Neoplasia 2: Spread of Malignant tumors

Question 1

Explain how Malignant tumors invades ECM

Answer 1

1. Tumor cell loses cell cohesion and detaches from rest of tissue by loss of Cadherin
2. Attachement of tumor cell to laminin of basement membrane & fibronectin of ECM
3. Degredation of ECM by Typer 4 collagenase & Cathepsin D
4. Migration of tumor cell by pseudopodia using autocrine mobility factors
5. Acquirement of negative charges on its surface to repel other cells —> loss of contact (cell to cell) inhibition

Question 2

Enzymes used by malignant tumors to degrade ECM, & their function

Answer 2

• Type 4 collagenase: lysis of basement membrane
• Cathepsin D: lysis of interstitium

Question 3

Explain how tumor gains mobility & pseudopodia

Answer 3

by tumor- derived cytokine= Autocrine motility factors

Question 4

Order of BV from most penetrable to least penetrable by tumor

Answer 4

1. Lymphatics
2. Capillaries
3. Venules
4. (rarely) Arterioles

Question 5

Explain who lymphatics are the most penetrable by tumors

Answer 5

due to lack of basement membrane

Question 6

Describe fate of tumor emboli

Answer 6

• Most tumors emboli are destroyed by immune system
• Some adhere to platelets, protecting themselves from immune system
• They get impacted into small vessels, then adhere to endothelium, then cross the basement membrane, to reach & settle in a new site (homing)

Question 7

Define organ tropism

Answer 7

Expression of adhesion molecules on the tumor cell whose ligands are expressed by endothelial & the metastic site, or chemokine receptors on the tumor cell

Question 8

Examples of organ tropism

Answer 8

• Prostatic carcinoma spreads to bone
• bronchogenic carcinoma spreads to adrenal glands or brain
• Neuroblastoma to liver & bones

Question 9

Routes of spread of tumor is divided into ____

Answer 9

• Direct (local) spread
• Distal spread= Metastis

Question 10

define direct/local spread

Answer 10

progressive infiltration, invasion & destruction of surrounding tissue

Question 11

Which type of tissue delays local spread of tumor

Answer 11

• Bone
• Cartilage
• elastic tissue
• fibrous tissue

Question 12

Metastis is divded into ___

Answer 12

• Lymphatic spread
• Blood (hematogenous) spread
• Transcoelomic Spread
• Transluminal Spread

Question 13

Lymphatic spread is more common in what type of Cancer

Answer 13

Carcinoma (than sarcoma)

Question 14

gross pathology of tumor emboli of Lymph nodes

Answer 14

• Enlarged
• hard
• fixed
• painless

Question 15

explain how lymphatic spread reaches hematogenous spread

Answer 15

tumor spreads in lymph to reach main lymphatic ducts (thoracic duct) —> Venous circulation—> blood

Question 16

Definition of Lymphatic permeation

Answer 16

Solid columns inside lymphatics causing obstruction (no drainage) —> Lymphatic edema

Question 17

which cancer shows lymphatic permeation (lymphatic edema)

Answer 17

Breast cancer

Question 18

Clinical diagnosis of enlarged LN near primary neoplasm

Answer 18

• Doesn’t mean cancer has infiltrated the node
• may be due to necrotic products of the neoplasm & tumor antigens stimulates immunologic response in the node (Lymphadenitis)/ sinus histocytosis (macrophage accumulation at sinuses)

Question 19

Define sentient lymph node

Answer 19

First regional lymph node receiving lymph from site of primary tumor

Question 20

Explain how sentient LN is traced and studied

Answer 20

• Inject blue dye/ radiolabeled tracers near the site of tumor
• remove LN & study (biopsy) using frozen section

Question 21

Most common organs affected by Hematogenous spread

Answer 21

• Liver
• Brain
• Lung
• Bone

LBLB

Question 22

Explain how lung metastases come from blood spread

Answer 22

Emboli moves in systemic veins from organ to right side of the heart via Vena Cava —> Pulmonary arteries —> Lung Metastase

Question 23

how does primary/metastic lung cancer spread to other organs

Answer 23

Emboli spreads through pulmonary veins to left side of the heart —> Aorta —> systemic arterial circulation

Question 24

Emboli reach portal veins from GIT may cause Metastase in ___

Answer 24

Liver

Question 25

Emboli that reaches hepatic vein may cause metastase in ___

Answer 25

Lungs (drains in IVC –> rt side heart –> pulmonary artery)

Question 26

verterbaral metastase is common from what types of Carcinomas

Answer 26

• Prostate
• Thyroid

Question 27

in what case is bone metastase osteosclerotic/osteoplastic (builds bone) instead of osteolytic (common), and why ?

Answer 27

prostate cancer

It secretes phosphate

Question 28

gross picture of blood metastase

Answer 28

scateered rounded nodules with central umblication (depression) of variable sizes

Question 29

Microscopic picture of blood metastase

Answer 29

resmbles primary tumor of ewhich they are derived

Question 30

Define transcoelomic metastase

Answer 30

primary tumor from an organ surrounded by serous membrane to be implanted on serosal surface of other organ

Question 31

macroscopic picture of transperitoneal metastase

Answer 31

peritoneal/ omental nodules with hemorrhagic ascites

Question 32

Explain Kurkenberg tumors

Answer 32

Carcinoma of stomach or colon causes Bilateral ovarian metastase

Question 33

cause of kurkenberg tumors is now believed to be ____

Answer 33

• retrograde lymphatic flow
• Blood spread

Question 34

sites of CSF metastase

Answer 34

• Ventricles
• base of skull
• spinal cords

Question 35

Example of translumenal spread

Answer 35

transitional carcinoma of renal pelvis is implanted in mucosa of urinary bladder