Oncology 1 Flashcards
Stages of cancer diagnostics
- diagnosis- what is it?
- Staging- How far has it gone?
- Treatment- What to do with it?
Potential diagnostic tests
- FNA
- Biopsy
- Bone marrow sampling
4.Clonality test - Flow cytometry
Fine needle aspirate
First diagnostic test that should be conducted
-use 22-23G needle
-can use ultrasound guided
Mast cell tumours and FNA
-release histamines as soon as they are poked with FNA technique
=brusing, reaction= give antihistmines immediately
Cytology tips
- Are there nucleated cells?
- Is the population uniform?
- What type of cells are they?
- Malignancy criteria?
Cancer cell types
- Epithelial
- Mesenchymal
- Round cell tumor
Epithelial tumours
-Arise from the cell of surface layer (organs, glands, skin)
=adenomas and carcinomas
-will be clustered together (“want to hold hands”)
Mesenchymal tumors
-will be spread out (“no tight connections between cells”)
-tail present
=sarcomas (from fibrous tissue, nerves, etc.)
Round cell tumors
-Cancers of blood
-Round, individualized (don’t need to be clumped together)
Round cell tumors DDx
-lymphoma
-Mast cell tumor
-Histiocytic sarcoma
-Histiocytoma
-Plasma cell tumour
-Melanoma
-Transmissible venereal tumour
Mesenchymal tumour
Round cell tumour
-this one is mast cell tumour (see granules)
Round cell tumor
Lymphoma
Mast cell tumours
Histiocytic sarcoma
Plasma cell tumours
Melanoma
Histopathology
Collect tissue biopsy/sample of the mass
-can tell us about the border and invasiveness of the tissues
Adenoma vs adenocarcinoma in histopathology
Adenoma= very clear border
Adenocarcinoma= no clear border, invasive into normal tissues
Potential tissue biopsy methods
- Tru-cut- used to prevent bleeding
- Punch- superficial
- Wedge- when can’t do punch or when tumor is large
- Excisional- used when tumour is small
When should you do a biopsy?
-When differential diagnosis makes sense
-If the result will change the case management
Biopsy for plasma cell tumors or histiocytoma?
Excise immediately
Biopsy for histiocytic sarcoma soft tissue sarcoma, hemangiosarcoma?
Treat differently
Parts of a histopathology report
- Diagnosis
- Grade, Mitotic count
- Margins
What should be the next step if results do not fit?
Ask for a second opinion
-See major clinical decision 17-39%
-See minor clinical decision= 14-21%
Immunohistochemistry (IMC)
- Diagnostic confirmation
- Prognosis
Cancers appearing on bloodwork, not as a mass
May see cytopenia, increased cell count, circulating atypical cells, monoclonal gammopathy
Bone marrow sampling
Use needles under GA/sedation and gain cavity
-common in humerus, ileus, ileus to wing
Lymphocytes- Neoplastic vs Reactive
- Makes it hard to differentiate
-cancel out with either PCR or flow cytometery
PCR
Lymphoma cells, Reactive lymphocytes and non-lymphatic cells have different bands appearing on PCR
Cell markers for PCR
B cell= Ig
T cell: TCR
Lymphoma is…
monoclonal
Reactive lymphocytes
Polyclonal cells
Flow cytometery
*Used for lymphocytic cancers
1. lymphocytes in fluid
2. When cell passes through tube, they can be grabbed
**cells must be alive
Cancer screening
Cancer mutation genes leak contents into the blood and tests can detect their presence
