neoplasia - whats cancer Flashcards
what is neoplasia?
a lesion resulting from the autonomous or relatively autonomous abnormal growth of cells which persists after initialising stimulus removed
-literally means new growth
- can be benign or malignant
what is tumour?
just means swelling
how do tumours arise?
due to accumulation of genetic alterations & epigenetic changes
what are neoplasms usually comprised of?
neoplastic cells & connective tissue stroma (vascular supply important)
- pseudo neoplasms & other abnormal growths also exist
what does malignant mean?
a neoplasm with potentially lethal, abnormal characteristics which has the ability to invade and metastasise
what does benign mean?
neoplasm which doesn’t have the ability to invade & metastasise (they’re not necessarily harmless)
what are the 4 factors to tell how bad a neoplasm is?
- differentiation (how different it looks from original tissue)
- rate of growth (look for rate of mitosis, necrosis etc)
- local invasion (how much it invades all the tissue & vessels around it)
- metastasis (is it eating into lymphatics & vessels - as if that happens more likely to spread through body)
what is differentiation in context of neoplasms?
extent to which neoplastic tissue resemble their corresponding normal tissue of origin
-> it has levels of well, moderate, poor and anaplastic (where well looks similar and anaplastic looks completely different)
- any level can be benign or malignant
- anaplastic may need special stains/molecular technique to diagnose
what are features of poorly differentiated tumours?
- nuclear pleomorphism (variability in nuclear size & shape)
- abnormal nuclear features
- increased mitotic activity
- loss of cellular polarity/order
- tumour giant cells
- necrosis
what are some examples of abnormal nuclear features in poorly differentiated tissues?
- high nuclear : cytoplasmic ratio
- clumped chromatin
- prominent nucleoli (dots in nucleus)
what is classification of the tumour?
name = grade & stage
what is grade in classification of tumour?
- measure of how differentiated the tumour appears
well = grade 1
moderately = grade 2
poorly = grade 3
what is stage in classification of tumour?
a measure of extent of spread of a tumour
= prognostication/therapeutic decisions
(lower the number = better for the patient)
what is metaplasia?
change in phenotype of differentiated cells, often response to chronic irritation
what is hypertrophy?
increased cell and thus organ size, often in response to increased workload e.g. cardiac hypertrophy
what is hyperplasia?
increased cell numbers in response to stimulus e.g. hormones / growth factors e.g. endometrial
what is dysplasia?
term used to describe confined neoplastic change (mostly epithelia)
what are some features of dysplasia?
- cytomorphological features of malignancy (all features - big nucleus, lots of mitosis →if all in epithelium but not invading then dysplasia, so not malignant yet but like gearing up)
- confined within basement membrane
- nuclear pleomorphism/architectural disruption
what is carcinoma- in situ?
really bad dysplasia
= cytomorphological features of malignancy but without invasion
= full thickness of epithelium
= basement membrane of dysplastic epithelium not penetrated (basement membrane separates blood/lymphatic vessels)
does dysplasia always lead to malignancy?
no, sometimes it can regress
what is the rate of growth like for malignant and benign neoplasms?
- malignant neoplasms are often fast growing
- benign neoplasms are usually slow growing
what are some features of rapid growth and why are they associated?
mitoses = because lots of cells are dividing rapidly
&
necrosis = because the tumour is growing so fast that the blood supply can’t keep up
what are some characteristics of benign tumours?
- cohesive & expansile (not invading but just squishing)
- localised
- don’t metastasise
- usually slow growth
- may be encapsulated (rim of compressed connective tissue = fibrous capsule)
what are some characteristics of malignant tumour?
- invasive
- penetrate organ walls/tissues/ epithelial surfaces
- next to metastases, invasiveness is the most reliable feature that differentiates malignant from benign tumours
what is metastasis?
spread of tumour to a site discontinuous from the source organ/tissue
what is growth rate for benign & malignant tumours?
benign = slow
malignant = fast
what is mitotic activity for benign & malignant tumours?
benign = low
malignant = high
what is differentiation for benign & malignant tumours?
benign = well
malignant = often poor
what is nuclear morphology for benign & malignant tumours?
benign = normal
malignant = pleomorphic
is there invasion for benign & malignant tumours?
benign = no
malignant = yes
what is border like for benign & malignant tumours?
benign = circumscribed and/or encapsulated
malignant = poorly defined/invasive
what is necrosis like for benign & malignant tumours?
benign = rare
malignant = common
what is ulceration like for benign & malignant tumours?
benign = rare
malignant = common
what is growth direction for benign & malignant tumours?
benign = exophytic
malignant = endophytic
are benign tumour always harmless?
no - some can be very locally destructive
e.g. meningioma, benign tumour of meninges, compressive effects in skull
what is histogenic classification & nomenclature?
based upon tissue of tumour origin
what are the different types of tissue of tumour origin?
epithelium:
- non glandular epithelia (protection)
- glandular epithelia (glands & ducts, secretion)
non epithelium:
- mesenchymal
- hematopoietic
- Neuroectodermal
- Germ cells
- Embryonal (blastomas)
- Mixed tumours
what is the suffix of benign tumours and what are the exceptions?
