Chemotherapy and Bladder Cancer. Blayne Welk UBC Urology Grand Rounds June 4, 2008

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Chemotherapy and Bladder Cancer Blayne Welk UBC Urology Grand Rounds June 4, 2008 Outline Review of Incidence and Impact of bladder cancer Neoadjuvant chemotherapy Adjuvant chemotherapy Bladder preservation protocols Conclusions 1

Epidemiology 6,600 cases in Canada (75% male) 1,750 deaths related to bladder cancer In Canada, the chance of: Developing bladder cancer: 3.5% Dying from bladder cancer: 1% Canada Cancer Statistics 2007 Epidemiology Percentage of new cancer cases by type (for males): 2

Epidemiology Incidence of bladder cancer is rising Bladder cancer mortality is decreasing Improved treatment Earlier diagnosis Change in tumor biology SEER database 1960-2005 Impact Bladder cancer almost always presents during a person s lifetime Autopsy studies rarely demonstrate incidental bladder cancer Implies all bladder cancers are of clinical significance and require treatment Campbells 9th Edition 3

Impact 70% bladder tumors are non-muscle invasive at presentation 20% 70% 10% Progression Probability of progression CIS >50% Ta Low Grade: 5-10% Ta High Grade: 15-40% T1 High Grade 30-50% Donat SM, 2003 4

Progression 2589 EORTC patients (1979-89) Significant variables Tumor (primary/recurrent) Number tumors Tumor size (</>3cm) Stage CIS Grade Sylvester, Eur Urol, 2006 Progression: Summary About 1/3 of bladder tumors are muscle invasive at presentation Risk factors will influence progression of lower stage lesions A significant number of bladder cancers will require radical treatment 5

Radical Cystectomy Standard of care for localized muscle invasive bladder cancer How well does our current gold standard perform? Radical Cystectomy Series of 300 patients operated on from 1990-1993 56% were T2/T3 22% received neoadjuvant chemotherapy 6% received neoadjuvant radiation JU 2001 6

Radical Cystectomy Ta/Tis: 6.7% -> 14.7% T1: 18.7% -> 6.3% T2/3: 61% -> 55.7% T4: 2.3% -> 12.7% Radical Cystectomy Overall survival Disease specific survival 7

Radical Cystectomy Worse outcomes for patients with nonorgan confined (T3/4) versus organ confined disease (T2a/b) N+ disease occurs in approximately 15% patients, and has higher disease specific/overall mortality (second only to stage in impact) 10% of patients had pt0 disease Questions Can chemotherapy improve survival of all patients? Neoadjuvant chemotherapy Can further therapy improve survival of patients with high risk disease (nonorgan confined, N+)? Adjuvant chemotherapy Is there a subset of patients with muscle invasive tumor that can be treated with bladder preservation protocols? 8

Neoadjuvant Chemotherapy Advantages Treat micrometastatic disease Predominant mechanism of distant recurrence Reduce the size of primary tumor, making local control easier Tolerance of chemotherapy is better preop Generally good performance status Good compliance with protocols Takes 6-8wks postop until ready for chemo Treat a small disease burden versus waiting for gross metastatic disease Can see if tumor is chemoresponsive based on cystoscopy, CT, physical exam Neoadjuvant Chemotherapy Disadvantages 1. Clinical staging only Correlated between clinical and pathological staging is poor 30% discrepancy in staging 9

Neoadjuvant Chemotherapy Disadvantages 2. Delay in definitive treatment 189 patients who had radical cystectomy for T2 TCC disease between 1987-2000 19 patients had delay >12wks (delay due to seeking multiple medical opinions) JU 2003 Neoadjuvant Chemotherapy 10

Neoadjuvant Chemotherapy Disadvantages 3. Systemic toxicity of chemotherapy EORTC/MRC trial 491 patients received neoadjuvant chemotherapy 80% patients received all 3 cycles of CMV 4.7% nephrotoxicity 1% mortality Neoadjuvant Chemotherapy Disadvantages SWOG trial 153 patients received neoadjuvant chemotherapy 87% patients tolerated at least 1 cycle of MVAC No deaths related to chemotherapy No difference in postoperative complications 11

