Neoadjuvant therapy of rectal cancer – how can we make it better? Claus Rödel Department of Radiotherapy University of Frankfurt, Germany Honoraria: Roche, Sanofi-Aventis Research Funding: Merck Roche

O U T L I N E How can we make it more efficient (or less toxic)? - RT with 5-FU - RT with 5-FU/Cape plus oxaliplatin - RT with targeted agents - induction chemotherapy - without RT?, radical surgery? How can we select better? - molecular? - clinical?

FFCD 9203 R OP RT: 45 Gy Gérard JP et al, J Clin Oncol 2006 5-FU: 350 mg/m²/d LV: 20 mg/m²/d RT: 45 Gy OP Gérard JP et al, J Clin Oncol 2006

FFCD 9203 – Local Failure RT: 16.5% RCT: 8.1% p < 0.05 Gérard JP et al, J Clin Oncol 2006 Similar Results: EORTC 22921: Bosset et al., N Engl J Med 2006

ASCO 2010: Ngan et al, abstract # 3509 5 x 5 Gy versus 5-FU CRT ? p=0.8 p=0.17 9.0% 14.2% P O L I S H Bujko et al., Br J Surg 2006 AUSTRAL I A T3NxM0 5 x 5 Gy 5-FU CRT P Number of pts. 163 3-year LR rates 7.5% 4.4% 0.24 5-year M1 28% 31% 0.85 5-year OS 74% 70% 0.56 ASCO 2010: Ngan et al, abstract # 3509

Phase I/II Studies of RT with new agents 50.4 Gy Radiotherapy: 28 x 1.8 Chemotherapy: Oxaliplatin 50 mg/m²/d Weeks 1 2 3 4 5 6 d 1 - 14 d 22 - 35 Capecitabine 1650 mg/m²/d d1 d 8 d 22 d 29 Rödel et al., J Clin Oncol 2003 and J Clin Oncol 2007

Tumor-Regression-Grading CAPOX-RT 5-FU-RT (n=110) (n=385) Complete Regression (100%) 16% 10% Good Regression (> 50%) 59% 52% Moderate Regression (25-50%) 11% 14% Poor Regression (< 25) 10% 15% No Regression (0%) 3% 8%

ACCORD 12/0405-Prodige 2 R OP OP Cape: 800 mg/m²/bid Adjuvant Chemotherapy (local policy) R 45 Gy/1.8 Gy SD OP Oxaliplatin: 50 mg/m²/week Cape: 800 mg/m²/bid 50 Gy/2.0 Gy SD Adjuvant Chemotherapy (local policy) Gérard JP et al, J Clin Oncol 2010;28-1638-44

ypCR (primary endpoint) 13.9% 19.2% 0.09 ACCORD 12 Preop. Cap 45 Preop Capox 50 P Number of pts. 299 ypCR (primary endpoint) 13.9% 19.2% 0.09 ypCR+”few residual cells” 28.9% 39.4% 0.008 CRM: 0-2 mm 19.3% 9.9% 0.02 Acute Tox ≥ 3 11% 25% <0.001 Similar results: STAR-Trial, Aschele C et al, J Clin Oncol 2009 (abstr. CRA4008)

CAO/ARO/AIO-04 R 5-FU RT 50.4 Gy + 5-FU 4#, q29 RT 50.4 Gy + mFOLFOX (best arm CAO/ARO/AIO-94) RT 50.4 Gy + 5-FU/Oxaliplatin T M E 5-FU 4#, q29 mFOLFOX 8#, q15 R Similar Design: PETACC 6: CAP+/-OX-RT – TME – CAP+/-OX NSABP R-04: CAP-RT+/-OX vs. 5-FU-RT+/-OX

Compliance to (neo-) adjuvant CAPOX cycle 1 cycle 2 100 % 100 % 95 % 96 % cycle 3 cycle 4 T M E cycle 5 cycle 6 70 % C a p O x 65 % 62 % 62 % 57 % 57% 53 % 52 % RT 50.4Gy Rödel C. et al. J Clin Oncol 2007;25:110-117

Grupo Cáncer de Recto 3 Study R MRT- defined Poor Risk: ≤ 2mm to mesorectal fascia, low-lying T3, T3N+, T4 RT 50.4 Gy + Cape/Oxaliplatin CAPOX 4#, q21 T M E R RT 50.4 Gy + Cape/Oxaliplatin CAPOX 4#, q21 T M E Fernández-Martos C, J Clin Oncol, 2010;28:859-65

CRT+TME+ adjuvant CAPOX Induction-CAPOX + CRT + TME N=56 P R0 resection rates 87% 86% n.s. pCR 13% 14% Compliance 4 X CAPOX 54% 91% <0.001 Toxicity (Grad 3/4) CAPOX-RT CAPOX 29% 23% 19% 0.36 0.004 Fernández-Martos C, J Clin Oncol, 2010;28:859-65 ASCO 2010: Similar trial: Maréchal et al, abstract # 3637

