Investigating Disseminated Malignancy

Question 1

List the possible routes of metastatic spread.

Answer 1

Seeding into body cavities;
Neuronal;
Lymphatic;
Vascular (most common to lung, liver, brain, bone)

Question 2

List some common presentations of metastatic malignancies.

Answer 2

Systemic presentations include fatigue, weight loss, rash, night sweats, and bone pain.
Other presentations include headaches, seizures, cough, haemoptysis, dyspnoea, lymphadenopathy, hepatomegaly, jaundice, factures.

Question 3

Why is it important to investigate a disseminated malignancy?

Answer 3

To diagnose the primary tumour type, which is important for the correct treatment, adequate prognosis, genetic counselling, and to maintain accurate cancer statistics.

Question 4

What is the term for a malignant neoplasm of epithelial origin? How do these tend to metastasise?

Answer 4

Carinoma, spread by lymphatics, hematogenous, seeding.

Question 5

What is the term for a malignant neoplasm of mesenchymal origin? How do these tend to metastasise?

Answer 5

Sarcoma, spread by hematogenous, most commonly to lung.

Question 6

What is the term for a malignant neoplasm of melanocyte origin? How do these tend to metastasise?

Answer 6

Melanoma, spread by lymphatics, hematogenous.

Question 7

List some common sites for squamous cell carcinoma.

Answer 7

oral cavity, oesophagus, lung, cervix, skin.

Question 8

List some common sites for adenocarcinoma.

Answer 8

GI tract, lung, breast, pancreas, gall bladder, uterus, ovaries.

Question 9

List some common sites for urothelial cell carcinoma.

Answer 9

renal pelvis, ureters, urinary bladder, urethra.

Question 10

List some common types of sarcomas.

Answer 10

Muscle: leiomyosarcoma.
Bone: osteosarcoma.
Adipose tissue: liposarcoma.
Cartilage: chondrosarcoma.

Question 11

Which immunohistochemical stain is used to detect a tumour of epithelial origin?

Answer 11

Cytokeratin.
AE1/AE3 will stain positive in epithelial cells of all origins.
There are many different subtypes, commonly used is CK7 and CK20, as some epithelial origins express only CK7 (lung, breast, ovary, endometrium), some express only CK20 (colorectal), some express both CK7 and CK20 (pancreaticobiliary, urothelial), and some neither (prostate, liver), to further identify origin.

Question 12

Which immunohistochemical stain is used to detect a tumour of mesenchymal origin?

Answer 12

vimentin, specifically desmin for a leiomyosarcoma.

Question 13

Which immunohistochemical stain is used to detect a tumour of lymphoid origin?

Answer 13

leucocyte common antigen (LCA).

Question 14

Which immunohistochemical stain is used to detect a tumour of melanocyte origin?

Answer 14

S100.

Question 15

Which epithelial origins in cytokeratin staining are CK7 positive and CK20 positive?

Answer 15

urothelial, pancreaticobilliary.

Question 16

Which epithelial origins in cytokeratin staining are CK7 positive and CK20 negative?

Answer 16

lung, breast, ovary, endometrial.

Question 17

Which epithelial origins in cytokeratin staining are CK7 negative and CK20 positive?

Answer 17

colorectal.

Question 18

Which epithelial origins in cytokeratin staining are CK7 negative and CK20 negative?

Answer 18

renal cell, prostate, hepatocellular.

Question 19

Define neoplasm.

Answer 19

An abnormal mass of tissue, growth of which exceeds and is uncoordinated with the normal surrounding tissues, and which persists in the same excessive manner after the cessation of the stimuli which evoked it.