title: Morphological and molecular heterogeneity in colorectal neoplasms with K-RAS mutation. A report of two cases.
abstract: Approximately forty percent of colorectal cancers (CRC) are characterized by activating mutations of the K-RAS gene. Determination of K-RAS mutational status as a predictive marker for anti-EGFR therapy is usually based on the assumption of intratumoral homogeneity. We present two cases of CRC in which morphologically distinct tumor components were associated with different activating mutations of K-RAS in one patient and a mutated and a non-mutated portion in the second patient, as demonstrated by laser microdissection and consecutive molecular analyses.
authors.affiliation: Institute of Pathology, Krankenhaus Barmherzige Schwestern Linz, Seilerstätte 4, A-4020 Linz, Austria. hans-christian.boesmueller@bhs.at
authors.forename: Hans
authors.initials: H
authors.lastname: Bösmüller
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kranewitter
authors.forename: Gerald
authors.initials: G
authors.lastname: Webersinke
authors.forename: Holger
authors.initials: H
authors.lastname: Rumpold
authors.forename: Margit
authors.initials: M
authors.lastname: Hackl
authors.forename: Falko
authors.initials: F
authors.lastname: Fend
mesh_terms: D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D004252:DNA Mutational Analysis; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D042282:Microdissection; D008875:Middle Aged; D058990:Molecular Targeted Therapy; D009154:Mutation; D010641:Phenotype; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics*
chemical_list: D000970:Antineoplastic Agents; C117307:KRAS protein, human; D047428:Protein Kinase Inhibitors; D011518:Proto-Oncogene Proteins; C512478:EGFR protein, human; D066246:ErbB Receptors; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins