Neoplasia 1&2 Flashcards
Define malignant neoplasia
The abnormal growth of cells, which persist after the initiating stimulus has been removed and invades and spreads to distant sites (metastasis)
Define benign neoplasia
The abnormal growth of cells, which persists after the initiating stimulus has been removed
Describe the physical difference in benign and malignant neoplasms
Benign neoplasms are rounded masses due to the pushing growth, and remain at the site of origin
Malignant neoplasms are irregular masses due to infiltrative growth, and may spread to distant sites forming secondary growths (metastases)
A mutation in which genes can cause neoplasia?
Proto-oncogenes (permanently activated to oncogenes) or Tumour Suppressor Genes (permanently inactivated)
What key differences do neoplastic cells have from normal cells?
Self sufficient growth signals Resistance to anti-growth signals Grow indefinitely Induce new blood vessels Resistance to apoptosis Invade and produce metastases
Describe the clonality of neoplasms
They are monoclonal as the cell population descends from a common ancestral cell which originally acquired the mutation.
How do benign and malignant tumours differ?
Benign: pleomorphism (variation in size/shape) is minimal, low mitotic count, mitoses have normal form, retention of tissue specialisation (well differentiated)
Malignant: variable pleomorphism, higher mitotic count, mitoses may have abnormal forms, variable loss of tissue specialisation (well to poorly differentiated)
Define tumour
Any clinically detectable lump or swelling
Define cancer
Any malignant neoplasm
Distinguish between in-situ and malignancy
In-situ has all the features of a malignant neoplasm but there is no invasion through the basement membrane.
How are neoplasms classified/named?
By whether they are benign or malignant, and by tissue type.
What is Squamous papilloma
A benign neoplasm of stratified squamous epithelium.
Tumour has finger like projections.
Eg. Skin, buccal mucosa
What is transitional papilloma?
Benign neoplasm of transitional epithelium
Eg. Bladder mucosa
What is an adenoma?
Benign neoplasm of glandular epithelium
Eg. Adenomatous polyp of colon
What is squamous cell carcinoma?
Malignant neoplasm of squamous epithelium
Eg. Skin, larynx, oesophagus
What is transitional cell carcinoma?
Malignant neoplasm of transitional epithelium
Eg. Bladder, uterus
What is adenocarcinoma?
Malignant neoplasm of glandular epithelium eg. Stomach, colon, lung, prostate, breast, pancreas
What is basal cell carcinoma?
Malignant neoplasm of basal cells eg. in skin
What is leiomyoma?
Benign neoplasm of smooth muscle
What is leiomyosarcoma?
Malignant neoplasm of smooth muscle
What is fibroma?
Benign neoplasm of fibrous tissue
What is fibrosarcoma?
Malignant neoplasm of fibrous tissue
What is osteoma?
Benign neoplasm of bone
What is osteosarcoma?
Malignant neoplasm of bone
What is chondroma?
Benign neoplasm of cartilage
What is chondrosarcoma?
Malignant neoplasm of cartilage
What is lipoma?
Benign neoplasm of adipose tissue
What is liposarcoma?
Malignant neoplasm of adipose tissue