cancer 2 Flashcards
(18 cards)
- Define metastasis and its clinical significance.
Model Answer:
Metastasis refers to the spread of malignant tumour cells from the primary site to distant tissues forming secondary implants. It is a hallmark of malignancy and the major cause of cancer-related mortality. Metastases are discontinuous with the primary tumour and confirm the tumour’s malignant nature.
- Describe the three main pathways of metastasis.
Model Answer:
Lymphatic spread: Typical of carcinomas, spreads to regional lymph nodes via lymphatic vessels.
Haematogenous spread: Common in sarcomas; tumour cells spread via blood vessels to organs like lungs, liver, brain, and bones.
Transcoelomic spread: Tumour cells spread across body cavities (e.g., peritoneal, pleural), as seen in ovarian, appendiceal, and lung cancers.
- Outline the steps of the invasion-metastasis cascade.
Model Answer:
Local invasion of surrounding tissue
Intravasation into blood or lymph vessels
Survival in the circulation
Extravasation at a distant site
Formation of micrometastasis
Growth into macroscopic secondary tumour
- What is the clonal theory of metastasis?
Model Answer:
The clonal theory suggests that tumours evolve through a selection of increasingly malignant subclones. These subclones acquire genetic and phenotypic changes that enhance their capacity to invade, metastasize, and resist treatment.
- List key behavioural and biomedical risk factors for cancer.
Model Answer:
Behavioural: Smoking, alcohol, poor diet, physical inactivity, sun exposure
Biomedical: Obesity, diabetes
These factors contribute significantly to the cancer burden measured by DALYs.
- Which of the following cancers commonly spreads via transcoelomic seeding?
A. Breast cancer
B. Lung carcinoma
C. Appendiceal mucinous neoplasm
D. Renal cell carcinoma
Answer: C. Appendiceal mucinous neoplasm
- Which pathway of metastasis is typical for sarcomas?
A. Lymphatic
B. Haematogenous
C. Transcoelomic
D. Perineural
Answer: B. Haematogenous
- What is the most significant modifiable risk factor for cancer in Australia?
A. Alcohol
B. Obesity
C. Tobacco
D. Physical inactivity
Answer: C. Tobacco
- Which of the following is considered a pre-neoplastic condition?
A. Leiomyoma
B. Barrett’s oesophagus
C. Lipoma
D. Papilloma
Answer: B. Barrett’s oesophagus
- A Krukenberg tumour is best described as:
A. Primary ovarian adenocarcinoma
B. Metastatic carcinoma to the ovary from the stomach
C. Benign mucinous ovarian cyst
D. Primary gastrointestinal lymphoma
Answer: B. Metastatic carcinoma to the ovary from the stomach
Q: What confirms a tumour as malignant?
A: The presence of metastases.
Q: Which cancers are associated with lymphatic spread?
A: Carcinomas, like breast and lung cancer.
Q: What are the common sites for metastases?
A: Liver, lungs, bones, and brain (L2BB mnemonic).
Q: What enzymes help tumour cells degrade the ECM during metastasis?
A: Matrix metalloproteinases (MMPs), cathepsin D, urokinase plasminogen activator.
Q: Define pseudomyxoma peritonei.
A: A condition where mucinous tumour fills the peritoneal cavity, often from appendiceal neoplasms.
Q: How does obesity contribute to cancer risk?
A: Through increased inflammation, which promotes carcinogenesis.
Q: What is a DALY?
A: Disability-adjusted life year; a measure combining years lost to early death and years lived with disability.
Q: What characterizes the clonal evolution of tumours?
A: The development of genetically diverse and more aggressive subclones.
