Neoplasia 1 Flashcards
What is a neoplasm?
New growth
Cells unresponsive to normal growth controls
What is a hamartoma?
- A non neo plastic lump.
- Tissues are chaotically arranged in an APPROPRIATE site. (vs. choristoma which occurs in an inappropriate site)
- Will get massive increases in collagen, fibrous CT.
- Dilated apocrine glands.
What are two examples of non neoplastic lumps?
- Hamartoma
- Choristoma
What is a choristoma?
Give an example.
- A non neo plastic lump
- Tissue chaotically arranged but in an ABNORMAL SITE.
- ex: DERMOID
What is a dermoid?
- A type of choristoma.
- **Normal mature skin on the cornea: **
- Hard skin on the cornea because is hasn’t properly differentiated into corneal epithelium.
- Will get remnants of haired skin left on the cornea.
- Clinically will see the dog scratching at their eye, conjunctivitis, tear film.
What are some changes which may precede neoplasia?
- Pre neoplastic changes are reversible, arise in response to physiologic demands, injury or irritation and, if the inciting factors irs removed, will regress.
- Hypertophy: Remember hyperplasia can be physiolgoical and pathological so doesn’t always indicate neoplasia.
- Hyperplasia
- Metaplasia: Normal cuboidal epithelium becoming squamos.
- Dysplasia: lose organization of cells. Things become jumbled.
Gingival Hyperplasia;
Idiopathic breeds: Boxers over the age of 5. Great Danes, Dobies, Collies.
- Owner brings the pet in because of bleeding and the large bump in the mouth.
- The good thing about these growths is that they have little attachment to the gum and can be removed easily however they will REGROW so will have to keep remvoing them.
Sebaceous Hyperplasia:
Where are these usually found on the dog?
Hyperplastic or neoplastic?
These are dome shaped papillated masses that grow on the heads of animals.
Histopathology will show a duct, which indicates that its still hyperplastic and not neoplastic. Still functional.
Prosthatic Disease:
a Canine problem. What are the problems associted with this disease?
clinical signs?
- enlarged prostate could block the colon which sits above it causing a functional issue.
- difficulty defecating. Urination problems. Uremia.
What are tumor groupings?
- Mesenchymal: CT, fat, cartilage
- hematopoeitic
- lymphoid tissue - Epithelial
a. ectoderm: covering epithelium (skin)
b. mesoderm: solid organs (renal tubules, hepatocytes)
c. endoderm: linings (gut) - Nervous tissue (CNS/ PNS)
- Mixed
- Undifferentiated
What are the different mesenchymal tumors for CT, fat, blood, lymphatics?
Benign?
Malignant?
Benign:
- Fibroma
- Lipoma
- Hemangioma
- not recognized
Malignant:
- Fibrosarcoma
- Liposarcoma
- Hemangiosarcoma
- Lymphoma (lymphosarcoma)
What are the different epithelial tumors for skin and glands?
Benign?
Malignant?
Benign:
- Squamos papilloma
- Adenoma
Malignant:
- Squamos cell carcinoma
- Adenocarcinoma
What components of the tumor are essential for its survival?
- Parenchyma: this determines the biologic behavior of the tumor.
- Stoma: provides nutrition and physical support to the tumor. Essential for the tumors growth.
What are characteristics of benign tumors?
- Differentiation: well differentiated and structure is recognizable.
- Growth rate is slow. Progressive expansion. RARE mitotic figures.
- Local invasion: Benign tumors don’t have a true invasion. They have more of an expansile growth. (expanding rather than invading). Usually encapsulated.
- NO metastasis.
What are Characterisitcs of Malignant Tumors?
- Differentiaton: Lacking, structure is atypical. **(vs. benign where structure is recognizable, and well differentiated) **
- Growth rate: (variable) slow to rapid, erratic.
- -> Mitotic figures: abnormal mitotic figures are present **(these have an asymmetrical shape vs. normal mitotic figures which are symmetrical in shape) ** - Local invasion: infiltrative growth **(vs. benign which is expansive growth and non invasvie) **
- Metasis occurs frequently (none in benign tumors)
- cause death if untreated.
