Epidermal growth factor receptor gene copy number, K-ras mutation and pathological response to preoperative cetuximab, 5-FU and radiation therapy in locally advanced rectal cancer.
Ann Oncol
; 20(3): 469-74, 2009 Mar.
Article
en En
| MEDLINE
| ID: mdl-19095777
ABSTRACT
BACKGROUND:
Cetuximab improves activity of chemotherapy in metastatic colorectal cancer (mCRC). Gene copy number (GCN) of epidermal growth factor receptor (EGFR) has been suggested to be a predictive factor of response to cetuximab in patients (pts) with mCRC; on the contrary, K-ras mutation has been associated with cetuximab resistance. PATIENTS ANDMETHODS:
We have conducted a phase II study with cetuximab administered weekly for 3 weeks as single agent and then with 5-fluorouracil and radiation therapy as neo-adjuvant treatment for locally advanced rectal cancer (LARC). EGFR immunohistochemistry expression, EGFR GCN and K-ras mutation were evaluated on diagnostic tumor biopsy. Dworak's tumor regression grade (TRG) was evaluated on surgical specimens.RESULTS:
Forty pts have been treated; 39 pts are assessable. TRG 3 and 4 were achieved in nine (23.1%) and three pts (7.7%) respectively; TRG 3-4 rate was 55% and 5.3% in case of high and low GCN, respectively (P 0.0016). Pts with K-ras mutated tumors had lower rate of high TRG 11% versus 36.7% (P 0.12). In pts with wild-type K-ras, TRG 3-4 rate was 58.8% versus 7.7% in case of high or low GCN, respectively (P 0.0012).CONCLUSIONS:
In pts with LARC, EGFR GCN is predictive of high TRG to cetuximab plus 5-FU radiotherapy. Moreover, our data suggest that a wild-type K-ras associated with a high EGFR GCN can predict sensitivity to cetuximab-based treatment.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias del Recto
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Protocolos de Quimioterapia Combinada Antineoplásica
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Genes ras
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Receptores ErbB
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Mutación
Tipo de estudio:
Prognostic_studies
Límite:
Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Ann Oncol
Asunto de la revista:
NEOPLASIAS
Año:
2009
Tipo del documento:
Article
País de afiliación:
Italia