title: Delineation of the infrequent mosaicism of KRAS mutational status in metastatic colorectal adenocarcinomas.
abstract: This study addresses the extent of the heterogeneity of KRAS status, present in a minority of metastatic colorectal carcinomas (mCRCs), on the basis of a thorough analysis of surgical resection specimens. Eighteen patients with mCRC were included. KRAS mutations (exon 2, codons 12 and 13) were determined using PCR and subsequent direct sequencing. This analysis included primary tumours (n=21), synchronous (n=10) and metachronous (n=18) matched metastases, and pelvic recurrence (n=1). Heterogeneity of KRAS status consisted in KRAS mutated in (i) the primary tumour but not in its synchronous metastasis, (ii) the metastasis but not in the primary tumour, (iii) the pelvic recurrence but not in the primary tumour, (iiii) some metastases and not in others from the same patient. Finally, the KRAS status varied among different areas of the same metastatic focus. This study defines the concept of KRAS mosaicism that affects a minority of mCRCs.
authors.affiliation: Université de Nantes, Faculté de Médecine de Nantes, EA 4273 Biometadys, Nantes, France. celine.bossard@chu-nantes.fr
authors.forename: Céline
authors.initials: C
authors.lastname: Bossard
authors.forename: Sébastien
authors.initials: S
authors.lastname: Küry
authors.forename: Philippe
authors.initials: P
authors.lastname: Jamet
authors.forename: Hélène
authors.initials: H
authors.lastname: Senellart
authors.forename: Fabrice
authors.initials: F
authors.lastname: Airaud
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Ramée
authors.forename: Stéphane
authors.initials: S
authors.lastname: Bézieau
authors.forename: Tamara
authors.initials: T
authors.lastname: Matysiak-Budnik
authors.forename: Christian L
authors.initials: CL
authors.lastname: Laboisse
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Mosnier
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000556:secondary / Q000601:surgery; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000032:analysis; D006801:Humans; D008875:Middle Aged; D009030:Mosaicism; D009154:Mutation; D009364:Neoplasm Recurrence, Local; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics*
chemical_list: D004273:DNA, Neoplasm; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins