KRASmutation in patients with metastatic colorectal cancer does not preclude benefit from oxaliplatin-or irinotecan-based treatment.
Fluoropyrimidine-based chemotherapy plus antibody therapy is currently the standard first-line treatment for metastatic colorectal cancer (mCRC). In this study, we investigated the hypothesis that mutations in several of the targeted oncogenes are correlated with treatment outcomes in mCRC patients receiving different first-line regimens. Our study included a total of 194 patients who had undergone various forms of first-line chemotherapy. TheKRAS,BRAF,PIK3CA,NRASandAKT1mutational status of the tumors was assessed and the association between mutational status and treatment outcome was evaluated. The median progression-free survival (mPFS) of the wild-type and mutatedKRASsubgroups that had received oxaliplatin-based treatment was 8.6 and 6.8 months, respectively (P=0.41), whereas the mPFS of the wild-typeKRAS,BRAF,PIK3CA,NRASandAKT1subgroups and that of their respective mutant subgroups was 9.7 and 7.2 months, respectively (P=0.10). The mPFS of the wild-type and mutatedKRASsubgroups that had received irinotecan-based treatments was 7.7 and 9.7 months, respectively (P= 0.43). The mPFS of the wild-typeKRAS,BRAF,PIK3CA,NRASandAKT1subgroups and that of their respective mutant subgroups was 7.1 and 10.0 months, respectively (P=0.76). Our data indicated that mCRC patients with activation ofKRAS,BRAF,PIK3CA,NRASandAKT1mutations, even those being treated with oxaliplatin- and irinotecan-based regimens as first-line treatment, may benefit from cytotoxic drug therapy.
Department of Clinical Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi 980-8575;
Hiroshi
H
Soeda
Department of Clinical Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi 980-8575;
Hideki
H
Shimodaira
Department of Pathology, Tohoku University Hospital, Sendai, Miyagi 980-8574;
Mika
M
Watanabe
Department of Medical Oncology, Sendai Medical Center, Sendai, Miyagi 983-8520;
Takao
T
Suzuki
Department of Clinical Oncology, South Miyagi Medical Center, Ogawara, Miyagi 989-1253, Japan.
Makio
M
Gamo
Department of Clinical Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi 980-8575;
Masanobu
M
Takahashi
Department of Clinical Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi 980-8575;
Keigo
K
Komine
Department of Clinical Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi 980-8575;
Shunsuke
S
Kato
Department of Clinical Oncology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi 980-8575;
Chikashi
C
Ishioka
FOLFIRI; FOLFOX; KRAS; colorectal cancer