1. What is the primary mechanism by which cancer cells achieve

metastasis?

 A. Angiogenesis

 B. Apoptosis

 C. Epithelial-mesenchymal transition (EMT)

 D. Mitosis

 Answer: C. Epithelial-mesenchymal transition (EMT) is a process by

which cancer cells gain migratory and invasive properties, allowing them

to spread to other parts of the body.

2. Which theory suggests that metastasis occurs in a non-random pattern

based on the circulatory pathways?

 A. Paget's 'Seed and Soil' theory

 B. Ewing's theory

 C. Halsted's theory

 D. Fisher's theory

 Answer: A. Paget's 'Seed and Soil' theory posits that metastasis depends

on the interaction between specific cancer cells (the 'seed') and a favorable

microenvironment (the 'soil').

3. According to the 'mechanical' theory of metastasis, what determines the

location of secondary tumors?

 A. The genetic profile of cancer cells

 B. The anatomical structure of the vascular system

 C. The presence of certain hormones in the target tissue

 D. The metabolic rate of the target tissue

 Answer: B. The 'mechanical' theory suggests that the anatomical

structure of the vascular system determines where circulating cancer cells

will lodge and form secondary tumors.

4. What role does the lymphatic system play in metastasis according to the

'lymphatic' theory?

 A. It provides nutrients to cancer cells.

 B. It acts as a barrier to cancer cell spread.

 C. It serves as a conduit for cancer cells to disseminate.

 D. It has no role in metastasis.

 Answer: C. The 'lymphatic' theory posits that the lymphatic system