title: Distinct clinicopathologic characteristics of lung mucinous adenocarcinoma with KRAS mutation.
abstract: Primary mucinous adenocarcinomas are uncommon, and their pathogenesis remains unclear. We recently reported the clinicopathologic characteristics of surgically resected mucinous adenocarcinoma, including the frequent involvement of the left and lower lung and absence of central fibrosis. The present study attempted to clarify the pathogenesis of mucinous adenocarcinoma based on KRAS mutation status. We selected 45 mucinous adenocarcinoma cases from among 2474 surgically resected primary lung adenocarcinomas. Of these, 22 had a KRAS mutation (48.9%), whereas only 7 (15.6%) had an epidermal growth factor receptor mutation, and 2 cases had both mutations. The mucinous adenocarcinomas with KRAS mutations were located in the lower lung lobe significantly more often (P < .05) than were tumors without KRAS mutation. The mucinous adenocarcinoma cases with KRAS mutations also had a significantly lower frequency of nuclear atypia (P < .05). We compared the degree of immunostaining for matrix metalloproteinase-7 (MMP-7), laminin-5, and geminin in the mucinous adenocarcinoma with and without KRAS mutation. The proportion of geminin-positive cells was lower among the cases with a mutation than among those without (0.7% versus 2.1%; P < .05). No significant differences in the extent of staining of the other markers were observed between the groups. The current study clearly demonstrated that mucinous adenocarcinomas with KRAS mutations have clinicopathologic characteristics different from those of mucinous adenocarcinoma without such mutations.
authors.affiliation: Pathology Division, Research Center for Innovative Oncology, National Cancer Center Hospital East, Kashiwa, 277-8577 Chiba, Japan; Division of Thoracic Oncology, National Cancer Center Hospital East, Kashiwa, 277-8577 Chiba, Japan; Cancer Physiology Project, Research Center for Innovative Oncology, National Cancer Center Hospital East, Kashiwa, 277-8577 Chiba, Japan.
authors.forename: Hideomi
authors.initials: H
authors.lastname: Ichinokawa
authors.forename: Genichiro
authors.initials: G
authors.lastname: Ishii
authors.forename: Kanji
authors.initials: K
authors.lastname: Nagai
authors.forename: Akikazu
authors.initials: A
authors.lastname: Kawase
authors.forename: Junji
authors.initials: J
authors.lastname: Yoshida
authors.forename: Mitsuyo
authors.initials: M
authors.lastname: Nishimura
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Hishida
authors.forename: Naomi
authors.initials: N
authors.lastname: Ogasawara
authors.forename: Katsuya
authors.initials: K
authors.lastname: Tsuchihara
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ochiai
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000368:Aged; D000369:Aged, 80 and over; D015815:Cell Adhesion Molecules / Q000378:metabolism; D066246:ErbB Receptors / Q000235:genetics; D005260:Female; D064248:Geminin / Q000378:metabolism; D006801:Humans; D008168:Lung / Q000378:metabolism / Q000473:pathology*; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008297:Male; D020783:Matrix Metalloproteinase 7 / Q000378:metabolism; D008875:Middle Aged; D009154:Mutation; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics*; D000097794:Kalinin
chemical_list: D015815:Cell Adhesion Molecules; D066246:ErbB Receptors; D064248:Geminin; D020783:Matrix Metalloproteinase 7; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins; D000097794:Kalinin; C117307:KRAS protein, human
keywords: Epidermal growth factor receptor (EGFR); KRAS; Mucinous adenocarcinoma