A method for identifying the presence or absence of a Kras genetic aberration in a microvesicle from a subject, wherein the Kras genetic aberration encodes a Kras mutation of G12D, the method comprising the steps: a) isolating one or more microvesicles from a body fluid sample of a subject after filtering the body fluid sample to remove cell contamination; b) extracting DNA and/or RNA from the one or more microvesicles; and c) identifying the presence or absence of the Kras genetic aberration in the extracted DNA and/or RNA by: i) sequencing nucleic acids encoding Kras present in the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; ii) performing allele specific PCR of one or more nucleic acids encoding the Kras mutation on the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; iii) hybridizing probes specific for nucleic acid encoding the Kras mutation to the extracted DNA and/or RNA and detection of probes specifically hybridized to the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; or iv) performing quantitative PCR (qPCR) of one or more nucleic acids encoding the Kras mutation on the extracted DNA and/or RNA thereby identifying the presence or absence of the Kras genetic aberration. a) isolating one or more microvesicles from a body fluid sample of a subject after filtering the body fluid sample to remove cell contamination; b) extracting DNA and/or RNA from the one or more microvesicles; and c) identifying the presence or absence of the Kras genetic aberration in the extracted DNA and/or RNA by: i) sequencing nucleic acids encoding Kras present in the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; ii) performing allele specific PCR of one or more nucleic acids encoding the Kras mutation on the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; iii) hybridizing probes specific for nucleic acid encoding the Kras mutation to the extracted DNA and/or RNA and detection of probes specifically hybridized to the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; or iv) performing quantitative PCR (qPCR) of one or more nucleic acids encoding the Kras mutation on the extracted DNA and/or RNA thereby identifying the presence or absence of the Kras genetic aberration. i) sequencing nucleic acids encoding Kras present in the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; ii) performing allele specific PCR of one or more nucleic acids encoding the Kras mutation on the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; iii) hybridizing probes specific for nucleic acid encoding the Kras mutation to the extracted DNA and/or RNA and detection of probes specifically hybridized to the extracted DNA and/or RNA to thereby identify the presence or absence of the Kras genetic aberration; or iv) performing quantitative PCR (qPCR) of one or more nucleic acids encoding the Kras mutation on the extracted DNA and/or RNA thereby identifying the presence or absence of the Kras genetic aberration.