Neoadjuvant Chemotherapy Disadvantages 4. Increased perioperative mortality after neoadjuvant chemotherapy Comparative study out of MD Anderson 140 patients randomized to: Cystectomy + 5 cycles MVAC 2 cycles MVAC cystectomy 3 cycles MVAC Millikan, J Clin Onc, 2001 Neoadjuvant Chemotherapy Immediate surgery 6 patients died from postop complications Immediate chemo 3 patients experienced fatal toxicity from MVAC 1 patient had rapid disease progression 12

Neoadjuvant Chemotherapy Potential disadvantages: Clinical stage only Delay to definitive surgery Systemic toxicity Once these factors are considered, is there actually a survival benefit? Neoadjuvant Chemotherapy Sternberg, Urol 2007 13

Neoadjuvant Chemotherapy 1989-1995 Multicentre trial Cisplatin, Methotrexate, Vinblastine Doxorubicin excluded due to RT interaction concerns and toxicity Lancet 1999 Neoadjuvant Chemotherapy Inclusion T2G3, T3, T4a patients TCC or TCC/squamous mixed tumors <7cm N0/NX patients GFR 50mL/min Randomised to receive 3 cycles of CMV (over 9wks) and cystectomy vs cystectomy alone Powered to detect 10% survival difference at 3 years 14

Neoadjuvant Chemotherapy Results 976 patients 491: chemo 392 of which received full course Mortality: 5 patients (1%) 465: no chemo 422 patients had cystectomy 18 deaths due to cystectomy (Mortality 3.7%) 415 patients had RT 66 had RT and cystectomy 80% of the deaths related to TCC Neoadjuvant Chemotherapy Results No significant difference in survival (p=0.06) 32.5% chemo patients had a complete response from neoadjuvant chemo/tur (p0), but didn t have significant increased survival 15

Neoadjuvant Chemotherapy Conclusions Trend toward improved survival (5%) Neoadjuvant CMV is safe Mortality 1% Well tolerated (80% completed 3 cycles of CMV) No evidence of increased progression due to delay to cystectomy Neoadjuvant Chemotherapy SWOG RCT 1987-1998 317 multicentre patients randomized to: M-VAC (3x 28d cycles) + cystectomy Cystectomy alone NEJM 2003 16

Neoadjuvant Chemotherapy Inclusion criteria T2-T4a N0M0 No prior RT ECOG 0-1 Stratified by Stage: T2 vs T3/4a Age <65 vs >65yrs Powered to detect a 50% improvement in median survival Neoadjuvant Chemotherapy Results Time to surgery: 17d vs 115d Chemo group: 1/3 had grade 4 granulocytopenia 1/3 had grade 3 toxicity (granulocytopenia, stomatitis, anemia, N/V etc) Postop complications: no difference between groups 17

Neoadjuvant Chemotherapy Median survival: 77 vs 46 mon (p=0.06) Survival advantage maintained across age and stage groups Neoadjuvant Chemotherapy Results M-VAC effect on tumor stage Number of tumors pt0 MVAC & cystectomy group: 38% Cystectomy only group: 15% (p<0.001) 5yr survival: 85% 18

Neoadjuvant Chemotherapy Conclusions Reduced risk of death: 25% Neoadjuvant M-VAC is safe No treatment mortality Grade 3/4 toxicity in 2/3 patients No evidence of increased perioperative complication, or inability to receive cystectomy Neoadjuvant Chemotherapy Nordic I (1985-89) 325 patients, T1G3-T4aNXM0 TCC Cisplatin and Doxorubicin (2cycles/6wks) Preop RT in all patients Nordic II (1991-97) 317 patients, T2-T4aNxM0 TCC Cisplatin and Methotrexate (3cycles/9wks) Eur Urol 2004 Nordic I: JU 1996 Nordic II: Scand J Urol Nephr 2002 19

Neoadjuvant Chemotherapy Neoadjuvant Chemotherapy Conclusions Trials similar in design, same centre specific protocols/followup used Small survival benefit from Nordic trials separately is more pronounced with combined analysis Neoadjuvant chemotherapy is safe Postop morbidity and mortality was similar between groups 20

Neoadjuvant Chemotherapy Summary Sternberg, Urol 2007 Neoadjuvant Chemotherapy 11 RCTs, 3005 patients Eur Urol 2005 21

Neoadjuvant Chemotherapy Neoadjuvant Chemotherapy Conclusions Best results from platinum based combination therapy Absolute survival benefit of 5% at 5yrs 22

