Disorders of Growth Flashcards
NEOPLASM
“A NEOPLASM is an abnormal mass of tissue, the growth of which exceeds and is unco-ordinated with that of normal tissues, and which persists in the same excessive manner after cessation of the stimuli which evoked the change.”
- Sir Rupert Willis, 1960
NEOPLASIA
NEOPLASIA is the process by which a neoplasm is formed.
TUMOUR
TUMOUR literally means swelling, but conventionally is used as a synonym for neoplasm
BEHAVIOUR of Tumours
A benign tumour grows by expansion, displacing adjacent tissue
A malignant tumour grows by infiltration of local tissues, and spreads to other parts of the body
Primary tumour
original malignant tumour
Secondary tumours
“offspring” of a primary malignant tumour
SPREAD OF MALIGNANT TUMOURS
Local - direct invasion
Distant – metastasis
ROUTES OF METASTASIS
lymphatics blood transcoelomic along epithelial-lined spaces within epithelium
METASTASIS VIA LYMPHATICS
tumour may directly invade lymphatics
tumour emboli filtered out, then grow, in lymph nodes
typical of epithelial malignancy
METASTASIS VIA BLOOD
tumour may invade blood vessels
emboli filtered out by capillary beds, eg liver, lung
typical of stromal malignancy and later stages of epithelial malignancy
METASTASIS VIA TRANSCOELOMIC SPREAD
peritoneal, pleural
METASTASIS VIA EPITHELIAL-LINED SPACES
bronchiolo-alveolar carcinoma of lung
METASTASIS WITHIN EPITHELIUM
Paget’s disease of nipple, vulva and anus
PARTICULAR SITES OF METASTASES - LIVER
liver: GIT carcinomas, GUS, bronchus, breast
PARTICULAR SITES OF METASTASES - LUNG
lungs: sarcoma; carcinoma of thyroid, breast, kidney, bronchus, etc.
PARTICULAR SITES OF METASTASES - BONE
bone: carcinoma of breast, thyroid, bronchus, prostate, uterus
PARTICULAR SITES OF METASTASES - BRAIN
brain: carcinoma of bronchus