L8-10 Neoplasia Flashcards
What are the differences between benign and malignant neoplasm in terms of gross features? (3)
- Capsule / No capsule
- Compressing / destruction of surrounding tissues
- No necrosis / necrosis + haemorrhage
What are the differences between benign and malignant neoplasm in terms of microscopic features?
- Highly / poorly differentiated cells
- Normal / bizarre mitotic activity
- No metastasis / metastasis
- Normal DNA / increased DNA content
What are the characteristics of malignant cell nuclei? (5)
- Hyperchromatic
- High nuclear to cytoplasmic ratio
- Irregular nuclear outline
- Coarse clumped chromatin
- Enlarged nucleoli
What are the 6 hallmarks of cancer?
- Evading apoptosis
- Self-sufficiency in growth signals
- Insensitivity to anti-growth signals
- Tissue invasion + metastasis
- Limitless replicative potential
- Sustained angiogenesis
What is an example of tumour suppressor gene?
p53
What are the 3 environmental triggers of genetic changes?
- Chemical carcinogens (smoking, alcohol, betel nut chewing)
- Radiation (X-ray, UV light)
- Viruses (HPV, EBV)
How does tumours evade body’s immune system?
Tumours exploit PD-1 dependent immune suppression –> limits the activity of T-cell
What is grading in neoplasia and how is it determined?
The grade of a malignant neoplasm refers to its degree of malignancy (according to the degree of differentiation). It is determined histologically.
What are the 6 routes of cancer dissemination
- Local infiltration (Rectum –> bladder)
- Spread though body cavities (colon –> ovary)
- Lymphatic spread (H&N –> cervical lymph node)
- Hematogenous spread (GI –> liver via portal vein)
- Perineural infiltration
- Pagetoid spread (epithelial lining)
What does T,N,M stand for in cancer staging?
- T: cancer at primary site
- N: regional lymph node spread
- M: metastasis to distant organs
What is paraneoplastic syndromes?
It is symptom complexes in cancer patients not attributable to local or distant spread of the tumour or hormonal effects indigenous to the tissue from which the tumour arose (basically the clinical symptoms don’t match the site of tumour)
Examples of paraneoplastic syndromes
- Cushing’s syndrome due to increased ACTH, but the underlying cancer is small cell carcinoma of lung / pancreatic carcinoma
- Inappropriate antidiuretic hormone secretion due to increased secretion of ADH, but the underlying cancer is small cell carcinoma of lung / intracranial neoplasms
- Hypercalcemia due to increased secretion of parathyroid hormone, but the underlying cancer is squamous cell carcinoma of lung, breast carcinoma, renal carcinoma, etc
Moral of the story: lung cancer can have weird weird unpredictable symptoms lol
What is the tumour marker for liver cell cancer?
alpha Fetoprotein
What is an example of a malignant tumour that commonly has differentiated cells?
Endocrine tumours
What are the 3 sampling techniques for cancer detection?
- Excision / biopsy
- Cytologic smears (PAP smear)
- Fine needle aspiration
All of those above is followed by cytologic examination under a microscope