Neoadjuvant Chemotherapy But Haven t reached the survival threshold of 10% (that clinicians felt would be significant to recommend therapy) No good QOL data to support neoadjuvant chemo Subgroup analysis: minimal benefit in of average risk pt2 patients Likely greater benefit in higher risk patients (pt3, N+), but hard to do RCT with these patient preselected Quality of surgery a confounder RCTs focus on best subgroup of bladder cancer patients Age primarily 60-75 (40% bladder cancer in SEER database >75yrs) ECOG 0-1 Cr clearance is <50mL/min in 50% those >70yrs Adjuvant Chemotherapy 50% patients with high grade Bladder Ca and T2b disease die within 2yrs of presentation Widely used for pt3-t4a or N+ disease Based on success with other solid organ tumors When used as primary therapy for N+/M+ disease, MVAC provides improved survival Risk factors: KPS <80%, visceral mets Survival: 33, 13, 9 mon with chemo 25-35% patients attain complete response 30-40% 5yr survival in chemo group, vs 17% for all patients 23

Adjuvant Chemotherapy Advantages Allows local control to be established first with radical cystectomy Treatment based on pathologic staging No delay in surgery Micrometastasis treated while volume still micro, rather than awaiting clinical mets 10-15% locally treated bladder cancer recurs within 6-12mon, suggesting micromets Adjuvant Chemotherapy Disadvantages Electrolytes and renal function may be worsened with ileal loop/neobladder Delay in therapy for occult metastasis No way to monitor tumor response to see if further cycles worth while MVAC chemo quite toxic Severe neutropenia, mucositis, N/V Renal/cardiac/neuro toxicities Toxic death rate 3% 24

Adjuvant Chemotherapy Randomized trials Sternberg, Urol 2007 Adjuvant Chemotherapy Skinner, USC, 1980-1988 91 patients Inclusion criteria Pathologic invasive bladder cancer T3, T4, or N+ (none above aortic bifurcation) and M0 Excluded Previous chemo/rt Poor end organ function KPS <50 Skinner, JU 1991 25

Adjuvant Chemotherapy Randomized to chemo or no chemo 6wks after radical cystectomy Chemo: 4 courses, q28d Cisplatin Doxorubicin Cyclophosphamide 17 initial patients treated with variety of cisplatin combinations Adjuvant Chemotherapy Results Median age 62 (22-75) 36% had N+ disease 67% T3, 24% T4 Chemo group 50% completed 3-4 cycles 34% completed 0-1 cycles Most stopped due to toxicity and uncertain benefit No deaths from chemo 26

Adjuvant Chemotherapy Survival Overall (n=91) 1 N+ (n=17) 2 N+ (n=16) Cystectomy Cystectomy & Chemo 2.4 yrs 4.25yrs P=0.10 1.4 yrs 7.6 yrs P=0.03 0.6 yrs 1.4 yrs P=0.23 Updated results 3yr survival 68% for cystectomy and chemo 3yr survival 47% cystectomy alone (p=0.06) Adjuvant Chemotherapy Criticisms of the study: Only 62% of eligible patients were entered Selection bias Underpowered: need 400-1000 patients for 10-15% survival difference Poor compliance with chemotherapy Variety of chemo protocols used initially Questionable statistical methods Subgroup analysis questionable Conclusions and significance from subgroups, not overall group 27

Adjuvant Chemotherapy Stockle, Mainz Germany, 1987-1991 pt3b, pt4a, or pn1/2 disease Randomized to receive 3 cycles MVAC/MVEC Goal: 100 patients Stockle, JU 1992 Stockle, JU 1995 Adjuvant Chemotherapy Results 49 patients randomized 60% N+ disease, most of which were T4 18/26 (69%) received 2-3 cycles of chemo Trial stopped after interm analysis 12/13 N+ control arm patients had progression 3/11 N+ chemo patients had progression 28

Adjuvant Chemotherapy PFS: 59% vs 13% P=0.0005 Adjuvant Chemotherapy Sternberg, Urol 2007 29

Adjuvant Chemotherapy 6 RCTs with 498 patients Cystectomy for local control All used cisplatin based chemotherapy (most in combination) Eur Urol 2005 Adjuvant Chemotherapy 30

Adjuvant Chemotherapy Adjuvant Chemotherapy Conclusion 9% improved survival at 3yrs with cisplatin based chemo Used individual patient data, therefore could look at overall survival, and standardize stats But Would need 900 patients to detect 9% survival benefit Poor statistical design Small sample size Trails often stopped early (4/6) Modest evidence at best 31

