Neoplasia 1 Flashcards
what is a neoplasm
an abnormal mass of tissue
comment on the growth of neoplasms
uncoordinated and exceeds that of normal tissues, growth persists after removal of the stimuli that initiated the change
what are the two class of neoplasia?
benign and malignant
what does histogenesis mean?
tissue of origin
what is the growth pattern for benign tumours?
expansion, may be encapsulated, localised
what is the growth pattern for malignant tumours?
invasion/infiltration, no capsule, metastasis
what is the growth rate for benign tumours?
slow
what is the growth rate for malignant tumours?
more rapid but variable
what is the histology of benign tumours?
resembles tissue of origin but with differentiation, uniform cell/nuclear shape and size, few mitoses
what is the histology of malignant tumours?
variable resemblance to tissue of origin, cellular and nuclear pleomorphism, many mitoses, abnormal
what are the clinical effects of benign tumourd?
lump/pressure/obstruction depending on site and size, increased/decreased hormone secretion, treat by local excision
what are the clinical effects of malignant tumours?
local pressure, infiltration and destruction, increased/decreased secretion, local excision and chemotherapy or radiation if metastases present
what are the effects of benign tumours?
palpable lump, pressure, obstruction, function - hormone
what does the effect of benign tumours depend on?
site, size and tumour type
what is a pleomorphic adenoma?
benign salivary gland tumour
what is classification 1 of tumours?
clinical behaviour, benign vs malignant
what is classification 2 of tumours?
histogenesis
what is a benign tumour of the squamous epithelium called?
papilloma
what is a benign tumour of the glandular epithelium e.g. salivary called?
adenoma
what is a malignant tumour of the squamous epithelium called?
squamous cell carcinoma
what is a malignant tumour of the glandular epithelium called?
adenocarcinoma
what word indicates that an epithelial tumour is malignant?
carcinoma
what type of tissue is the word carcinoma related to?
epithelium
what type of tissue is the word sarcoma related to?
connective tissue
what is a benign tumour of the smooth muscle called?
leiomyoma
what is a benign tumour of the fibrous tissue called?
fibroma
what is a benign tumour of the bone tissue called?
osteoma
what is a benign tumour of the cartilage called?
chondroma
what is a benign tumour of the fatty tissues called?
lipoma
what is a benign tumour of the blood vessels called?
angioma
what is a malignant tumour of the smooth muscle called?
leiomyosarcoma
what is a malignant tumour of the fibrous tissue called?
fibrosarcoma
what is a malignant tumour of the bone called?
osteosarcoma
what is a malignant tumour of the cartilage called?
chondrosarcoma
what is a malignant tumour of the fat called?
liposarcoma
what is a malignant tumour of the blood vessel called?
angiosarcoma
what is a benign tumour of the melanocytes called?
naevus (mole)
what is a benign tumour of the germ cells called?
benign teratoma
what is a malignant tumour of the lymphoid tissues called?
lymphoma
what is a malignant tumour of the haemopoietic tissues called?
leukaemia
what is a malignant tumour of the melanocytes called?
melanoma
what is a malignant tumour of the germ cells called?
malignant teratoma
what are the two factors of carcinogenesis?
environmental and genetic
what are the carcinogens for benign tumours?
may be inherited factors, viruses
what are the carcinogens for malignant tumours?
chemical agents, physical agents, viruses
what are the types of chemical carcinogens?
smoking polycyclic hydrocarbons including tars, diet, drugs, alcohol, asbestos
what are the two stages of chemical carcinogenesis?
initiation and promotion
what is initiation?
permanent DNA damage (mutations), when a carcinogen induces a genetic change resulting in a neoplastic potential
what is promote
agent promotes proliferation, another factor stimulates the initiated cell for division
what is a latent period?
time from promotion to clinical tumour
what is progression?
additional mutations resulting in malignancy
what stage of chemical carcinogenesis is irreversible
initiation and progression (if oncogenetic)
what stage of chemical carcinogenesis is reversible?
promotion and progression (if genetic)
what is included in physical carcinogenesis?
ionising radiation which damages DNA causing mutations, radioactive metals and gases. UV light (damage DNA, skin cancer)
what tumours does radium cause?
bone and bone marrow
what tissues are the most sensitive?
those where the cells are rapidly renewed (labile)
what is the most sensitive tissue?
embryonic tissue
what is the least sensitive tissue?
muscle and nerve tissue
what is included in viral carcinogenesis?
DNA viruses and RNA viruses
comment on DNA viruses and carcinogenesis
they are more common, viral DNA is inserted into host DNA
how do RNA viruses work?
they are reverse transcribed and then inserted
what viruses causes Burkitt’s lymphoma and nasopharyngeal carcinoma
Epstein-Barr virus
what viruses cause hepatocellular carcinomas?
hep B/C
what virus causes cervical and oropharyngeal carcinoma?
HPV
what contributes to the aetiology of oral cancer?
tobacco (smoking or chewin), betel quid, alcohol, diet and nutrition, oral hygiene, viruses (HPV), immunodeficiency, socioeconomic factors, GORD
what are potentially malignant disorders of the oral mucosa indicators of?
the risk of likely future malignancies occurring in oral mucosa
what is leukoplakia?
white patch that cannot be rubbed off or attributed to any other cause, potentially malignant lesion
what is dysplasia?
abnormality confined to epithelium, underlying tissue is not affected
what squamous tissues can dysplasia affect
oral and cervix
give examples of glandular dysplasia
barrett’s oesophagus and colonic polyps
what transitional tissue does dysplasia affect?
bladder
what type of tissue has the potential to become malignant?
tissue that shows dysplasia
how is dysplasia identified?
through changes in the cells appearance and arrangement
what does cellular atypia mean?
changes in the cells appearance and arrangement