Cancer Flashcards
What is a tumour?
Any kind of mass forming lesion, may be neoplastic, hamartomatous or inflammatory
What is a neoplasm?
Autonomous growth of tissue which have escaped normal constraints on cell proliferation
- a non neoplastic tumour would only be organised in an abnormal way
What are cancers?
Malignant neoplasms
What are the differences between benign and malignant neoplasms?
benign : not attached to skin, must not invade locally
Malignant : irregular margin, invaded tissues locally
Why may benign cancers be more dangerous than malignant ones?
Due to their location, e.g a benign tumour in the brain can press on vital structures.
What are hamartomas?
Localised benign growth of one or more mature cells types
Represent Architectural abnormalities
E.g. lung hamartomas ( composed of cartilage and bronchial tissue )
What are Heterotopias?
Normal tissue found in parts of the body not normally present e.g. pancreas found in wall of large intestine
Tumours
How are neoplasms defined?
Primary description : cell origin
Secondary description : benign or malignant
What is a benign tumour of cartilage called and a malignant tumour?
Chondroma
Chondrosarcoma
Give examples of epithelial neoplasms?
Squamous: squamous papilloma / squamous carcinoma found in skin oesophagus and cervix
Glandular : Adenoma / Adenocarcinoma found in breast, colon, pancreas, thyroid
Transitional : Transitional papilloma / transitional cell carcinoma found in bladder
Give examples of connective tissue neoplasms?
Smooth muscle : leiomyoma / leiomyosarcoma found in uterus and colon
Bone : osteoma / osteosarcoma found in arm and leg
Give examples of Haematological Neoplasms?
Lymphocytes : benign uncommon / lymphoma
Bone marrow : benign uncommon / leukaemia e.g. ALL, CML
What are Teratomas?
Tumours derived from germ cells and can contain cells for all 3 germ cell layers
Can have mature, immature or cancer tissue
What is special about Hepatomas, Melanomas, teratomas?
They end in -oma but they are malignant
What is invasion?
Direct extension into adjacent connective tissue or other structures
Can distinguish between dysplasia and carcinoma from cancer
- severe dysplasia still not cancer
What is Metastasis?
Spread via blood vessels to other parts of the body
- all malignant tumours have capacity to do so
What is differentiation?
How much do the cells resemble cells from which they are derived
How do tumour cells look different?
- larger nuclei
- more mitoses
- abnormalities mitoses e.g. tripolar
- nuclear pleomorphism
- Loss of normal features
What is growth pattern?
How much the arrangement of tumour resembles the tissue from which it is derived
Tumours have less well defined architecture
What is the Gleason grading system?
Architecture changes towards a less well differentiated tumour. ( grade 1-5 for aggresive prostate cancer )
How may benign tumours become malignant?
Hyperproliferation –> adenomatous polyps –> severe dysplasia –> carcinoma –> invasive cancer
Why which routes do tumours spread?
Direct extension Haematogenous Lymphatic Transcoelomic Perinerual
What are examples of direct extension?
Associated with stromal response
Fibroblastic proliferation
Vascular proliferation
Which blood vessels are usually used during haematogenous?
Invaded vessels are venules and capillaries because they have thinner walls
- most sarcomas metastasise first via blood vessels
Which cancers metastasise first via the lymphatics?
Epithelial
Pattern of spread dictated by normal lymphatic drainage of organ in question
Which cavities are involved in transcoelomic spread?
Pleural cavities for intra-thoracic cancers and peritoneal cavites for intra-abdominal cancers
What is the TNM system?
T - tumour ( size/extent of local invasion ) [ 0,1,2,3 ]
N - nodes ( lymphs involved ) [ 0, 1, 2 ]
M - metastases ( How many ) [ 0, I, X ]
What is the difference in grade and stage?
Grade : how differentiated the tumour is
Stage : how far has the tumour spread - TNM
- stage is more important
