Using the pathologist Flashcards
Define neoplasia 3
- uncontrolled cell proliferation
- proliferation continues in absence of inciting cause
- neoplastic cells originate from single cell which has lost ability to control its division
What is tumour classification based on?
clinical and pathological features
What are gross features of benign tumours
growth by expansion low to moderate growth rate tumour well demarcated (compresses surrounding tissue) smooth in gross outline surrounding CT capsule freely mobile on palpation homogenous cut surface (cystic in glandular tissue) little haemorrhage or necrosis surgical removal often easy no recurrence if completely excised no metastasis
What are microscopic features of benign tumours?
very similar to tissue of origin
well organised
benign endocrine tumours can be functional
surrounding CT capsule - tumour doesn’t broach this
few or no mitoses
generally no haemorrhage or necrosis
Gross features - malignant tumours
growth by invasion
not encapsulated
not usually mobile on palpation
complete removal often difficult
often recurs after excision
often ulcerate if on skin or mucosal surface
secondary changes - internal necrosis and haemorrhage
can metastasise to local LNs and lungs (often)
Microscopic features - malignant tumours
pleomorphism anisokaryosis increased nuclear: cytoplasmic ratio prominent nucleoli normal/abnormall mitoses loss of cohesiveness and structure syncytia secondary changes - necrosis, fibrosis, inflammation usually not encapsulated
Define anisokaryosis
variable size and shape of nucleoli
Define pleomorphism
variable cell size and shape
Define papilloma
benign, surface epithelia
Define adenoma
Benign tumour, glandular epithelia
Define thyroid adenoma
glandular epithelia (benign) tumour prefixed by the tissue of origin
Define carcinoma
malignant, epithelial origin
Define adenocarcinoma
malignant tumour of glandular epithelia
Is a tumour ending in -oma benign or malignant?
Benign (except granuloma - chronic inflammation). Tumours with the ending -sarcoma are malignant
Define lymphoma
tumours of lymphoid system
usually malignant
Define melanoma
Tumour of melanocytes
some benign, other malignant (malignant melanomas)