Transition between morule-like and solid components may occur in solid-predominant adenocarcinoma of the lung: report of 2 cases with EGFR and KRAS mutations.
A limited number of pulmonary adenocarcinoma cases with morule-like components have been described to date, and the most frequent histological subtype is papillary-predominant adenocarcinoma. Occasionally, this type of adenocarcinoma is associated with solid-predominant adenocarcinoma. EGFR mutations are predominant in adenocarcinoma with morule-like components, followed by ALK rearrangements. Herein, we present 2 cases of solid-predominant adenocarcinoma with morule-like components harboring either an EGFR or KRAS mutation. This KRAS-mutant case is the first to be associated with morule-like components, to the best of our knowledge. Both cases showed transition between micropapillary and morule-like components. Transition between morule-like and solid components was also observed in both cases. Although a few cases of solid-predominant adenocarcinoma have been shown to harbor morule-like components, this type of transition has not been previously well described. We surmised that the solid components of some EGFR-mutant adenocarcinomas might be derived from morule-like components.
Department of Pathology, Shizuoka Saiseikai General Hospital Shizuoka, Japan.
Shogo
S
Tajima
Department of Pathology, Fujieda Municipal General Hospital Shizuoka, Japan.
Kenji
K
Koda
D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology*; D000077192:Adenocarcinoma of Lung; D000368:Aged; D066246:ErbB Receptors / Q000235:genetics*; D018773:Genes, erbB-1 / Q000235:genetics; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics*
C117307:KRAS protein, human; C512478:EGFR protein, human; D066246:ErbB Receptors; D016283:Proto-Oncogene Proteins p21(ras)
EGFR; KRAS; Lung; adenocarcinoma; morule; solid