Growth, cell death & neoplasia Flashcards
Define hypertrophy
INC in size of tissue caused by INC in size of constituent cells
Give a physiological example of hypertrophy
INC in skeletal muscle during exercise
Give a pathological example of hypertrophy
Cardiac muscle hypertrophy due to hypertension
Define hyperplasia
INC in size of tissue caused by INC in number of constituent cells
Give a physiological example of hyperplasia
Uterine cells during pregnancy (also undergo hypertrophy)
Give a pathological example of hyperplasia
Endometriosis
Benign prostatic hyperplasia
Define atrophy
DEC in size of tissue caused by DEC in number of constituent cells/DEC in their size
Give a physiological example of atrophy
Thymus atrophy during childhood
Give a pathological example of atrophy
Muscular dystrophy
Define metaplasia
Replacement of one fully differentiated tissue by another
Give a pathological example of metaplasia
Barrett’s oesophagus (normal stratified squamous epithelium –> simple columnar epithelium w/ goblet cells)
If stimulus not removed, can progress to oesophageal adenocarcinoma.
Define dysplasia
Morphological changes seen in cells in the progression to becoming cancer
What are the morphological changes seen in cells in the progression to cancer?
- Variation in size & shape
- High nuclear/ cytoplasmic ratio
- Increased mitotic figures
Give a pathological example of dysplasia
Cervix: normal glandular epithelium –[HPV infection]–> immature squamous epithelial cells –> carcinoma in situ (localised) –> invasive cervical carcinoma
Define necrosis
Traumatic cell death due to injury or disease
What key features are present in necrosis? (4)
- Cell swollen
- Organelles damaged & destroyed
- Contents released
- Inflammation
Define apoptosis
Programmed cell death
What key features are present in apoptosis? (4)
- Cell shrunken
- Apoptosis bodies formed
- Contents retained
- No inflammation
Give examples of necrosis (3)
Frostbite
Cerebral infarction
Pancreatitis
Give examples of apoptosis (3)
Organ sculpting (separation of fingers & toes of foetus)
Skin cells
Cells lining the gut
How does cancer arise?
p53 detects DNA damage and switches on apoptosis
Lack of apoptosis in cancer
What do you call a benign cancer of glandular/secretory epithelium?
ADENOMA eg colonic/ thyroid adenoma
What do you call a benign cancer of non-glandular/non-secretory epithelium?
PAPILLOMA eg squamous cell papilloma
What do you call a malignant cancer of glandular epithelium?
ADENOCARCINOMA eg adenocarcinoma of breast/ stomach
What do you call a malignant cancer of non-glandular epithelium?
CARCINOMA eg transitional cell carcinoma
What do you call a benign cancer of connective tissue?
-OMA
eg neuroma
What do you call a malignant cancer of connective tissue?
-SARCOMA
eg neurosarcoma
What is a rhabdomyoma?
Benign connective tissue cancer of striated muscle
What is leiomyoma?
Benign connective tissue cancer of SM
What is a chondroma?
Benign connective tissue cancer of cartilage
What is an osteoma?
Benign connective tissue cancer of bone
What type of cancers are ALL MALIGNANT?
Lymphomas - lymphoid cells
Melanoma - melanocytes
Mesothelioma - mesothelial cells
What are the most common embryonic tumours? (2)
- Retinoblastoma (eye)
- Nephroblastoma (renal)
What is Burkitt’s lymphoma?
B-cell lymphoma caused by Epstein Barr virus
What is Hodgkin’s lymphoma?
Malignant lymphoma –> Reed-Sternberg cells present
What is a teratoma?
Tumour made up of all 3 germ layers eg contain hair, teeth, bone
Define neoplasia
Autonomous
Abnormal
Persistent
New growth
Define tumour
Any abnormal swelling (neoplasm, inflammation, hypertrophy, hyperplasia)
What causes cancer?
Mutation that causes cells to:
- divide faster
- not apoptose as fast as other cells
- prevents telomerase shortening - makes cells immortal
What do solid tumours consist of?
- Neoplastic cells
- Stroma
Characteristics of benign neoplasms (6)
- Localised
- Slow growth rate - little mitotic figures
- Non-invasive
- Don’t spread to other sites
- Encapsulated
- Necrosis rare
Characteristics of malignant neoplasms (6)
- All invasive
- Can metastasise
- Rapidly growing - increased mitotic figures
- Irregular borders
- Nuclei stain darkly, vary in size/shape
- Necrosis & ulceration common
In terms of differentiation, what tumours are more aggressive?
Poorly differentiated tumours are MORE AGGRESSIVE than well-differentiated tumours (closely resemble parent tissue)
Define anaplastic
So poorly differentiated they lack histogenic features = EXTREMELY AGGRESSIVE eg anaplastic carcinoma of thyroid
Define carcinoma in situ
Neoplasm that hasn’t invaded through the epithelial basement membrane ie will sit where it is
Complete excision will guarantee a cure
Define invasive carcinoma
Neoplasm has invaded through the basement membrane
What tumours commonly metastasise to the lung?
Sarcomas
Any common cancers
What tumours metastasise to the liver?
Colon
Stomach
Pancreas
Carcinoid tumours of intestine
What tumours metastasise to bone?
Prostate Breast Thyroid Lung Kidney
Which carcinoma never metastasises?
Basal cell carcinoma (rodent ulcer)
