Benign and Malignant Tumours: Tumour classification Flashcards
what does tumour mean?
any abnormal swelling
what can cause swelling?
Neoplasm
Inflammation
Hypertrophy
Hyperplasia
describe neoplasms
A lesion resulting from the autonomous or relatively autonomous abnormal growth of cells which persists after the initiating stimulus has been removed.
always a new growth
what is a lesion
a localised abnormality that results from the autonomous …..
what are neoplastic cells derived from?
nucleated cells usually monoclonal
describe the structure of neoplasms
neoplastic cells surrounded by the stroma providing support for the neoplastic cells.
describe the growth pattern of neoplastic cells
the growth pattern and synthetic activity will be related to parent cell
e.g- if from thyroid, will grow like thyroid and may even produce same hormone
describe the stroma in neoplasms
Gr. = mattress
Connective tissue framework
provides mechanical support and nutrition
tumour angiogenesis
Why is it important to classify neoplasms?
To determine appropriate treatment
To provide prognostic information
To aid communication
How are neoplasms classified?
Behavioural
Benign/Malignant
Histogenetic
Cell of origin
How are neoplasms classified in terms of their behaviour?
benign
borderline
malignant
Describe benign neoplasms
Localised, non-invasive
Slow growth rate
Low mitotic activity
Close resemblance to normal tissue
Circumscribed or encapsulated
Describe the histological features of benign neoplasms
Nuclear morphometry often normal
Necrosis rare
Ulceration rare
Growth on mucosal surfaces usually exophytic- tend to grow up and outwards
Why worry about benign neoplasms?
Cause morbidity and mortality by:
-Pressure on adjacent structures
-Obstruct flow
-Produce hormones
-Transform to malignant neoplasm
-Anxiety
Describe malignant neoplasms
-Invasive- surrounding tissue- in lymphatic,vessels,nerves therefore can metastasise
-Metastases- not a defining feature as some malignant neoplasms never metastasise
-Rapid growth rate- easy to find mitotic figueres
-Variable resemblance to normal tissue- more aggressive-less resembalance
-Poorly defined or irregular border
Describe the histological features of malignant neoplasms
-Hyperchromatic ( darker than normal) nuclei
-Pleomorphic ( larger than normal) nuclei
-Increased mitotic activity
-Necrosis and ulceration common
-Growth on mucosal surfaces and skin often endophytic-( down and inwards)
Why worry about malignant neoplasms?
Cause morbidity and mortality
-Destruction of adjacent tissue
-Metastases
-Blood loss from ulcers
-Obstruct flow
-Produce hormones
-Paraneoplastic effects- ( effects at different sites)
–Anxiety and pain
define histogenesis
The specific cell of origin of a neoplasm
what cells do neoplasms arise from?
-Epithelial cells (most common)
-Connective tissues
-Lymphoid/haematopoietic organs
for neoplasms what suffix is used?
-Oma
for neoplasms what prefix is used?
depends on behavioural classification and cell type
Describe what a Papilloma is
-Benign neoplasm of non-glandular non-secretory epithelium
-Prefix with cell type of origin, e.g. squamous cell papilloma
Describe what an Adenoma is ?
-Benign neoplasm of glandular or secretory epithelium
-Prefix with cell type of origin, e.g. colonic adenoma, thyroid adenoma
