Neoplasia 2 Flashcards
Describe the differences between benign and malignant tumours
Benign:
- typically expand, compressing surrounding tissue
- well-differentiated (similar structure to tissue of origin)
- slow, progressive expansion
- no anaplasia
- little necrosis
- no invasion
- capsule
- no metastasis
Malignant:
- invade and spread (metastasise)
- poorly differentiated
- tissue of origin can be unclear
- anaplasia
- rapid growth
- frequent mitotic figures
- necrosis if poor blood supply
- local invasion
- infiltrative growth
- capsule often absent
- metastasis
What is anaplasia and atypical cells?
- poorly differentiated cells
What is Pleomorphism?
- variable appearance
What is Anisocytosis?
- varied cell size
What is Anisokaryosis?
- varied nuclear size
What is Hyperchromasia?
- dark nuclei (condensation)
What would increased nuclear to cytoplasmic ratio mean?
- increased nuclear content
What is Karyomegaly?
- giant nucleus
What are tumour giant cells?
- giant cells
Multinucleate?
- more than 1 nuclei
What is a prominent nucleoli?
- enlarged or conspicuous nucleolus
What is bizarre mitoses?
- abnormal conformation
What are all of these?
- cytological features of malignancy (learn together)
What does this show and what features can you see?
- Liposarcoma
- Anisokaryosis
- anisocytosis
- hyperchromasia
- bizarre mitoses
- tumour giant cells
- poor differentiation - may be going anaplastic
- multinucleate
- haemorrhage- rbcs outside as endothelium
What is this?
- bronchoalveolar carcinoma
- anaplasia
- increased nuclear to cytoplasmic ratio
- hyperchromasia
- bizarre mitsoses
- arrow heads - cell death, necrosis, neutrophils (inflam)
- multinucleation
What are the morphological features of malignancy?
- loss of tissue organisation - effacement and disorganisation
- invasion - destruction of adjacent tissue
- no capsule or invasion of capsule - poorly demarcated
- vascular invasion - blood and or lymphatic invasion
- metastasis - spread from site of previous tumour
- necrosis - ischaemia and inflam
- haemorrhage - damage to vessels and angiogenesis
What differences can you see between hyperplastic lymph node vs. lympoma (benign vs. malignant)
- hyperplastic lymph- large lymph nodes
- normal architecture but boundaries are still present
- lymphoma - connective tissue not present so boundaries not present
- haemorrhage due to necrosis and lack of blood supply
- uncontrolled cell growth
Is the showing a hyperplactic lymph node or lymphoma?
- hyperplastic lymph node
What is this?
- lymphoma
This is a squamous cell carcinoma- what features can you see?
- no keratin (SS ep usually produces)
- keratin pearls present
- still producing keratin- just dont care where they put it
- hyperchromasia
- bizarre mitoses
What is the hallmark of neoplasia?
- uncontrolled proliferation
- cell escapes all of its control mechanisms
- escapes apoptosis
- independent of external growth factors and regulations
What are the genetic factors contributing to carcinogenesis?
- DNA mutations
- point mutations
- deletion
- insertion
- recombination
- amplification
- gene conversion
- Epigenetic changes
- DNA methylation
- imprinting
- histone methylation
- histone acetylation
- Chromosomal alterations
- duplication
- deletion
- translocation
- inversion
What are telomeres?
- pieces of DNA at the end of chromosomes
- pieces are cut off at each cell division
How to tumour cells avoid ageing/ apoptosis?
- add more telomeres to the end of chromosomes
- reactiavte telomerase
- are then immortal to aging
How does a tumour form?
- one cell undegoes damage (initiated cell)
- transformation event - e.g. radiation
- the initiated cell enters a proliferative event
- the daughter cells will inherit the abnormalities
- evolves to a preneoplastic benign tumour after promotion
- then can progress to a malignant tumour
What is p53?
- in all cells
- detect any damage
- tells the cell to stop dividing
- and undego apoptosis if DNA damage cannot be repaired
- with no p53 - more prone to tumours
What substances does the tumour produce to communicte with the stroma?
- growth factors
- inflammatory mediators
- proteases
- tumour antigens
What is the stromal response to a tumour?
- Inflammatory cells
- stromal fibroblasts
- extracellular matrix (growth factors)
- vascular endothelium
What does this show?
- normal angiogenesis
- stable
- organised
- limited permeability
What does this show?
- tumour angiogenesis
- unstable
- disorganised
- leaky
What are the pink cells?
- pericyte
