Table 3. Published papers and abstracts documenting pCR in preoperative chemoradiation studies using cetuximab.
| No of pts* | Cetuximab | Capecit | 5-FU | Oxaliplat | Irinotecan | RT dose | PCR** | R0*** | Good TRG*** | |
|---|---|---|---|---|---|---|---|---|---|---|
| Chung 2006 (45) | 20 | Yes | Yes | No | No | 50.4 Gy/28#/38 | 2/17 (12%) | 17/17 (100%) | NS | |
| Machiels 2007 (46) | 40 | Yes | Yes | No | No | 45 Gy/25#/33 | 2/40 (5%) | >2 mm, 27/40 (73%) | Few cells only, 10/40 (25%) | |
| Rodel 2007 (47) | 48 | Yes | Yes | Yes | No | 50.4 Gy/28#/38 | 4/48 (8%) | 42/45 (93%) | Good (>50%), 10/45 (21%) | |
| Hofheinz 2006 (48) | 20 | Yes | Yes | No | Yes | 50.4 Gy/28#/38 | 5/20 (25%) | 18/20 (90%) | 6/20 30%) | |
| Horisberger 2009 (49) | 50 | Yes | Yes | No | Yes | 50.4 Gy/28#/38 | 4/50 (8%) | 50/50 (100%) | 30/50 (60%) | |
| Bertolini 2007 (50) | 40 | Yes | Yes | No | No | 50 Gy/25#/33-50.4 Gy/28#/38 | 3/40 (7.5%) | 36/38 (95%) | Dworak 8/38 (21%) | |
| Hong 2007 (51) | 10 | Yes | Yes | No | Yes | 50.4 Gy/28#/38 | 2/10 (20%) | 10/10 (100%) | 2/10 (20%) | |
| Cabebe 2008 (52) | 23 | Yes | Yes | No | First 10 pts only | No | 50.4 Gy/28#/38 | 4/23 (17%) | NS | NS |
| Eisterer 2009 (53) | 28 | Yes | Yes | No | No | 45 Gy/25#/33 | 0/28 (0%) | NS | NS | |
| Velenik 2010 (54) | 37 | Yes | Yes | No | No | No | 45 Gy/25#/33 | 3/37 (8.1%) | NS | TRG3 7/37 (18.9%) |
| Kim 2011 (55) | 40 | Yes | Yes | No | No | Yes | 50.4 Gy/28#/38 | 9/39 (23%) | TRG3 3/39 (7.7%) | |
| Dewdney 2012 (56) | 83 | Yes | Yes | No | Yes | No | 50.4 Gy/28#/38 | 15/83 (18%) | 74/83 (89%) | NS |
| Dewdney 2012 KRAS/BRAF wild-type tumors (56) | 46 | Yes | Yes | No | Yes | No | 50.4 Gy/28#/38 | 5/46 (11%) | 43/46 (93%) | NS |
| Sun 2012 (57) | 63 | yes | Yes | No | No | No | 50.4 Gy/28#/38 | 8/63 (12/7%) | ||
| Total | 502 | Yes –all | 45-50.4 Gy | 61/502 (12%) |
*number entering study; **number having had surgery; ***using tumour regression grading not yp (various systems used); NS, not specified; RT, radiotherapy; PCR, pathological complete response; R0 resection, curative resection; TRG, tumour regression grade; (NB The terms Tmic and TRGs remain unvalidated surrogate endpoints, and the lack of consistency in their reporting, hinders their interpretation as a measure of response within rectal cancer trials). TheExpert-C trial was originally designed to detect a 20% improvement in pCR, but in the light of Kras/Braf wildtype/mutant efficacy data was amended to analyze the primary end point of complete response in patients with KRAS/BRAF wild-type tumors only