the normal distribution of all variables. Levene test was applied for the assessment of the equality of variances. If the result was <0.05, F–Welch test was used for comparison of the differences between subgroups. Otherwise, results were compared with an unpaired t–test.
RESULTS
The mean time from TURBT to RC was 73.8 days and the 12–week (84 days) interval was exceeded in 238 patients (25.3%). Table 2 summarizes the results and presents data obtained in each study center. Table 3 presents the influence of basic clinical and pathological features on the primary study endpoint. Time to RC occurred to be dependent with statistical significance on muscle invasiveness of the cancer diagnosed in the TURBT specimen and the case load of the hospital. Patients with NMIBC were operated on average 38 days later than patients with MIBC. This led to a 10% increase in the absolute risk and 1.4 fold higher relative risk of exceeding the 84–day time frame in the group of NMIBC patients. Interestingly, in high volume centers defined as hospitals, there were over 30 cystectomies performed annually, with the mean time from TURBT to RC being longer by 31 days. The absolute risk increase and the relative risk of performing RC beyond the 84–day time frame in patients operated in high volume centres was 28% and 2.5, respectively. Finally, the impact of patient age, patient sex, presence of concomitant CIS foci, cancer grade, as well as final cancer stage was found to be statistically insignificant in relation to the time from TURBT to RC.
Table 2.
Study center | Character of study center | Number of RC performed within analysed period | Percentage of patients qualified for RC due to NMIBC | TURBT–RC time in days | Percentage of patients in whom TURBT–RC time exceeded 84 days | ||
---|---|---|---|---|---|---|---|
Mean value | Standard deviation | Range | |||||
TOTAL | Academic and regional hospitals | 941 | 17 | 73.8 | 92.8 | 0–1587 | 25.3 |
A | Academic hospital | 101 | 26.0 | 62.2 | 65.8 | 7–570 | 17.2 |
B | Regional hospital | 28 | 10.7 | 71.2 | 103.8 | 12–562 | 17.9 |
C | Academic hospital | 227 | 13.7 | 97.2 | 74.3 | 8–617 | 46.1 |
D | Academic hospital | 175 | 17.6 | 76.4 | 95.6 | 0–1217 | 33.9 |
E | Regional hospital | 58 | 10.3 | 52.5 | 22.3 | 4–90 | 10.3 |
F | Regional hospital | 107 | 18.4 | 70.1 | 66.9 | 4–575 | 23.2 |
G | Academic hospital | 29 | 41.4 | 93.3 | 284.6 | 3–1587 | 10.3 |
H | Academic hospital | 137 | 0.0 | 44.5 | 6.1 | 33–68 | 0.0 |
I | Regional hospital | 101 | 34.7 | 78.0 | 120.8 | 3–720 | 22.8 |
NMIBC – non muscle–invasive bladder cancer; RC – radical cystectomy; TURBT – transurethral resection of bladder tumor
Table 3.
Variable | Definition | Number of cases | ARI >84 days | RR >84 days | Time (mean value) | P value |
---|---|---|---|---|---|---|
Patient age | >64 yrs vs. <65 yrs | 501 vs. 439 | 5.2% | 1.23 | 79.1 vs. 67.9 days | 0.06 |
Patient sex | Female vs. male | 212 vs. 729 | 5.1% | 1.21 | 75.0 vs. 73.5 days | 0.83 |
Initial cancer stage (TURBT) | NMIBC vs. MIBC | 156 vs. 762 | 9.7% | 1.41 | 105.2 vs. 67.6 days | 0.00 |
Concomitant Cis | Present vs. absent | 7 vs. 911 | 33.5% | 2.43 | 90.4 vs. 73.9 days | 0.64 |
Grade of cancer cells | HG tumors vs. LG tumors | 582 vs. 343 | 11.9% | 1.67 | 75.7 vs. 71.7 days | 0.53 |
Final MIBC stage (RC) | T3&T4 tumors vs. T2 tumors | 551 vs. 244 | 8.6% | 1.51 | 73.2 vs. 63.6 days | 0.15 |
Case load | >15 op/yr vs. <15 op/yr | 690 vs. 251 | 9.4% | 1.51 | 75.2 vs. 70.0 days | 0.45 |
>30 op/yr vs. <30 op/yr | 226 vs. 715 | 27.6% | 2.49 | 97.6 vs. 66.3 days | 0.00 |
ARI > 84 days – absolute risk increase of RC performed >84 days from diagnosis; Cis – carcinoma in situ, HG – high–grade; LG – low–grade; MIBC – muscle–invasive bladder cancer; NMIBC – non muscle–invasive bladder cancer, op/yr – mean number of RC performed in a centre per year; RC – radical cystectomy, RR > 84 days – relative risk of RC performed >84 days from diagnosis; TURBT – transurethral resection of bladder tumor; yrs – years.
