title: Qualitative histological differences between transplacentally-induced lung tumors in young and aging mice.
abstract: Transplacentally-induced lung tumors arising in BALB/c mice 38-45 weeks old (late crop) were significantly larger and more invasive of the surrounding lung parenchyma than were the tumors appearing at 10-36 weeks (early crop). The late-crop tumors were also somewhat more papillary and heterogeneous. Development of the 2 crops of tumors from different cell types of origin is postulated. A specific association of lymphocytes with the pleural surfaces of some tumors was noted and this association was significantly more likely for tumors invading the parenchyma than for non-invasive ones.
mesh_terms: D000236:Adenoma / Q000139:chemically induced / Q000473:pathology; D000367:Age Factors; D000818:Animals; D005260:Female; D005333:Fetus / Q000187:drug effects*; D005865:Gestational Age; D008175:Lung Neoplasms / Q000139:chemically induced / Q000276:immunology / Q000473:pathology*; D008214:Lymphocytes / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000139:chemically induced / Q000276:immunology / Q000473:pathology; D011247:Pregnancy; D014520:Urethane
chemical_list: D014520:Urethane