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Question 7#

Which of the following is the CORRECT sequence of steps in a classical haematological metastatic process?

A. Growth, Extravasation & Migration, Arrest, Survival, Intravasation
B. Extravasation & Migration, Arrest, Survival, Intravasation, Growth
C. Intravasation, Arrest, Extravasation & Migration, Survival, Growth
D. Intravasation, Arrest, Survival, Extravasation & Migration, Growth
E. Extravasation & Migration, Arrest, Growth, Survival, Intravasation

Correct Answer is C

Comment:

Answer C

The steps of the metastatic process are:

  1. Intravasation – The movement of cells into the blood stream.
  2. Arrest – Cancer cells are larger than most capillaries and hence lodge themselves within the capillaries resulting in arrest.
  3. Extravasation & Migration – Some cells die at the arrest stage but others will pass out of the endothelium into tissue due to the action of cell adhesion molecules, extracellular matrix, growth factors and chemokines.
  4. Survival & Growth – The survival and growth of tumour cells once they are within a particular organ is entirely due to the environment within the organ itself and to the particular tumour cell. Cell-cell, cell-matrix, and growth factor interactions are required for malignant cells to survive and for tumour cells to grow and produce metastatic lesions.