The term “tumour progression” means -
1.Spread of cancer to distant site
2.Rate of growth of tumour
3.Ability of cancer cells to resemble their normal counterpart
4.Sequential appearance of feature of increasing malignancy
Explanation
Malignant neoplasm has several characterstics that are acquired in a stepwise fashion, a phenomenon called tumor progression.
The natural history of most malignant tumors has following four phages -
Malignant change in the target stem cell → Due to genetic or/and environmental factors stem cell is transformed into tumor cell a process is known as transformation and proliferation.
Growth and proliferation of transformed cell
Local invasion
Metastasis