Tumours: behaviour and spread

Question 1

What do benign tumours look like in solid organs

Answer 1

Spherical mass because they grow evenly in all directions

Question 2

How do benign tumours on epithelial surfaces grow

Answer 2

IN direction of least resistance (they are called papillomas because of their papillary shape)

Question 3

What do malignant tumours look like

Answer 3

Irregular in outline and have indistinct edges because they expand and infiltrate adjacent tissue

Question 4

How do we tell if a tumour is benign or malignant in its early stages

Answer 4

perform a biopsy to assess the cytological characteristic of the tumour cells

Question 5

What are the cytological characteristics of malignancy

Answer 5

• Pleomorphism- cellular/nuclear
• High nucleus to cytoplasm ratio
• Nuclear hyperchromatism
• High mitotic count
• Abnormal mitoses

Question 6

what is cellular pleomorphism

Answer 6

Variation in size and shape of cells in tumour

Question 7

what is nuclear pleomorphism

Answer 7

Variation in shape and size of nuclei in tumour cells

Question 8

What is nuclear hyperchromatism

Answer 8

Very dark staining nuclei due to increased nuclear DNA

Question 9

What is high mitotic count

Answer 9

Increased numbers of cells in mitosis, including abnormal mitotic forms

Question 10

How can you tell if there is abnormal mitosis

Answer 10

Nucleus is in a Y shape

Question 11

What is dysplasia

Answer 11

Abnormal cell structure

Question 12

Does dysplasia in tumour cells always mean invasive behaviour ?

Answer 12

Usually, but not always

Question 13

What is carcinoma-in-situ or intra-epithelial neoplasia

Answer 13

Dysplasia in an epithelium that does not show invasion across the epithelial basement membrane

Question 14

What happens to dysplasia?

Answer 14

Sometimes it disappears (regresses) but more often, it turns into invasive malignancy

Question 15

How does a malignant tumour spread lymphatically

Answer 15

It invades into the lumen of a lymphatic vessel and bits can break off and pass to the lymph nodes draining the area

Question 16

What happens to a tumour when in the lymph node

Answer 16

Gets trapped in the sub scapular sinus and there, the tumour cells proliferate until the whole node is replaced by tumour

Question 17

How do tumours spread in blood stream

Answer 17

Invades the wall of a small vessel, clumps of tumour cells break off and pass in the circulation until they meet a vessel too small to let It pass and then they grow to produce a distant metastasis

Question 18

Where are secondary deposits in bone usually from

Answer 18

Breast
Bronchus/lung
Kidney
Thyroid 
Prostate

Question 19

How can benign tumours cause illness and death by

Answer 19

Bleeding
Pressure on adjacent vital structures
Obstruction
Hormone secretion (eg pituitary adenoma)
Conversion to a malignant tumour