tumour classification Flashcards
what do most tumour names include?
the suffix ‘oma’
how do we subclassify tumours?
on a variety of things
benign or malignant
primary or secondary
histological origin - the tissue type that the tumour has originated from
why do we classify tumours?
it outlines treatment options
determines prognosis
characterises the lesions behaviours
what are the four types of tissue and extra type that make up histological classification?
epithelium connective tissue muscle nervous tissue extra is marrow
what is the most common histological tissue origin?
epithelial
what is epithelial tissue and an example?
it is the tissue that lines surfaces and an example is mesenchymal
what is connective tissue?
bone, cartilage, ligaments, tendons and fat
where do haematological malignancies arise from?
different components that make up the blood - marrow
how do we name benign epithelial tumours?
if it is secretory glandular then will be an ademona and if it is non secretory then is a papilloma
what are the types of simple epithelial cell?
simple squamous, cuboidal, columnar or pseudostratified
what are the types of stratified epithelial cell?
transitional, cuboidal, columnar, squamus or keratinised squamous
how would colonic crypts be identified in histology and why?
they are white spots and this is because they contain mucus too lubricate the stools
what is an example of a non secretory benign epithelial tumour?
skin lesions of squamous epithelium or urothelial cell
how are tumours then further identified from papilloma and adenoma?
the cell type of origin is identified - glandular tissue of origin for adenomas such as colonic or thyroid
why is a urothelial cell papilloma non secretory?
it is in the bladder but only stores urine does not secrete
what are malignant epithelial tumours?
carcinomas - secretory would be an adenocarcinoma
`why is it important to specify the epithelium of adenocarcinoma?
they can arise from glandular epithelium such as lung adenocarcinomas or colorectal
how do you name non glandular carcinomas?
specify the epithelial cell types such as basal cell carcinoma
what are the two most common types of epithelial carcinoma?
basal cell or squamous cell carcinoma
what is dysplasia?
it is disordered maturation and nuclei changes
what is a carcinoma in situ?
it is a carcinoma that has not invaded through the basement membrane but will invade if no treatment
what precedes carcinoma in situ?
dyplasia - becomes dysplastic before invasion
where is carcinoma in situ common?
in the cervix
how do we name mesenchymal tumours?
they are also ‘omas’ but with benign it will have a prefix of the tissue of origin and same with malignant but this is sarcomna
what are the prefixes for smooth and skeletal muscle, adipose, blood vessels, bone, cartilage and fibrous?
smooth - leiomyo skeletal - rhabdomyo adipose - lipo blood vessels - angio bone - osteo cartilage - chondro fibrous - fibro
what is a mole?
it is an exception to the naming rules - it is a benign melanocytic lesion/melanocytic naevus. There are many subtypes and most are benign but some do have malignant potential
what is another exception to naming rules?
malignant melanoma - this is in situ but cannot be left as is pre-invasive. It is dark, irregular and has different textures, and the melanoma is under the epidermis
what is a mesothelioma?
it is an exception to the naming rules - it is a tumour of the pleura that lines the lung. There is no benign counter parts and they are mainly fatal
what are common types of tumours the CNS?
meningioma (tumour in meninges lining the brain), glioma (in the glial supporting cells) and pituitary tumours
where do neurons form tumours?
in the PNS but generally not the CNS
why do brain tumours cause problems?
due to the restricted space within the skull
does tumour metastasis happen in the brain?
often tumours from elsewhere will metastasise to the brain but it is uncommon for brain tumour to metastasise elsewhere due to the blood brain barrier
where do germ cell tumours arise from?
the germ cells that are found in the gonads (ovaries and testes).
why might a tumour occur in the midline?
germ cells originate in the midline and then migrate to the gonads and therefore if there are any left in the midline they can form a tumour
what is germ cell nomenclature based on?
the gonad or the differentiation
what is a seminoma and a dysgerminoma?
seminoma is a tumour of the sperm cell of testes and dygerminoma is a tumour of the ovaries
what is a choriocarcinoma?
malignant tumour of the placenta
what is unique about teratomas?
they can differentiate into different tissue types and therefore can form hair and teeth in them
what is a paediatric tumour?
it is a blastoma
what do embryonal tumours look like?
they are small round blue cells - very similar in similar locations and therefore have to do genetic testing as cannot just identify through morphology
what are common embryonal tumours?
nephro, hepato, neuro, retinoblastomas
what do tumours form in embryos?
rosettes
where do medullobastomas originate?
the brainstem
how can retinoblastomas be identified?
by taking a photo of the child’s eye
what are three types of haematological malignancy?
leukaemia, lymphoma and myeloma
what is leukaemia?
it is a malignant growth from the marrow or the bone - overgrowth of a certain type of red blood cell
What is a distinguishing presentation of a haematological malignancy?
pepper pot skull in myeloma
what is a myeloma?
tumour of the plasma cells - generally not solid tumours
what is lymphoma?
there are many subtypes but is of the nodes or other solid tissues - overgrowth of the lymphocytes within lymph nodes
what happens to hodgkins and non hodgkins lymphoma?
they split into t and b cells
what is a presentation of lymphoma?
abnormally enlarged lymph nodes - need to biopsy
what are symptoms of haematological malignancies related to?
the fact that the body produces ABs
what is a hamartoma?
it is a non-neoplastic overgrowth of tissue that has a mixture of tissues of different origins. The tissue types are disorganised and can compress things and cause problems. They are benign tumour like lesions that are indigenous to a site but are a disorganised mass such as bronchial epithelium and cartilage in a lung hamartoma
what is a cyst?
it is a fluid filled space that is always lined by epithelium. It can be malignant or benign so can become invasive and neoplastic.
how is a compound tumour named?
it used the prefixes of all tissue types such as angiolipoma is a blood vessel and adipose tissue benign tumour.
how would a malignant epithelial and stromal tumour be named?
malignant epithelial is carcinoma
malignant stromal is sarcoma
therefore is a carcinosarcoma
what is a primary tumour?
when the tumour is at the site of origin
what is a secondary tumour?
when the primary tumour has turned metastatic and has spread to another site via lymph, blood or body cavities
how can you identify where it has originated if poorly differentiated?
biopsy, immunohistochemistry, examination and imaging
what is immunohistochemistry?
it is staining cells to see which proteins are expressed and therefore identifying the origin
