Question

Explain metastasis. Why is it fatal?

Answer 1

Hint: The disease which is caused by the abnormal and uncontrollable division of cells, which could destroy the body tissues, is known as cancer. The alterations in DNA (deoxyribo nucleic acid) are the main cause for cancer.

Complete answer:
The pathogenic agent spread from primary or initial site to a secondary or different site, present in the host body is known as metastasis. This term is used in reference to cancerous tumors. And the newly pathogenic sites are named as metastases. The common locations of metastasis are brain, bone, lung, liver and lymph nodes.

Metastatic cancer is fatal because it has the ability to spread inside the body. The cancer could infect the nearby tissues by spreading. The cells could spread regionally also, such as, organs, tissues, and lymph nodes. When this type of spread happens, it is also termed as stage four cancer, done by metastasis.

The metastasis happens in a series of events, such as growth and invasion of cancer cells to nearby tissues, movement of cells towards the lymph node, growth in tissues forming tumors, growth of new blood vessels to supplement their nutrient growth.

Note: It is being observed under the microscope that the metastatic cells have similar features as that of primary cells, and not the type of cancer cells that conventionally should be found in that region. For example- when the lung cancer spreads in the breast by metastasis, then it is not named as breast cancer. Scientifically, it is lung cancer, at stage four and the treatment for the same is given.