Gen Path - Intro to Cancer

Question 1

Cancer naming (Prefixes): If the cells of origin are:
- adipocytes
- fibrocytes
- chrondrocytes
- smooth muscle cells
- straited muscle cells
- bone

Question 2

Cancer naming (Suffixes): If the cells of origin are:

• glandular tissue (benign)
• glandular tissue (malignant)
• epithelial tissue (benign)
• epithelial tissue (malig)
• connective tissue (benign)
• connective tissue (malig)

Question 3

Note:
Malignant cancers that still end w an -oma (Exceptions to the naming!) → Hack: these are tumours that come from SPECIAL CELLS of origin (v specific cells like hematopoietic SCs, glial cells, etc)

(eg. lymphOMA, leukemia, melanoma, gliOMA, etc…)

Question 4

Describe the STAGING of cancer.

(i) definition
(ii) how to stage?
(iii) principles

Answer 4

Staging: TNM
→ assessing the DEGREE OF SPREAD of cancer
→ Tumour in pri site (invasion)? N (no. of regional lymph node metastases/affected)? Metastasis to distant site?
(note: T staging: size of tumour- more for solid organs; depth of tumour: more for luminal organs)
→ higher TNM parameters = larger spread = higher stage

Question 5

Describe the GRADING of cancer.

(i) definition
(ii) how to stage?
(iii) principles

Answer 5

Grading: Histologically
→ assessing DEGREE OF DIFFERENTIATION = how much it resembles/ doesn’t resemble normal cells/tissues it was derived from (tissue of origin) and THUS the DEGREE OF MALIGNANCY (grading = histo = DoM)
→ parameters used include: architecture, cell morphology and mitotic activity
Well differentiated = low grade cancers

Question 6

Describe tumour cells (in general).

Hint: on nuclei + on cell

Answer 6

(think of pic drawn!)

On nuclei:
- hyperchromatism
- prominent nucleoli
- enlarged nucleus
- high N/C ratio (normal is 1:4)

On cell:
- pleomorphic cells
- high mitotic activity
- necrosis (may be present)

Question 7

Outline the process of metastasis.

Answer 7

(Note: metastasis is the spread of cancer to distant sites!!)
Process:
1. Tumor cells loosens itself by inactivating E-cadherin function
2. Gain mobility via Epithelial Mesenchymal Transition (EMT)
3. Secretion of metalloproteinases, breaches underlying basement membrane
4. Cancer cells traverse interstitial tissue, penetrates vascular basement membrane
5. Either / Or :
- Invades pulmonary veins (diapedesis) -> LA -> LV -> Aorta -> carotid arteries -> cross BBB -> reaches the left lobe of the brain, forming micrometastases
- Travel to distal site (as single tumor cell or emboli), extravasate, penetration of basement membrane, angiogenesis, growth of micrometastases into new tumour (most inefficient step)

Question 8

Name the methods of metastasis.

Answer 8

Transcoelemic (“Seeding in body cavities”)
Blood
Lymphatic
etc…

Question 9

Where are the common sites of metastasis.

Answer 9

1. Lungs
2. Brain
3. Bone
4. Lymph Node

Question 10

Fill:

Tumour markers: (a few popz ones)

Calcitonin -
Alpha fetoprotein (AFP) -
Prostate Specific Ag (PSA) -
CA-125 -
CA-19-9 -
CA-15-3 -

Answer 10

Tumour markers: (a few popz ones)
Calcitonin - medullary cancer of the thyroid
Alpha fetoprotein (AFP) - hepatocellular carcinoma (HCC)
Prostate Specific Ag (PSA) - Prostate cancer
CA-125 - OVARIAN cancer
CA-19-9 - colon cancer, pancreatic cancer
CA-15-3 - breast cancer

Question 11

Define Paraneoplastic Syndrome.

Answer 11

Def: Symptom complexes in cancer patient NOT ATTRIBUTABLE to:
(i) local or distant spread of the tumour or
(ii) hormonal effects indigenous to the tissue from which the tumour arose

Question 12

Give examples of some paraneoplastic syndromes of:
1. Small cell lung cancer
2. Lung cancer (in general)
3. Pancreatic cancer

Answer 12

1.
- cushing’s syndrome
- SIADH

2. • (^)
   • Acanthosis nigricans
   • Dermatomyositis
   • Venous thrombosis
3. • Cushing’s syndrome
   • Venous thrombosis