The age of patients operated within 8 weeks from TURBT was lower by 1.12 years in comparison to patients operated after 8 weeks (64.7 vs. 65.8 years, p = 0.05). No residual tumor at RC was found in 34 cases (3.6%). Among patients who qualified for RC due to NMIBC, MIBC were finally diagnosed in 96 cases (61.5%).
DISCUSSION
Time from establishing indications for RC to surgery correlates with the chance of diagnosis of an organ confined disease and affects recurrence–free, as well as overall survival [8–13]. Many studies addressed this issue in the past, as presented in Table 4. Only one study did not reveal the relationship between the timing of RC and its outcomes [15]. With relatively consistent conclusions from these papers, experts of the European Association of Urology advise to not delay RC by more than 3 months [1].
Table 4.
Author, year | Number of patients* | Mean time from initial diagnosis to RC | Established maximal time interval | Percentage of patients operated within maximal time interval | Mean follow–up | Consequences of exceeding maximal time interval |
---|---|---|---|---|---|---|
Gore et al. 2009 [8] | 441 | n.a. | 12 weeks | n.a. | n.a. | Increased risk of disease–specific mortality in 2–year follow–up – HR 7.7 |
Lee et al. 2006 [9] | 214 | 61 days | 93 days | 87.9% | 40 months | Higher overall mortality – 54% vs. 39% Higher disease–specific mortality – 35% vs. 25% No effect on the risk of non–organ confined disease |
May et al. 2004 [10] | 189 | 1.8 months | 3 months | 77.8% | 40 months | Higher rate of T4 disease – 31 vs. 14% Decreased 5–year overall survival – 26% vs. 54% Decreased 5–year progression–free survival – 34% vs. 55% |
Chang et al. 2003 [11] | 153 | 63 days | 90 days | 87.6% | – | Higher rate of stage T3 or higher – 81% vs. 52% |
Sanchez–Ortis et al. 2003 [12] | 189 | 7.9 weeks | 12 weeks | 89.9% | 36 months | Higher rate of extravesical (T3 or T4 and/or N + ) disease – 84% vs. 42.8% Decreased 3–year overall survival – 34.9% vs. 62.1% |
Hara et al. 2002 [13] | 50 | 2.65 months | 3 months | 56% | 50.8 months | Reduced 5–year recurrence–free survival – 52.5% vs. 86.9% Reduced 5–year overall survival – 47.3% vs. 80.3% Increased risk of vascular involvement – 73% vs. 46% No effect on the risk of non–organ confined disease |
Papers cited in table covers only MIBC cases
We performed a retrospective analysis of the time from clinical qualification to RC in selected and representative urological centers of Central Europe. The study was conducted in both academic and non–academic hospitals to bring reliable data, that could be extrapolated to the region of Central Europe. The main finding was that mean and median time intervals remained within a frame of 3 months. However, one fourth of the patients waited for RC more than 12 weeks (84 days). Even if we would start counting days not from TURBT, but from pathological diagnosis, there would still be a 20% – portion of patients in whom RC was delayed. While we adopted the time from TURBT to RC as the most unequivocal, authors of papers cited in Table 4 adopted time from initial diagnosis to RC. This can be defined as time from a pathological report, from additional imaging or from some additional clinical tests.
