9 metastasis Flashcards
(66 cards)
What is metastasis?
the spread of a tumour from the primary organ to distant sites in the body, making cancer more difficult to treat and responsible for most cancer-related deaths.
Why is metastatic disease difficult to treat?
It involves multiple steps, heterogeneity among tumour cells, and resistance to therapy, requiring more targeted treatments.
What are the primary routes of metastatic spread?
Blood vessels (haematogenous), lymphatic system, and body cavity movement (peritoneal or pleural spread).
How does lung metastasis cause mortality?
It impairs respiratory function, leading to breathing difficulties and organ failure.
What are the effects of liver metastases?
Liver metastases can cause bile duct obstruction, liver failure, and altered metabolism.
Why is pancreatic metastasis dangerous?
It disrupts insulin production, leading to diabetes-like symptoms, and affects digestive enzyme secretion.
How does bone and bone marrow metastasis lead to complications?
It disrupts haematopoiesis, leading to anaemia, infections, and bone marrow failure.
What are the consequences of brain metastases?
They can cause loss of neurological function, seizures, and brain herniation.
How does heart metastasis impact the body?
It can cause cardiac failure, arrhythmias, and vasospasm, potentially leading to sudden death.
What is the effect of metastases in the kidneys?
They cause kidney dysfunction, failure, and an increased risk of sepsis due to ureteric obstruction.
How do digestive tract metastases contribute to mortality?
They impair digestion, nutrient absorption, and can cause perforation, leading to severe infections.
What are the main steps of metastasis?
Transformation
→ Angiogenesis
→ Mobility & Invasion
→ Embolism & Circulation
→ Arrest in Capillary Beds
→ Adherence
→ Extravasation
→ Response to Microenvironment
→ Tumour Cell Proliferation
→ Metastases Formation
→ Secondary Metastases.
What happens during the transformation step?
Normal cells acquire mutations that enable uncontrolled growth and invasion of surrounding tissues.
Why is angiogenesis important in metastasis?
Tumours need blood vessels to supply oxygen and nutrients for growth and allow entry into circulation.
What enables cancer cells to become mobile and invade tissues?
Changes in adhesion molecules, cytoskeletal reorganisation, and increased protease activity help tumour cells move and invade.
What occurs during embolism and circulation?
Cancer cells enter the bloodstream or lymphatic system, often protected by platelets, to avoid immune destruction.
How do tumour cells arrest in capillary beds?
They adhere to endothelial cells using adhesion molecules and become trapped in narrow capillaries.
What is extravasation in metastasis?
The process where cancer cells exit the bloodstream and invade organ parenchyma to establish a secondary tumour.
Why is the tumour microenvironment important for metastasis?
It provides essential signals, nutrients, and growth factors that allow metastatic cells to survive and proliferate.
What is metastasis of metastases?
Secondary tumours can also spread to new sites, forming additional metastatic tumours.
How does colorectal cancer metastasise?
It spreads through lymphatic (to lymph nodes), transcoelomic (to peritoneum), and haematogenous (to liver) routes.
Why is the liver a common site for blood-borne metastases?
It acts as a first-pass organ for venous blood, filtering tumour cells from circulation.
What are common secondary sites for breast cancer metastases?
Bone, liver, lungs, and lymph nodes (especially in the armpit).
What is the “Seed and Soil” hypothesis?
It suggests tumour cells (seeds) prefer specific environments (soil) that provide favourable conditions for growth.