Cancer cell pathology Flashcards
(20 cards)
Tumor:
any kind of mass forming lesion
Neoplasm:
abnormal mass of tissue, growth of which is virtually autonomous and exceeds that normal tissues growth uncoordinated and persists after cessation of stimulus
Parenchyma:
cancer cell that has been transformed
Stroma:
tissue around cancer cells consisting of connective tissue, blood vessels, macrophages, lymphocytes
- Support system for cancer cells
How are tumors classified?
- Neoplasm description based on cell origin and secondary defined into malignant/benign
- Benign ones end in oma
- Malignant: either carcinoma (parenchymal) or sarcoma (stromal)
- From glandular tissue: adenoma, cystadenoma, papilloma
- From stromal tissue: fibroma, lipoma, angioma, osteoma/chondroma
- Cancers are malignant neoplasms
What are hamartomas?
- Localized benign overgrowth of more than one mature cell type
- Architectural but not cytological abnormalities
- E.g cartilage in bronchial tissue
What are heterotopias?
- Normal tissue founding parts where not normally present
- Pancreas in wall of large intestine
What is a teratoma?
- Tumors derived from germ cells and contain tissue derive from all three germ cell layers
- Mesoderm, endoderm, ectoderm
- May contain mature or immature tissues and/or cancers
What malignant tumors end in oma?
- Lymphoma
- Melanoma
- Hepatoma
- Teratoma
What are the differences between malignant and benign tumors?
- Differentiation
- How much do cells of tumour resemble cells of tissue derived from
- malignant tumors show anaplasia - benign tumors are relatively well differentiated (Can recognize where tissue came from)
- Tumor cells have larger nuclei (so more nucleus than cytoplasm) more mitosis than normal tissue derived form
- Have abnormal mitoses and marked nuclear pleomorphism - Rate of growth: benign slower
- Local invasion: benign don’t infiltrate basal lamina, malignant do
- direct extension into adjacent connective tissue or structures - Metastasis: benign don’t
- Spread via blood vessels to other parts of body
- All tumors have capacity to metastasize (may be diagnosed before) - Growth pattern:
- How much does architecture resemble architecture of tissue derived from
- Usually less
What are the 4 mechanisms of invasion/metastasis?
- Direct extension:
- Associated with stromal tumor response
- When tumors invade tissue elicit immune/vascular
- Fibroblastic proliferation (desmoplastic response), vascular proliferation and immune response - Hematogenous
- common in sarcomas (metastasize first via blood vessels) e.g epithelial cancers
- Blood vessels invaded usually venules and capillaries because have thinner walls - Lymphatic
- more common for carcinomas
- Drain to lymph node
- Pattern spread dictated by normal lymphatic drainage of organ - Transcoelomic
- Via seeding body cavities
- E.g pleural cavities (intrathoracic) and peritoneal cavities (intra-abdominal) - Perineural
- Nerves
How do we assess tumour spread?
- Clinically
- Radiologically
- Pathologically
How do we describe tumors staged?
TNM
- Size of tumor or extent of local invasion
- Spread to lymph nodes, if yes how many
- Metastasis distant?
What is the difference between grade and stage?
Grade: how differentiated is the tumor (microscope)
Stage: how far has it spread
- For prognosis stage is more important than grade
What is metaplasia?
Substitution of one mature cell type for another mature cell type more suited to the environment
What is dysplasia?
- Loss of uniformity of individual cells
- Loss of their architectural orientation
- Mild to moderate dysplasia may revert to normal
- Severe dysplasia aka carcinoma in situ
What is grading based off of?
- Histological
- Based on the degree of differentiation and on the numbers of mitoses
What are some chemical carcinogens?
- Dimethyl sulphate
- Diepoxybutane
- Cyclophosphamide, chlorambucil, nitrosoureas and other -anticancer drugs
- Beta napthylamine
- Benzidine
- Aflatoxin B1 (grains and peanuts)
- Betel nuts
- Vinyl chloride
- insecticides, fungicides
What are some microbial carcinogens?
- DNA oncogenic viruses HPV, EBV, HBV and HHSV8
- RNA viruses HTLV-1
- Bacterial carcinogens; Helicobacter Pylori
How is cancer diagnosed?
Laboratory methods:
- Cytology FNA (freehand or USS guided)
- Histology (core biopsy, incisional or excisional biopsy)
Tumour typing:
- Immunocyto/histochemistry
- Flow cytometry
- Molecular methods (PCR, FISH)