Adjuvant Chemotherapy Is there hope for better evidence EORTC-30994 660 patients (started 2001) Randomised to immediate vs deferred chemo TCC, pt3/4 or N+ disease Start chemo within 90 days of cystectomy 4 cycles of Classical MVAC High dose MVAC GC Adjuvant Chemotherapy Endpoints: Overall survival Progression free survival 32

Multimodal bladder preservation If we want to challenge the gold standard we need to know: What is the survival of the gold standard? What is the quality of life of the gold standard? Multimodal bladder preservation What is the mortality associated with a cystectomy, and what is the 5yr survival? 66% 35% 27% Sternberg, Urol 2007 33

Multimodal bladder preservation What is the QOL after a cystectomy? Orthotopic bladders have higher QOL than Ileal conduit Leakage easier to disguise Better cosmetics Normal voiding Close to QOL with intact bladder QOL dependent on preop expectations Hautmann, JU 2003 Multimodal bladder preservation Can these results be matched in select patients with a multimodal bladder preservation approach? 10-15% patients are p0 after radical cystectomy Neoadjuvant chemo results in increased p0 cancers SWOG trial: p0 38% neoadj chemo vs 15% cystectomy alone EORTC trial: p0 33% neoadj chemo 34

Multimodal bladder preservation What happens with patients treated with TURBT alone for T2 disease? Sternberg, Urol 2007 Multimodal bladder preservation 151 patients (1979-1989) treated by cystectomy or TUR alone Underwent initial TUR by other urologist, then restaging TUR of tumor/scar down to fat and 1-2cm of normal mucosa by Herr If repeat TUR had T0, Tis, or T1 they were given choice: radical cystectomy or bladder preservation Recommended salvage cystectomy if Recurrent T1/T2 disease BCG refractory CIS CT abnormalities Herr JCO 2001 35

Multimodal bladder preservation Multimodal bladder preservation 36

Multimodal bladder preservation Who may be a candidate for this approach? Stage T2 Tumor <3cm Absence of hydronephrosis Absence of palpable mass Unifocal disease Multimodal bladder preservation What can be gained with the addition of chemotherapy? Sternberg, Urol 2007 37

Multimodal bladder preservation Sternberg: 104 T2-T4N0 patients treated with MVAC & restaged 52 responded & received TUR 13 responded & received Partial Cystectomy 39 Radical cystectomy Those with TUR: 50% pt0 60% 5yr survival (45% with bladder) Whether you responded to chemo determined survival Responders (pt0): 69% 5yr survival Nonresponders (T2): 27% 5yr survival Conclusions Neoadjuvant chemotherapy Disadvantages: Clinical stage only (30% discordance) Delay to definitive surgery Systemic toxicity Associated toxicity and mortality (1-3%) acceptable with MVAC, likely better with GC Best available data suggests a modest increased survival (5% at 5yrs) Benefit minimal for T2, likely increased for T3/4 or N+ disease 38

Conclusions Adjuvant chemotherapy Advantages Rapid local control Treatment based on p stage Micrometastasis treated Disadvantages Electrolytes and renal function may be impaired Delay in therapy for occult metastasis No way to monitor tumor response Chemotherapy toxicity Quality of evidence is lacking, and upcoming, well powered multicentre RCTs (EORTC 30094) should be used for future patient therapy Conclusions Bladder preservation Should be approached cautiously No RCTs comparing TUR/Chemo/RT to cystectomy Patients must be motivated, willing to accept intensive followup, and the risk of delayed cystectomy Patients that are candidates: T2 disease Tumor <3cm No hydro, no palpable mass Unifocal disease No CIS After first TUR, should reresect at 3mon. Residual disease should prompt consideration of cystectomy Addition of chemotherapy has produced survival similar to radical cystectomy in small series Failure to respond to chemotherapy should prompt urgent cystectomy Morbidity of chemotherapy +/- RT may be significant 39

Thank you Multimodal bladder preservation What an be gained with the addition of RT? Sternberg, Urol 2007 40

Multimodal bladder preservation Phase I/II RCT from RTOG 95-06 1995-1997 34 patients T2-4a, Nx, M0 No hydro Kaufmann, Onc 2000 Multimodal bladder preservation 41