Rödel C et al., Int J Radiat Oncol Biol Phys 2008 Phase I/II Preoperative Radiotherapy with CAPOX and Cetuximab for Rectal Cancer Radiotherapy: 50.4 Gy 28 x 1.8 Gy Chemotherapy d 1 - 14 d 22 - 35 Capecitabine (1650 mg/m²/d) Oxaliplatin (35-50 mg/m²/d) d 1 d 8 d 22 d 29 6 x 250 mg/m²/d Cetuximab d -7 d 1 d 8 d 15 d 22 d 29 d 35 1 x 400 mg/m² Week -1 1 2 3 4 5 6 Rödel C et al., Int J Radiat Oncol Biol Phys 2008

Tumor-Regression-Grading CAPOX-RT+CET (n=45) Complete Regression (100%) 9% Good Regression (> 50%) 38% Moderate Regression (25-50%) 27% Minimal Regression (< 25) 22% No Regression (0%) 4% CAPOX-RT (n=110) 16% 59% 11% 10% 3% Confirmed by a randomized phase II trial: McCollum et al., abstract #3635

Phase I/II Präop. Bevacizumab/5-FU/RT Day 1 8 15 29 43 52 50.4 Gy 5-FU-Inf BEV 5-10 mg/kg Willett CG et al., Nat Med 2004 Willett CG et al., J Clin Oncol 2009

Phase I/II Preop. Bevacizumab/5-FU/RT Before treatment 12d post Bevacizumab Willett CG et al., Nat Med 2004 ypT0: 5/32 (16%), ypN0:59% No grad 4/5 tox; postop. complications: 13/32 (41%) 5-y local control: 100% 5y distant control: 75% Willett CG et al., J Clin Oncol 2009

ASCO 2010: Ongoing trial: Fernandes-Martos et al., abstract #TPS169 MSKCC-Pilot trial without RT Stage II/III, excluding T4 + low tumors needing APR 4 x Bev-FOLFOX 2 x FOLFOX (5-FU Chemo-RT only if SD/PD) OP Results: 8/29 (27%) with pCR (all no CRT) Schrag D et al., ASCO 2010, abstract 3511 ASCO 2010: Ongoing trial: Fernandes-Martos et al., abstract #TPS169

Garcia-Aguilar, J. et al., ASCO 2010, abstract #3510 ACOSOG Z6041: Local Excision uT2uN0 rectal cancer Oxaliplatin: 50 mg/m²/weeks 1,2,4,5 Cape: 725 mg/m² 5 days/week 50.4 Gy/1.8 Gy SD Results: RO 98%; pCR 36/81 (44%), 6% ypT3 Garcia-Aguilar, J. et al., ASCO 2010, abstract #3510

O U T L I N E How can we make it more efficient (or less toxic)? - RT with 5-FU - RT with 5-FU/Cape plus oxaliplatin - RT with targeted agents - induction chemotherapy - without RT?, radical surgery? How can we select better? - molecular? - clinical?

Biomarkers for Response to Chemoradiation Ghadimi et al., J Clin Oncol 2005 n=30, 50.4 Gy/5-FU 54 differentially expressed genes for the endpoint TRG/Downstaging Rimkus et al., Clin Gastroenterol Hepat 2008 N=42, 45 Gy/5-FU 43 differentially expressed genes for the endpoint TRG No concordance with even one gene between the 2 studies!!

Clinicopathological Selection Easy in former times: …postoperative chemoradio- therapy: rectal cancer < 12 cm from anal verge pT3-4 or pN+ …preoperative RT (5x5 Gy): any rectal cancer < 15 cm

Five US postoperative phase III studies, n=3791 Pooled Analysis : Five US postoperative phase III studies, n=3791 Low Risk pT1-2/N0 Intermediate Risk pT3/N0 and pT1-2/N1 Moderately high Risk pT1-2/N2 and pT3/N1 and pT4/N0 High Risk pT3/N2 and pT4/N1-2 Not included „May not require RT“ Gunderson et al., J Clin Oncol 2004

Circumferential Resection Margin MERCURY Study Group BMJ 2006 Radiology 2007 Nagtegaal ID, Quirke P. , J Clin Oncol 2008

TN- and CRM-defined Risk Stratification Multidisciplinary team discussion n=197 rectal cancer patients Surgery only: T1/2, T3a, N0/1, CRM- 116 (59%) Preop. CT+CRT: >T3a, N2, CRM-; CRM +, low T3 81 (41%) Histological CRM – 97% Histological CRM - 100% 75% Does pCRM- imply that these patients do not benefit from preop. RT? Burton et al. Br J Cancer 2006

Preoperative Radiotherapy vs. Risk-adapted postoperative CRT: MRC CR07 5x5Gy+TME TME alone (Postop CRT only if CRM+) 5y-Local recurrence: CRM + 13.8% 20.7% HR 0.64 (0.25-1.64) CRM - 3.3% 8.9% HR 0.36 (0.23-0.57) Sebag-Montefiore D et al., Lancet 2009:373:811-20

S U M M A R Y Neoadjuvant CRT with 5-FU - Inclusion of oxaliplatin CRT: ACCORD, STAR not convincing NSAPB R-04 completed CRT+adj. CT: CAO/ARO/AIO-04 completed PETACC 6 open Ind.-CT+CRT: Grupo Cáncer de Recto 3 Study - Inclusion of targeted agents: phase I/II - without RT: subgroups (not T4, low) - with local excision: subgroups (uT2N0) Selection - molecular: investigational - clinical: MRI-defined (CRM-)?