Cellular Pathology of Cancer Flashcards
Define Metaplasia:
A reversible change in which one adult cell type (usually epithelial) is replaced by another adult cell type
What is Barrett’s Oesophagus?
Change in the oesophageal epithelium from stratified squamous to simple columnar due to gastro-oesophageal reflux
What type of Physiological metaplasia occurs during pregnancy?
When the cervix opens during pregnancy the columnar epithelium of the endocervical canal is exposed to the acidic uterine fluids making it become more squamous.
When the cervix closes up the cell type reverts, hence why metaplasia is reversible
Define Dysplasia:
An abnormal pattern of growth in which some of the cellular and architectural features of malignancy are present
What is the key architectural feature of dysplasia?
Dysplasia is in a pre-invasive stage with an intact basement membrane
What are common cellular features of dysplasia?
Large and hyperchromatic nuclei
Increased and abnormal mitoses
increased nucleo-cytoplasmic ratio
Mitotic figures are abundant, abnormal, and in places where they aren’t usually found
Name six sites where dysplasia is common and what it is due to:
Bronchus - Smoking
Larynx - Smoking
Oesophagus - Acid reflux
Stomach - Pernicious anaemia
Cervix - HPV infection
Colon - Ulcerative collitis
What features of this cervical biopsy indicate dysplasia?
Left is normal: Compact at bottom then more spaced out towards lumen
Right: Cells not maturing - Compact cells w/dark, dense nuclei on the surface which are normally seen further down
What is the difference between low-grade and high-grade dysplasia?
Both show changes of dysplasia, but the changes are more severe in high-grade - bigger nuclei and higher nucleo-cytoplasmic ratio
What is the significance of Low and High-grade dysplasia?
Low-grade: Low risk of progression to cancer
High-grade: High risk of progression to cancer
Define Neoplasia:
Any new growth - benign or malignant
Define Malignancy:
An abnormal, autonomous proliferation of cells, unresponsive to normal growth control mechanisms
What is the main definition of Benign tumours?
They do not invade and do not metastasise
What are four common features of Benign Tumours?
They are encapsulated - have a compressed capsule around them
They are usually well-differentiated - they look like the tissues they came from
They are slow-growing
They have normal mitoses
What are the six ways Benign tumours may be fatal?
Give an example for each:
Dangerous Location: Meninges, pituitary
Secrete something dangerous: insulinoma
Cause infection: bladder
Bleeds: stomach
Ruptures: Liver adenoma (can cause massive haemoperitonium)
Torts (twists): ovarian cyst
Define Metastasis:
A discontinuous growing colony of tumour cells at some distance from the primary cancer
What is the main definition of Malignant tumours?
Invade surrounding tissues and spread to distant sites
What are four common features of malignant tumours?
No capsule
Well to poorly differentiated
Rapidly growing
Abnormal mitoses
What determines the site of metastasis?
The lymphatic and vascular drainage of the primary site
What determines the prognosis of malignant cancer?
Whether it has spread
Whether it has involved the lymph nodes
Name seven types of tumour classifications:
Benign epithelial tumours
Carcinomas
Benign soft-tissue tumours
Sarcomas
Leukaemia & Lymphoma
Teratoma
Hamartoma
What are Benign Epithelial tumours of the surface of the epithelium known as?
Where may they be found?
Papillomas
Skin, Bladder
What are benign epithelial tumours of the glandular epithelium known as?
Where may they be found?
Adenomas
Stomach, Thyroid, Colon, Kidney, Pituitary, Pancreas
What is a carcinoma?
A malignant tumour derived from the epithelium
What is a Benign Glandular epithelial tumour that becomes malignant known as?
Adenocarcinoma
How are carcinomas classified?
Name four types:
By the tissues they came from:
Squamous cell carcinoma
Adenocarcinoma
Transitional cell carcinoma (transitional epithelium found in the bladder)
Basal cell carcinoma
Name three types of benign soft tissue tumours and where they come from:
Osteomas - Bone
Lipomas - Fat
Leiomyomas - Smooth muscle
What is a sarcoma?
A malignant tumour derived from connective tissue (Mesenchymal cells)
What are 6 types of connective tissue a malignant tumour can come from?
Name the type of cancer for each:
Fat - Liposarcoma
Bone - Osteosarcoma
Cartilage - Chondrosarcoma
Striated muscle - Rhabdomyosarcoma
Smooth muscle - Leiomyosarcoma
Nerve sheath - Malignant Peripheral Nerve Sheath Tumour
What is Leukaemia?
Malignant tumour of Bone Marrow derived cells which circulate in the blood
What is Lymphoma?
Malignant tumour of Lymphocytes (usually) in Lymph nodes
What is a mix of Lymphoma and Leukaemia?
Malignant tumours of lymphocytes produced in the bone marrow that are found in the lymph nodes
What is a Teratoma?
A tumour derived from Germ Cells which has the potential to develop into tumours of all three germ cell layers
(Ectoderm Mesoderm + Endoderm)
What are the three Germ cell layers?
Ectoderm, Mesoderm and Endoderm
What are the patterns of malignancy in Gonadal teratomas between males and females?
In Males - almost always Malignant
In females - mostly benign
What is a Hamartoma?
Localised overgrowth of cells and tissues native to the organ
- Cells are the appropriate type, but are architecturally abnormal
What are the two methods of differentiation of tumours?
Staging and Grading
What is tumour grading?
How poorly differentiated they are
What is tumour staging?
How far the tumour has spread
What are tumours that show little or no differentiation described as?
Anaplastic
What are four morphological features that can be used to determine how differentiated a tumour is?
Production of:
Keratin (Squamous cells)
Mucin (Glandular epithelium)
Bile (Hepatocytes)
Hormones
What is more important in determining cancer prognosis, Grade or Stage?
Stage
(High stage often = high grade)
