Sesh 8.1 Neoplasia 1

Question 1

What is a neoplasm?

Answer 1

Abnormal proliferation of cells that persists after stimulus is removed

Question 2

What is a malignant neoplasm?

Answer 2

Neoplasm that invades surrounding tissue with potential to spread to distant sites

Question 3

What is a metastasis?

Answer 3

A malignant neoplasm that has spread to a non-contiguous site

Question 4

What is dysplasia?

Answer 4

Reversible pre-neoplastic alteration. Cells show disordered tissue architecture.

Question 5

How do benign and malignant neoplasms differ?

Answer 5

Benign neoplasms are confined to their site of origin, and are well differentiated.
Malignant neoplasms invade surrounding tissue, have potential to metastasis, impose larger tumour burden, and may be poorly or well differentiated.

Question 6

What are histological signs of poor differentiation?

Answer 6

• Increased nuclear to cytoplasmic ratio
• Hyperchromasia of nucleus
• More mitotic figures
• Increased nuclear size
• Pleomorphism

Question 7

A high grade tumour indicates ______ differentiation.

Answer 7

Poor

Question 8

What is carcinoma in situ?

Answer 8

A neoplasm that has not invaded the basement membrane.

Question 9

Briefly, how do neoplasms form?

Answer 9

An initiator causes a mutation within a gene by chance. Then need exposure to promoters for a long time to lead to neoplasm formation. Finally need progression- accumulation of further mutations.

Question 10

What is the 2 hit hypothesis?

Answer 10

Neoplasm formation requires ‘2 hits’ in order to inactivate both alleles of tumour suppressor genes and allow uncontrolled cell proliferation.