Biomaterial Database

Spontaneous skin neoplasms in aged Sprague-Dawley rats. 1992

G M Zwicker, and R C Eyster, and D M Sells, and J H Gass

Toxicology Department, Marion Merrell Dow, Inc., Indianapolis, Indiana 46268.

A total of 93 tumors of the epidermis, its appendages, and dermis were observed in 1,433 (717 males, 716 females) rats employed in oncogenicity studies over a 2-yr period. Mammary gland neoplasms will be reported separately. Fifty-seven (61.3%) were epithelial with 49 in males and 8 in females. Keratoacanthoma was the most frequent epithelial neoplasm in males (22) followed by squamous cell carcinoma (11) and papilloma (5). Sebaceous gland neoplasms seen in males (5) included both adenomas (3) and carcinomas (2). In males, there were also 3 trichoepitheliomas, 1 pilomatricoma, 1 basal cell tumor, and 1 malignant melanoma. Of the 8 epithelial neoplasms in females, there were 3 squamous cell carcinomas, 2 keratoacanthomas, and 1 each basal cell tumor, malignant melanoma, and trichoepithelioma. There were 21 mesenchymal neoplasms in males and 15 in females. The most frequent neoplasm was fibroma (7 males, 8 females) followed by lipoma (7 males, 4 females) and fibrosarcoma (4 males, 3 females). One male had a liposarcoma and 2 males each had hemangioma. The total neoplasm incidence of 70/717 (9.8%) in males and 23/716 (3.2%) in females showed that skin neoplasms were 3 time more common in males than in females. Epithelial neoplasms of the skin were 6 times more common in males than in females. Males were more than twice as likely to have epithelial rather than mesenchymal skin neoplasms whereas the reverse was seen in females.

UI	MeSH Term	Description	Entries
D007636	Keratoacanthoma	A benign, non-neoplastic, usually self-limiting epithelial lesion closely resembling squamous cell carcinoma clinically and histopathologically. It occurs in solitary, multiple, and eruptive forms. The solitary and multiple forms occur on sunlight exposed areas and are identical histologically; they affect primarily white males. The eruptive form usually involves both sexes and appears as a generalized papular eruption.	Keratoacanthomas
D008067	Lipoma	A benign tumor composed of fat cells (ADIPOCYTES). It can be surrounded by a thin layer of connective tissue (encapsulated), or diffuse without the capsule.	Fatty Tumor,Hibernoma,Lipoma, Pleomorphic,Atypical Lipoma,Lipomata,Lipomatosis, Multiple,Atypical Lipomas,Fatty Tumors,Hibernomas,Lipoma, Atypical,Lipomas,Lipomas, Atypical,Lipomas, Pleomorphic,Lipomatas,Lipomatoses, Multiple,Multiple Lipomatoses,Multiple Lipomatosis,Pleomorphic Lipoma,Pleomorphic Lipomas,Tumor, Fatty,Tumors, Fatty
D008297	Male		Males
D008648	Mesoderm	The middle germ layer of an embryo derived from three paired mesenchymal aggregates along the neural tube.	Mesenchyme,Dorsal Mesoderm,Intermediate Mesoderm,Lateral Plate Mesoderm,Mesenchyma,Paraxial Mesoderm,Dorsal Mesoderms,Intermediate Mesoderms,Lateral Plate Mesoderms,Mesenchymas,Mesoderm, Dorsal,Mesoderm, Intermediate,Mesoderm, Lateral Plate,Mesoderm, Paraxial,Mesoderms, Dorsal,Mesoderms, Intermediate,Mesoderms, Lateral Plate,Mesoderms, Paraxial,Paraxial Mesoderms,Plate Mesoderm, Lateral,Plate Mesoderms, Lateral
D010212	Papilloma	A circumscribed benign epithelial tumor projecting from the surrounding surface; more precisely, a benign epithelial neoplasm consisting of villous or arborescent outgrowths of fibrovascular stroma covered by neoplastic cells. (Stedman, 25th ed)	Papilloma, Squamous Cell,Papillomatosis,Papillomas,Papillomas, Squamous Cell,Papillomatoses,Squamous Cell Papilloma,Squamous Cell Papillomas
D002280	Carcinoma, Basal Cell	A malignant skin neoplasm that seldom metastasizes but has potentialities for local invasion and destruction. Clinically it is divided into types: nodular, cicatricial, morphaic, and erythematoid (pagetoid). They develop on hair-bearing skin, most commonly on sun-exposed areas. Approximately 85% are found on the head and neck area and the remaining 15% on the trunk and limbs. (From DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1471)	Carcinoma, Basal Cell, Pigmented,Epithelioma, Basal Cell,Rodent Ulcer,Ulcer, Rodent,Basal Cell Carcinoma,Basal Cell Carcinomas,Basal Cell Epithelioma,Basal Cell Epitheliomas,Carcinomas, Basal Cell,Epitheliomas, Basal Cell,Rodent Ulcers,Ulcers, Rodent
D004848	Epithelium	The layers of EPITHELIAL CELLS which cover the inner and outer surfaces of the cutaneous, mucus, and serous tissues and glands of the body.	Mesothelium,Epithelial Tissue,Mesothelial Tissue,Epithelial Tissues,Mesothelial Tissues,Tissue, Epithelial,Tissue, Mesothelial,Tissues, Epithelial,Tissues, Mesothelial
D005260	Female		Females
D005350	Fibroma	A benign tumor of fibrous or fully developed connective tissue.	Fibromatosis,Fibromyxoma,Myxofibroma,Fibromas,Fibromatoses,Fibromyxomas,Myxofibromas
D005354	Fibrosarcoma	A sarcoma derived from deep fibrous tissue, characterized by bundles of immature proliferating fibroblasts with variable collagen formation, which tends to invade locally and metastasize by the bloodstream. (Stedman, 25th ed)	Fibrosarcomas