tumour classification Flashcards
outline the difference between the terms neoplasm and tumour
tumour = anything that causes an abnormal swelling, for example, inflammation, neoplasm, hypertrophy or hypotrophy
neoplasm = a localised abnormality from an abnormal growth of cells which persists after the initiating stimulus has been removed
define neoplasm
A lesion (localised abnormality) resulting from the autonomous or relatively autonomous abnormal growth of cells which persists after the initiating stimulus has been removed.
- it is persistent and no longer needs an initiating event to grow
what are the 2 main structural components of a neoplasm?
- neoplastic cel
- stroma
what are the 3 behavioural classifications of neoplasm?
Benign
Borderline
Malignant
however its pretty much a scale and not always a set catagory
What is the role of the neoplastic cell in a neoplasm?
- known as the tumour cellswhich drives the neoplasms growth
- Makes up the proliferating abnormal cells
- Determines the biological behaviour and tumour type (e.g., carcinoma or sarcoma).
What is the role of the stroma in a neoplasm?
- non-cancerous supportive tissue that surrounds and interacts with the neoplastic cells
- Provides structural support and supplies nutrients, oxygen, and growth signals.
- Includes connective tissue, blood vessels, and inflammatory cells.
what type of cells are neoplastic cells derived from and what determines their growth pattern?
- Derive from nucleated cells
- Usually monoclonal
- Growth pattern and synthetic activity related to parent cell
which characteristics do we use to classify neoplasms?
Behavioural - Benign/Malignant
Histogenetic - Cell of origin
degree of classification - how much they resemble normal tissue
outline the characteristics of malignant neoplasms?
- Invasive
- Metastases - process of cancer cells spreading from origin and invading
- Rapid growth rate
- Variable resemblance to normal tissue
- Poorly defined or irregular border on histology slides compared to normal tissue
what microscopic structural characteristics do malignant neoplasms have?
- Hyperchromatic nuclei
- Pleomorphic nuclei (variation in size, shape and structure)
- Increased mitotic activity
- Necrosis and ulceration common
- Growth on mucosal surfaces and skin often endophytic
why are benign neoplasms still a potential cause for concern?
- Pressure on adjacent structures
- Obstruct flow
- Produce hormones
- Transform to malignant neoplasm
- Anxiety
what are the characteristics of benign neoplasms?
- Localised, non-invasive
- Slow growth rate
- Low mitotic activity
- Close resemblance to normal tissue
- Circumscribed or encapsulated
- Nuclear morphometry often normal
- Necrosis is rare
- Ulceration is rare
- Growth on mucosal surfaces usually exophytic (projecting outwards, eg moles)
define histogenesis.
The specific cell of origin of a neoplasm
when would the term adenoma be used to describe a neoplasm?
- Benign neoplasm of glandular or secretory epithelium
- Prefix with cell type of origin, e.g. colonic adenoma, thyroid adenoma
what are the 2 names to describe benign epithelial neoplasms?
- adenoma
- papilloma
when would the term papilloma be used to describe a neoplasm?
- Benign neoplasm of non-glandular non-secretory epithelium
- Prefix with cell type of origin, e.g. squamous cell papilloma
what is the term given to malignant epithelial cancer?
- carcinoma
what is the term given to carcinomas of glandular epithelium?
adenocarcinomas
what are the terms given to benign connective tissue neoplasms, adipocytes, cartilage, bone and vascular, striated muscle, smooth muscle and nerves and how would these names differ if the cancer was malignant?
Lipoma: adipocytes
Chondroma: cartilage
Osteoma: bone
Angioma: vascular
Rhabdomyoma: striated muscle
Leiomyoma: smooth muscle
Neuroma: nerves
if cancer was malignant it would have “sarcoma” instead of “oma”
define anaplastic
Where cell type of origin cannot be determined, the neoplasm is said to be anaplastic
exceptions to the rule
- Not all ‘-omas’ are neoplasms
e.g. granuloma, mycetoma, tuberculoma - Not all malignant neoplasms are carcinomas or sarcomas, e.g.:
Melanoma: malignant neoplasm of melanocytes
Mesothelioma: malignant neoplasm of mesothelial cells
Lymphoma: malignant neoplasm of lymphoid cells - some neoplasms are named after someone eg burkitt lymphoma
- embryonal neoplasms
- mixed neoplasms
Define the incidence of neoplastic disease.
The incidence of neoplastic disease refers to the number of new cases of neoplasms (tumors, which can be benign or malignant) diagnosed in a specific population over a defined period, typically expressed as a rate per 100,000 individuals per year.
For example:
“The incidence of breast cancer in a given region may be 125 cases per 100,000 women per year.”
Incidence helps measure the risk of developing neoplastic diseases and is often used in epidemiological studies to track trends and allocate healthcare resources.
