Neoplasia and Cancer Pathology Flashcards
What is the difference between neoplasia and cancer?
Neoplasm can be benign (eg. BPH) or malignant (Cancer)
True or False. Tumours are often accompanied by blood vessels and connective tissue.
True
How can benign tumours complicate?
1) Site (eg. meningioma –> ^ intracranial pressure)
2) f(x) (eg. insulinoma –> hypoglycaemia)
What are the 4 main characteristic of benign tumours?
1) slow growth rate (by compression of surrounding tissue)
2) no infiltration, vascular invasion, or metastasis
3) High px survival rate after surgical excision
4) well-differentiated, resembling normal tissue of origin (uniform appearance)
Are all “-omas” benign?
No.
eg. Sarcoma, Carcinoma, Lymphoma, Hepatoma, Melanoma
Are malignant tumours well or poorly differentiated?
Poorly differentiated –> less resemblance to parent tissue
What are the 4 main characteristics of malignant tumours?
1) rapid growth rate (by invasion of surrounding tissue)
2) metastasizing
3) poor px survival rate after surgical excision + tendency for recurrence (local or distant
4) poorly-differentiated, irregular structures
What do multiple necrotic or discoloured circles in resected organs usually indicate?
Tumour metastasis
What are Blastomas?
Generally aggressive malignant tumours
What are the distinctive histological features of Blastomas?
Rosettes (primitive looking structures) which are small round cell tumours
What are Teratomas?
Tumours arising from totipotent germ cells in gonads
Where are Teratomas usually form?
Gonads (eg. testes, ovaries)
What are some local effects that can result from GIT-related tumours?
Obstruction, Perforation, Ulceration
How can a tumour result in a non-healing ulcer?
Destruction of epithelial surfaces (eg. GIT, mouth, bronchi)
Why do tumours cause pain and when would they not?
When tumours form/invade sites with sensory nerve endings.
They are initially painless only when in the brain and viscera.
What are the 3 broad clinical effects of Cancer?
1) Local/mechanical
2) Endocrine
3) Cancer cachexia
What are some possible endocrine effects of tumours?
1) Endocrine tumours producing excessive hormones
2) Paraneoplastic syndrome
3) Loss of f(x) by compression/destruction
What is cancer cachexia/wasting syndrome?
1) Cytokine-related (TNF, IL-1) progressive fat loss due to proteolysis-inducing factor
2) Anorexia due to excessive cytokine release
3) Anaemia w weakness due to autoimmunity or excessive bleeding
How can tumours cause edema?
Venous or lymphatic obstruction (eg. tumour embolism)
What is “paraneoplastic syndrome”?
Symptom complexes that are not attributable to:
(i) local or (ii) distant spread
(iii) hormonal effects indigenous to tissue of origin
What are some examples of paraneoplastic syndromes?
1) Endocrinopathies (eg. Cushing’s syndrome, SIADH, HyperCa2+)
2) Nerve and Muscle Syndromes (eg. Myasthenia, CNS/PNS disorders)
3) Dermatologic disorders (eg. Dermatomyositis, Acanthosis nigricans)
4) Osteoarthropathy and finger clubbing
5) Hematologic changes (eg. Anaemia, Thrombosis, non-bacterial thrombotic endocarditis)
What are tumour markers?
They are enzymes, hormones, oncofetal Ag that are used in biomarker assays in the screening of cancers.
Can tumour markers be used for definitive diagnosis?
No
What are the uses of tumour biomarker assays?
1) Detection of cancers
2) monitoring residual/reccurent tumours post therapy
What are the types of tumour markers?
1) Hormones (eg. HCG, Calcitonin, Catecholamines, metabolites)
2) Oncofetal Ags (eg. AFP, CEA)
3) Isoenzymes (eg. Prostatic acid phosphatase, Neuron-specific enolase)
4) Proteins (eg. Igs, PSA)
5) Glycoproteins (eg. Mucins, CA-125/19-9/15-3)
6) p53, RAS mutations (in serum, sputum, stool, urine)
What is Dysplasia?
Premalignant conditions resulting from disordered growth in epithelia
Do all dysplasia progress to malignant tumours?
No, but it does predispose to cancer development
What is the risk of px with Familial Adenomatous Polyposis (FAP) developing colon cancer?
100%
What is the gene that causes FAP
APC gene (AD inheritance)
What Virus can cause dysplasia?
Human Papillomavirus (HPV)
How are cervical cancers screened for?
PAP smears for dysplastic cells
How are tumours staged and graded?
Histologically
What is the difference between tumour staging and grading?
Grading refers to the degree of differentiation
Staging refers to the degree of metastasis
What is the significance of tumour staging
Higher stage cancers are more aggressive and have worse prognosis
This is impt for px counselling and treatment (need adjuvant)
What is the TNM system?
The staging system to describe the invasiveness of the tumour.
T - tumour in primary site
N - Lymph nodes, regional
M - distant metastases
What are the grades of a malignant tumour?
Grade 1: Well differentiated
Grade 2: Moderately differentiated
Grade 3: Poorly differentiated
*Some have grade 4
How are tumours disseminated?
1) Local infiltration
2) Spread through body cavities (eg. seeding in body cavities, pagetoid/epithelial linins, Perineural infections)
3) Lymphatic spread
4) Hematogenous spread (eg. GIT–> Liver via portal vein, to Lung vis caval vein, to spine via paraverterbral venous plexus, to brain via arteries)
Are enlarged regional lymph nodes indicative of metastatic cancer spread?
No, it could be a reactive hyperplasia to tumour Ags, or some other infection.
Are the presence of only isolated cells in regional draining lymph nodes indicative of metastatic cancer spread?
No
What type of cells form Carcinomas?
Epithelial Cells
What cells form Sarcomas?
Endothelial cells
What cells form Melanomas?
Melanocytes
What cells form Lymphomas?
Lymphocytes (B or T cells)
What cells form Lipomas?
Adipocytes
What cells form Chondrosarcomas?
Cartilage
What cells form Fibrosarcoma?
Fibrous Tissue
What cells form Leiomyoma?
Smooth Muscle cells
What cells form Haemangioma
Vascular endothelial cells
What is a adenocarcinoma?
A gland forming malignant tumour
What is a fibroadenoma?
A benign tumour formed from both fibrous and glandular tissue.
What are the key histological features of malignant cells?
Infiltrative growth/Not well-circumscribed
Poorly differentiated/Anaplasia
High/abnormal mitosis
Hyperchromasia w large nucleolus and clumped chromatin
Pleomorphism
High N/C ratio
Metastasis
Necrosis and haemorrhage common
What are the key histological features of benign tumours?
Non-infiltrative/compressive growth/Well-circumscribed
Well-differentiated
Few mitoses
Rare necrosis and haemorrhage
What are the 4 key histological features of a Carcinoma?
1) Keratinisation
2) Keratin pearls
3) Intercellular Bridging
4) Cell Shape + eosinophilic cytoplasm
What is the key histological feature of a Adenoma?
Intracellular mucin
What differentiates a Carcinoma from a Carcinoma in-situ?
Carcinoma in-situ has yet to breach any basement membrane to invade underlying stroma
What does the suffix “-oma” imply?
Epithelial or Mesenchymal origin
What does the prefix “Adeno-“ imply?
Glandular origin
