8. Oral facial & bone neoplasms Flashcards
what is neoplasia?
new growth
what is a neoplasm?
- an abnormal growth that exceeds normal
tissue - It is uncoordinated and persists after the cessation of the stimulus that caused it
what categories can neoplasia be divided into?
- malignant
- benign
characteristics of benign neoplasia
(under a microscope)
1 - differentiation
2 - rate of growth
3 - local invasion
=(refers to the way that the growth affects the surrounding tissue)
4 - metastasis
=(spread from sight of origin to distant sights around the body)
1
- Well differentiated
- Looks like tissue of origin with
organised structure
2
- Usually slow
3
- Normally well circumscribed with no invasion (usually capsule around, hence pushes tissue away instead of infiltrating tissues)
4
- Absent
- don’t spread
characteristics of malignant neoplasia
(under a microscope)
1 - differentiation
2 - rate of growth
3 - local invasion
4 - metastasis
1
- Un-differentiated or poorly differentiated
- Looks different to tissue of origin
with disorganised structure
- cells may vary in size, may not be adherent to each other, may migrate in unusual ways etc
2
- Likely to be rapid
3
- Invasive with poorly defined margin
- not well encapsulated, irregular
- infiltration into surrounding tissue
4
- Common
- spread
- can happen EG via lymphatic or via blood stream
- EG head + neck cancer, tends to metastasise by the lymphatic and spread to other places EG lungs
Benign VS malignant characteristics (diagram)
BENIGN
- capsule around outside
- cells look similar
- evenly spaced cells
- overlying tissue being pushed away as is lesion is expanding
- no signs of invasion
MALIGNANT
- cells of varying size
- outer layer not even and not encapsulated
- invasion as cells are moving downwards into surrounding tissue
- areas of necrosis
why can there be areas of necrosis in a malignant neoplasm?
- as rate of division of cells is so high, it actually outstrips its blood supply, hence parts of lesion and cells within lesion are often starved of blood
- hence get area of necrotic tissue within lesion
common benign oral neoplasias?
(hint 9)
- most end in ‘oma’ hence hit indicating that it’s benign BUT all don’t
- Haemangioma
- Lipoma
- Fibroepithelial polyp
- Papilloma
- Naevus
- pyogenic granuloma
- ameloblastoma
- pleomorphic adenoma
- bony exostosis
what is Heamangioma?
- Benign vasoformative neoplasm
- formed from either capillaries OR blood vessels
- described as either Capillary or cavernous haemangioma if it has large blood filled spaces within it
- Blanch on pressure
(full of blood so if press on it, will go paler/ whiter) - can be performed by microscope slide
- May cause troublesome bleeding or cosmetic defect
- Treat by cryotherapy / sclerotherapy / excision
Haemangioma
- in image = cryotherapy
- if you were to remove it surgically it would be quite a large area so cryotherapy done
- sometimes has to be repeated and sometimes doesn’t work so surgery needed
what is a lipoma
- Benign neoplasm of adipose tissue
- Occur anywhere there is subcutaneous / subdermal fat (EG within oral cavity, on face, neck etc
- Soft yellow discolouration in oral mucosa or pink with normal overlying mucosa / skin
- on skin usu feel small, soft, mobile lump
- Treat with surgical excision as have capsule around outside
lipoma
what is Fibroepithelial Polyp (FEP)?
Most common benign epithelial tumour of oral cavity
* Painless flat or pedunculate lesion
* Uncommon before age 30
* Inflammatory hyperplasia due to chronic irritation eg cheek biting, orthodontic appliance, etc
* Local surgical excision if troublesome
* can be left if no trouble
Fibroepithelial Polyp (FEP)
- smooth surface
- surrounding mucosa looks normal
what is a papilloma?
- Benign proliferating lesion caused by human papilloma virus (hpv)
- Most common between age 30 - 50
- HPV strains 6 and 11 (not cancer inducing type 16 + 18 )
- Soft palate and tongue most common
- Local surgical excision or cryotherapy if troublesome or if patient worried