Oncology Flashcards
Definition of tumour
Abnormal swelling - it is a cardinal feature of inflammation
Definition of neoplasms
A lesion which results from autonomous or relatively autonomous abnormal growth of which persists after the initiating stimulus has been removed.
What are four features of neoplasms
- Autonomous
- Abnormal
- Persistant
- A new growth
- Derived from nucleated cells
- Usually monoclonal
- Growth pattern is related to the parent cell
- Synthetic activity is related to parent cell (secretes same hormones, collagen etc).
What percentage of UK deaths are due to neoplasms?
20%
Highest prevalent cancers in males and females respectively:
Males - prostate, lung, bowel
Females - breast, lung, bowel
Cancers most likely to kill males and females respectively:
Males - lung, prostate, bowel
Females - lung, breast, bowel
Why do some fast growing tumours have necrotic tissue within the centre of them?
The tumour grows at a faster rate than the tumour angiogenesis process so some tissue is left without blood supply and becomes necrotic.
How can neoplasms be classified?
- Behavioural (benign, borderline, malignant)
2. Histogenetic
Three features of benign neoplasms
- Localised and non-invasive
- Slow growth rate
- Low mitotic activity
- Close resemblance to normal tissue
- Circumscribed or encapsulated
- Normal nucleus
- Necrosis and ulceration is rare
- Growth on mucosal surface
- Exophytic (grow outwards as they cant invade tissue)
How do benign neoplasms cause morbidity or mortality?
- Pressure on adjacent structures
- Obstruct blood flow
- Obstruct bowel
- Produce hormones
- Can transform into malignant neoplasms
- Cause anxiety
Three features of malignant neoplasms
- Always invasive
- Can be metastatic
- Rapid growth rate
- Variable resemblance to normal tissue
- Poor/irregularly defined border
- Hyperchromatic nuclei
- Pleomorphic nuclei
- Increased mitotic activity
- Necrosis and ulceration is common
- Endophytic
How do malignant neoplasms cause morbidity or mortality?
- Encroach and destroy surrounding tissue
- Destruction of adjacent structures
- Metastases cause damage to other areas of the body
- Blood loss through ulceration
- Obstruction of structures/blood flow/bowel
- Hormone production
- Paraneoplastic effects
- Anxiety and pain
Define papilloma
Benign tumour of non-glandular or non-secretory epithelium e.g. squamous cell papilloma
Define adenoma
Benign tumour of glandular or secretory epithelium e.g. thyroid adenoma
Define carcinoma
Malignant tumour of epithelial cells e.g. transitional cell carcinoma
Define lipoma
Benign tumour of adipocytes
Define chondroma
Benign tumour of cartilage
Define osteoma
Benign tumour of bone
Define angioma
Benign tumour of vasculature
Define rhabdomyoma
Benign tumour of striated/skeletal muscle
Define leiomyoma
Benign tumour of smooth muscle
Define liposarcoma
Malignant tumour of adipocytes
Define chondrosarcoma
Malignant tumour of cartilage
Define osteosarcoma
Malignant tumour of bone
Define angiosarcoma
Malignant tumour of vasculature
Define rhabdomyosarcoma
Malignant tumour of striated/skeletal muscle
Define leiomyosarcoma
Malignant tumour of smooth muscle
Are granulomas, mycetomas and tuberculomas neoplasms?
No.
Granuloma - mass of granulation tissue in response to infection
Mycetoma - ball of fungus within the body cavity
Tuberculoma - clinical manifestation of tuberculosis
Define melanoma
Malignant neoplasm of melanocytes
Define mesothelioma
Malignant neoplasm of mesothelial cells
Define lymphoma
Malignant neoplasm of lymphoid tissue
Give three exceptions to the naming rules for tumours
- Melanoma
- Mesothelioma
- Lymphoma
- Teratoma
- Blastoma
- Mixed tumours
- Carcinosarcoma
- APUDomas
- Tuberculoma
- Granuloma
- Mycetoma
- Burkitt’s lymphoma
- Edwing’s sarcoma
- Grawitz tumour
- Kaposi’s sarcoma
What is the difference between carcinogenic and oncogenic?
Carcinogenic - cancer causing
Oncogenic - tumour causing
What is carcinogenesis?
The transformation of normal cells to neoplastic cells through permanent genetic alterations or mutations. The term only applies for malignant neoplasms.
What are carcinogens?
Agents known or suspected to cause tumours.
What percentage of cancer risk is environmental?
85%
What is the first and second most common causes of cancer?
Smoking
Obesity
What are the 5 types of carcinogens?
- Chemical - some chemicals act directly as carcinogens, some are metabolised in the body from procarcinogens to ultimate carcinogens
- Viral - hepatitis B/C
- Ionising and non-ionising radiation - UV light
- Hormones, parasites, mycotoxins - oestrogen can cause mammary and endometrial cancer. Steroids are associated with hepatocellular carcinoma, Chlonorchis sinensis is associated with cholangiocarcinoma (parasite and bile duct cancer)
- Miscellaneous - asbestos ans metals
What are some host factors which affect our cancer risk?
- Race
- Diet
- Constitutional factors (age, gender)
- Premalignant lesions (colonic polyps, cervical dysplasia, ulcerative colitis, undescended testis)
- Transplacental exposure
