Cancer 1: cellular pathology Flashcards
Define metaplasia
Reversible change in which one adult cell (usually epithelial) is replaced by another adult cell type
Adaptive–like change with pH
(can be physiological-normal-as in puberty)\
eg: barrets oesophagus (acid reflux make squamous become columnar
Define neoplasia, tumour, malignancy
Abnormal, autonomous proliferation of cells, u responsive to normal growth mechanism
Divided between benign and malignant tumours
What is the difference bewteen benign and malignant tumours
Benign-does not invade-cannot metastase (cannot spread)
usually encapsulated-fibrious ridges demark it
Usually well differentiated (look like original tissue)
Slowly growing
normal mitosess
the first one is the absolute one, but the others are just way the can be recognised-not diagnostic
Beninign does not mean harmless-in meninges-block CSF, pituary-bad (press of bad structures or secrete)
or secrete something bad-insulinoma
Rarely fatal BUT can bleed, get infected, ruptire, torts
Define dysplasia
Abnormal growth pattern of growth i which soome cellular and architectural of malignancy are present BUT NON-INVASIVE (increased mitosis, weird mitosis, increased nuclear/cytoplasmic ratio, loss of uniformity of individual cells, loss of achitecture)
Pre-invasive stage-intact basement membrane
if can find it then-easy to treat and 100% no spread if treated
common in: cervix-hpv, bronchus (smoking), colon-UC, stomach-pernicious aneamia, oesophagus-acid reflux
(can get metaplasia leading to dysplasia)
What are dysplasia grades?
Low grade and high grade- (high grade closer to invasive cancer)
Low grade-tends to be more reversible and lesser chances of invasive
high grade tend to look darker as the nucleus is larger
Are benign tumours harmless?
Beninign does not mean harmless-in meninges-block CSF, pituary-bad (press of bad structures or secrete)
or secrete something bad-insulinoma
Rarely fatal BUT can bleed, get infected, ruptire, torts
What are the defining charactestics of malignant tumours?
Invade sourrounding tissues -main one
spread, no capsule, poorly differentiated, rapidly growing, abnormal mitoses
(again not all of them have that, but way to recognise them)
Define metastasis?
Discontinous growing colony of tumour cells, at some distance from the primary cancer
Can go via blood, lymph, large cavities
Usually follow venous and lymphatic drainage-so depends of the affected organ (like prostate-to aortic nodes)
Lymph node involvment makes it worse
What is a benign epithelial tumour?
On surface epithelium-papilloma (skin, bladder)
If of glandular epithelium-adenoma (stomach, thyroid, colon, kidney, pit, pancreas)
What is a carcinoma?
malignant tumour derives from epithelium-
Squamous carinima, adenocarcinoma, transitional cell carcinoma, basal cell carcinoma
What are benign soft tissue tumours? what are the malignant version?
depends on origin-
bone-oesteomas, lympomas-fat, leiomyomas-SMC, chondroma, rhabdomyoma (striated muscle), nerve shearth-malignant peripheral sheath tumour
Malignant version-sarcoma
(eg: osteosarcoma, liposarcoma, chondrosarcoma, etc)
What are leukemias and lymphomas?
Leukemias-tumours of bone marrow cells which circulate in blood
Lymphoma-tumours of lymphomas that are usually tissue based (lymph nodes, tonsils)
exceptions exist and both can spread to look like the other
What is a teratoma?
derived from germ cells-pluripotent cells-can develop in any 3 cell layers –can develop into any tissue of the body
tend to happen where you have germ cells
in males, nearly always malignant, in females, nearly always beninign (originate from gonades)
What is a hamartomas?
Localised overgrowths of cells/tissue native to the organ
cell are normal but architectural abnomal
common in children and stop growing when they do
-like weird looking bile ducts, bronchus, etc
How do you assess differentiation of tumours?
Check how much is resembles the tissue of origin-(poorly differentiated (bad) vs highly)
Check what is produces-is it producing what normal cell do (keratin, bile, mucin, hormones, etc)
grading systems in themselves are specific to the tumour and many many exist
if it shows NO differentiation-anaplastic carcinomas (resembles nothing we know)
What is the TNM scale?
Grade of a tumour describe its degree of differentiation
Stage of the tumour describe how far its spread
higher grade tends to correlate with higher stage
STAGE IS MORE IMPORTANT for prognosis
generic T-tumour, N-node, M-metastasis can be applied and individualised for all tumour sites-and is specific to all cancer
What are polyps?
Just extensions into the the lumen of a hollow organ
WHat are the 2 types of adenomas?
Tubular and villous
Tubular more common
What would make you worry about an adenma?
Grade-how differentiation (high grade worse)
Size (bigger the worse)
Types-Villous is worse-
all these have a higher chance of becoming carcinoma
What is the membrane being invaeded by adenoma to be considered cancer? Why does it matter?
Muscularis mucosae
No lymphatics before the submucosa-cant spread before arrives there
none in lamina propria
What is cancer stage and grade?
Stage-how far its spread -main one
Grade- how much it looks compared to original tissue
How is staged assessed?
Classification depends purely on the organ-generally how far its gone
But invasion of the wall is nearly always a good point
T2-through muscle
T3-not quite through end layer
t4-out of outer layer
bowel cancer uses Duke’s
What is a big clue for breast cancer when palpating if its cancer or adenoma? and other factors that are worrying?
If its fixed, that probably means its invaded tissue
Size is also an issue
age
asymetry-more likely to be cancerous
lymph-if you can feel them (lateral-auxillary nodes, if central-deep mediastanal) -more likely to be lateral
when cut it feels like a gritty pear because it has a lot of elastic tissue
Collagen around the tumour as response -finbrosis. angiogenesis
What epithelial tissues do you have in the breast?
Secretory units, and ductal units
So cancers can be lobular carcinomas or ductal carcinomas
lobulat tend bilateral and ductal tend to be unilateral-change mascetomy
need to understand normal structure to understand cancer
What does in situ mean for cancer?
In its place
actually means its high grade dysplasia (really high grade) but hasnt invaded yet-
really only happens in the breast
How are breast TNM assessesd?
SIze-2cm-T1, T2-5 T2, T3-over 5cm
T4-attatched to tissue
In colon cancer it was about how fat its gone through–
In breast its actually about size (with t4 being hybirid)
M-lymph nodes invades-difficult long scale-
What does pT2, cT2 and rT2 (and ypT2) mean?
T2-is stage 2 p is for pathology c-clinical r-radiology yp-after pre operative radiotherapy
What are the commonest type of skin cancer?
Squamous cell carcinoma, melanoma, basal cell carcinomas-big three-share sun
angio-sarcoma
rabdo-myoma-skeletal)
lymphoma
(can be fungal infection)
What is bowens disease/
Squamous cell carcinoma in tissue (skin cancers/dysplasia) tend to have names
often loss of acrhitecture (loss flat/oragnised)/nuclear ratio
lack of maturation fr skin