Lack of association between KRAS mutations and 18F-FDG PET/CT in Caucasian metastatic colorectal cancer patients.
BACKGROUND
Although Kirsten rat sarcoma (KRAS) gene mutational testing is essential for the optimal design of therapeutic strategies for colorectal cancer, it is not always feasible or reliable. In this retrospective study, we examined whether (18)F-Fluorodeoxyglucose positron-emission tomography/computed tomography ((18)F-FDG PET/CT) scans can serve as a surrogate examination for KRAS mutational testing.


METHODS
KRAS codon 12 and 13 mutational status was tested in 44 colorectal primary tumors and was compared with the (18)F-FDG PET/CT maximum standardized uptake value (SUVmax) values of the respective metastatic lesions. Glucose transporter-1 (GLUT1) mRNA levels were also measured in colorectal primary tumors.


RESULTS
No statistically significant correlation between (18)F-FDG PET/CT SUVmax values and KRAS mutation status was found (parametric t-test: p=0.4753; non-parametric Kruskal-Wallis test: p=0.51). This result cannot be attributed to the effect of differing GLUT1 mRNA levels, as shown by multivariate analysis.


CONCLUSIONS
Our study failed to promote (18)F-FDG PET/CT uptake as a surrogate examination for KRAS mutation testing.
Department of Medical Oncology, Papageorgiou Hospital, Nea Efkarpia Ring Road, PC 564 29, Thessaloniki, Greece. dkrikelis@gmail.com.
Dimitrios
D
Krikelis
Evangelia
E
Skoura
Vassiliki
V
Kotoula
Phivi
P
Rondogianni
Nikoletta
N
Pianou
Alexandros
A
Samartzis
Ioannis
I
Xanthakis
George
G
Fountzilas
Ioannis E
IE
Datseris
D000328:Adult; D000368:Aged; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics*; D004252:DNA Mutational Analysis / Q000379:methods*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009154:Mutation; D049268:Positron-Emission Tomography; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D019275:Radiopharmaceuticals; D060888:Real-Time Polymerase Chain Reaction; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D018631:ras Proteins / Q000235:genetics*
C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins
GLUT1; KRAS mutations; PET/CT; SUVmax; colorectal cancer