OMA
-> melanoma, lymphoma, seminoma, mesothelioma etc
what is adenoma?
type of benign tumour of glandular/secretory epithelium
(glands may or may not be present in the tumour)
what is papilloma?
benign tumour of non-glandular/surface epithelium (it actually describes fingerlike or warty projections but most benign non-glandular epithelial tumours do this)
what is squamous cell papilloma?
benign tumour of squamous epithelium (skin)
what is colonic adenoma?
benign tumour of glandular epithelium of the colon
how can you classify benign epithelial tumours?
first by if glandular or non-glandular (adenoma or papilloma) and then by name of cell type origin, epithelium source or cell type (e.g. squamous cell or colonic)
what is thyroid adenoma?
benign tumour of a glandular epithelium of thyroid
what is nomenclature for benign mesenchymal tumours?
cell of origin + OMA
what is prefix & benign nomenclature for smooth muscle?
prefix = leiomyo
benign nomenclature = leiomyoma
what is prefix & benign nomenclature for skeltal muscle?
prefix = Rhabdomyo
benign nomenclature = Rhabdomyoma
what is prefix & benign nomenclature for adipose tissue?
prefix = lipo
benign nomenclature = lipoma
what is prefix & benign nomenclature for blood vessel?
prefix = haemangio
benign nomenclature = haemangioma
what is prefix & benign nomenclature for bone?
prefix = osteo
benign nomenclature = osteoma
what is prefix & benign nomenclature for cartilage?
prefix = chondro
benign nomenclature = chrondroma
what is prefix & benign nomenclature for fibrous tissue?
prefix = fibro
benign nomenclature = fibroma
what do you call malignant epithelial tumours derived from glandular/ductural epithelium?
adenocarcinoma
what do you call malignant epithelial tumour derived from surface non-glandular epithelia?
carcinoma
what is squamous cell carcinoma?
malignant nomenclature for stratified squamous
what is basal cell carcinoma?
malignant nomenclature for basal cells of the skin
what is transitional cell carcinoma?
malignant nomenclature for transitional epithelium of the bladder
what is colonic adenocarcinoma?
malignant nomenclature for glandular epithelium of colon
what is breast adenocarcinoma?
malignant nomenclature for glandular epithelium of breast
what are malignant mesenchymal tumours called?
sarcomas (that’s the suffix - like OMA for benign mesenchymal and sarcoma for benign mesenchymal)
what is prefix and malignant nomenclature for smooth muscle?
prefix = leiomyo
malignant nomenclature = leiomyosarcoma
what is prefix and malignant nomenclature for skeletal muscle?
prefix = rhabdomyo
malignant nomenclature = rhabdomyosarcoma
what is prefix and malignant nomenclature for adipose tissue?
prefix = lipo
malignant nomenclature = liposarcoma
what is prefix and malignant nomenclature for blood vessels?
prefix = angio
malignant nomenclature = angiosarcoma
what is prefix and malignant nomenclature for bone?
prefix = osteo
malignant nomenclature = osteosarcoma
what is prefix and malignant nomenclature for cartilage?
prefix = chondro
malignant nomenclature = chondrosarcoma
what are teratomas? (other tumour type)
germ cell origin (gonads)
= contains cells representing ALL 3 germ layers (endoderm, mesoderm, ectoderm)
benign = teeth/hair/muscle/neural/cartilage
malignant = tissues more primitive
what are precursor cell tumours? (& examples)
= histological resemblance to embryological tissue in which arise
- RETINOBLASTOMA
- NEPHROBLASTOMA (WILMS)
- HEPATOBLASTOMA
(often occur in young patients)
what is mixed tumours?
epithelial & mesenchymal neoplasia
(single clone leads to both types of cells)
what is an example of a malignant mixed tumour?
carcinosarcoma (has parts of epithelial & mesenchymal tumour)
= makes challenging to treat
what is an example of benign mixed tumour?
ameloblastic fibroma
what is hamartoma?
- Non-neoplastic disordered overgrowth of normal tissue (benign)
- Indigenous to the site of occurrence (don’t invade or destroy)
- Developmental abnormalities
- Port wine stain
what is chrostoma?
- Benign normal tissue but seen in abnormal location
- E.g. normal (non-neoplastic) pancreas nodule in stomach, heterotropic rests (pancreas cells in weird places in body)
what are hematolymphoid malignancies?
Lymphoma = malignancy of T or B cell origin (often begins in lymph nodes but can arise in other places) - hodgkin vs non hodgkin
myeloma = malignancy of plasma cells
leukaemia = malignancy of white blood cells that begin in bone marrow
what are melanocytic neoplasms?
Melanoma
- Malignancy of melanocytes
- Cells which produce pigment in the skin
MELANOCYTIC NAEVUS
- Benign proliferation of melanocytes