The strongest predictor for delayed RC in a recent study was qualification to surgery due to NMIBC. The subgroup of NMIBC patients that qualified for RC required special attention. Schrier et al. first showed that patients initially diagnosed as MIBC have more favourable prognosis compared to patients with progressive NMIBC [16]. The subgroup of patients with NMIBC who require RC is not always easy to identify. In addition, these patients are more likely to refuse RC compared to MIBC patients. However, in these cases RC should not be delayed, since with increasing time to RC, the survival decreases significantly [17–20]. What is more, the risk of being upstaged to MIBC increases with time to RC [18]. Interestingly, as much as 61.5% of NMIBC patients from a recent analysis were finally staged as MIBC. Hautmann et al. found also that the rate of non–organ confined disease and nodal metastasis is higher in patients qualified for RC after initial diagnosis than after recurrence [18]. However, nodal status was not analysed in our study.
Another statistically significant factor for the delay of RC in our study was the high case load of the hospital. This was probably the effect of the transfer time from other hospitals. Liedberg et al. observed significantly longer time to RC among patients who were referred to surgery from other hospitals. In the group of 141 patients they noticed the difference of 22 days (63 vs. 41 days) [15]. However, having an increased risk of delayed RC, patients operated on in high volume centers have lower surgical morbidity and mortality [21–24]. We should be very careful then when formulating final conclusions.
Within this analysis the impact of patient age on the time from TURBT to RC was also analysed. In older patients RC was associated with increased morbidity, which could potentially hamper the decision about surgery in both the urologist and patient [25]. In the recent study, clinically significant difference in time to RC was observed between representative groups of patients aged below and above 65 years. However, this difference remains statistically insignificant with a borderline p–value of 0.06. Also patient sex, presence of concomitant CIS foci, cancer grade and final cancer stage had no statistically significant effect on time from TURBT to RC.
Within this study, not all reasons for the possible delay of RC were analysed. Therefore, their identification is of utmost importance. From literature review the most common were patient–related, including the search for second medical opinion and the preference of surgery date. They covered 50–84% of cases [9, 10, 12]. Others included comorbidities and temporary medical contraindications, need for a transfer to the reference center, fear of surgery and related morbidity, as well as unsuccessful attempts of bladder–sparing treatment. In a historical cohort presented by Hautmann et al., the option of an ileal neobladder shortened the time to RC by almost one year. As a consequence, the survival rates were much higher in the neobladder group compared to the ileal conduit group [26]. We can suspect that the implementation of tissue engineering to reconstruction of the lower urinary tract will further improve this data; however, this technology is still challenging [27]. Recent analysis also did not include data on additional imaging, necessary before RC. While this issue was not addressed in previously published papers, authors cannot exclude that selection and extent of the imaging, as well as its availability also influence the time to RC. Finally Gore et al. noticed a longer time to RC among nonwhites and unmarried individuals. However, the differences were not statistically significant [8].
The Polish data on timing of RC was recently published [14]. The comparison of Central European data with Polish data seemed to be interesting. Both studies outlined the impact of the profile of the hospital on the time from TURBT to RC. In the Polish study, regional, but not university hospitals noticed the shortest time to RC. In our study, the longest time to RC was observed in high volume centers. However, the comparison of Polish and Central European results were significantly limited by at least two factors. First, Central European analysis covered data from 3 centers included into Polish analysis. Second, Polish analysis covered significantly less patients, which influenced statistical calculations.
The most important limitation of this study was the retrospective nature and hence the inclusion criterion of performed RC instead of qualification for RC. This probably reduced the number of patients requiring RC by ignoring patients who died before RC was performed, as well as patients who refused to be operated on.
CONCLUSIONS
The mean time interval between the diagnosis and radical treatment of bladder cancer patients in Central Europe is adequate. However, a significant percentage of patients wait for radical cystectomy longer than 12 weeks. Special attention must be paid to patients with high risk NMIBC, as well as those who need transfer to a reference hospital, since lower stage of the disease and higher case load of a hospital may delay the surgery.
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