Topic 3 - Neoplasms

Question 1

Define carcinogen.

Answer 1

The agent known or suspected to cause the formation of

tumour

Question 2

Define carcinogenesis.

Answer 2

The process which results in the transformation of normal cells to neoplastic cells by causing permanent genetic alterations or mutations.

Question 3

List some group 1 carcinogens

Answer 3

Smoking, exposure to solar radiation, alcoholic beverages and processed meats.

Question 4

What is a neoplasm?

Answer 4

an abnormal mass of tissue that forms when cells grow and divide more than they should or do not die when they should
also known as tumours

Question 5

What is the structure of a neoplasm?

Answer 5

Consists of 
(1) Neoplastic cells that are reproduced to a certain extent and (2) Stroma - a connective tissue framework that supports the growth of neoplastic cells by providing mechanical and nutritional support to the tumour. It contains blood vessels to supply blood to the tumour.

Question 6

Differentiate the characteristics of a benign and malignant neoplasm in terms of growth rate, structure/histology, local invasion and metastasis.

Answer 6

Benign - slowly over a period of years, well differentiated from parent cells, remains localized to their site of origin as tumour cells are usually cohesive and well-demarcated masses and do not metastasize

Malignant - rapid erratic pace, can range from well differentiated to undifferentiated cells (usually undifferentiated), tumour cells will invade/infiltrate surrounding tissue and most likely will metastasize

Question 7

Define invasion

Answer 7

a term used to describe the infiltration and

destruction of surrounding tissue by the malignant tumours.

Question 8

Define metastasis.

Answer 8

the process whereby malignant tumors spread
from their site of origin (primary tumors) to form distant
secondary tumors.
(The more aggressive the primary tumour, the more rapidly it will grow.For larger primary tumour, it is more likelihood that it will metastasize.)

Question 9

3 types of metastasis?

Answer 9

Haematogenous (through the bloodstream), lymphatic (through lymphatics to regional lymph nodes) and transcoelomic (invasion of body cavity)