Histopathology Flashcards
What is meant by neoplasia?
New growth which is abnormal. Its proliferation of cells leads to a tumour.
What is meant by hyperplasia?
Increase in cell number, proportional to stimulus.
What is meant by hypertrophy?
Increase in cell size, proportionate to stimulus.
What is meant by choristoma?
Tumour composed of normal cells/tissues present in abnormal cell.
What is meant by hamartoma?
Tumour composed of disorganised growth of different cell types normally present in organ. e.g. growth of fat/cartilage in lungs.
What is meant by teratoma?
Tumour composed of derivatives of 3 embryological layers e.g. ectoderm, mesoderm, endoderm.
What is meant by dysplasia?
Growth of abnormal cells before they become cancerous.
State 4 types of cancer.
Carcinoma. Lymphocytes. Leukemia. Lymphoma. Sarcoma. Adenoma. Papilloma. Mesothelioma.
What is meant by a carcinoma?
Originate in skin, lungs, breasts, pancreas.
What is meant by a lymphocytes?
Cancers of lymphocytes.
What is meant by a leukemia?
Cancer of the blood.
What is meant by sarcoma?
Arise in bone, fat, blood vessels, cartilage, connective tissue.
What is meant by an adenoma?
Tumour of glandular tissue e.g. mucosa of stomach, small intestine, colon.
What is meant by a papilloma?
Benign growth on epithelium of the skin - warts/verrucae.
What is meant by an mesothelioma?
Tumour in layers of tissue that cover the lungs (pleura) - linked to asbestos exposure.
State 3 differences between benign and malignant cells.
Benign are close to the origin where as, malignant are spread out. Benign have a uniform growth pattern, where as malignant has irregular/hazardous growth. Benign has normal nuclear size, where as malignant nuclear size is enlarged. Benign has no increase in tumour cells during mitosis, while malignant has an increased number of tumour cells. Benign have no necrosis/haemorrhage or fibrotic reaction, where as malignant do.
State 3 ways of genetic damage in cancer.
Point mutation. Translocation. Deletion. Gene amplifications. Polysomy.
State 2 classes of carcinogenic genes.
Proto-oncogenes. Tumour suppressor genes. Genes that regulate programmed cell death. Genes involved with DNA repair.
State 3 routes by which tumours can metastasise.
Via lymphatics. Via bloodstream. Via extravascular migratory metastasis. Perineurally (near nerves). Trans-peritoneally (through peritoneum). Areogenous (transmission through air). By fluid e.g. urine.
What is meant by cytology?
Study of cells.
What is meant by an histology?
Study of tissues.
State 2 ways cytology is carried out.
Naturally exfoliated - urine, sputum. Artificially exfoliated - washings, bruisings, scrapings. Fine needle aspiration (FNA) - guided by imaging technique.
State 2 investigations of tissue.
Punch/forceps biopsy - mucosal/skin surface. Core biopsy - deeper lesions. Incision - skin/fibre-optic endoscopy imaging. Radial surgical resection - symptomatic relief.
State 2 techniques used in histology.
Immunohistory - staining antigens on surface. Flow cytometry - sample suspended in a fluid and injected into a flow instrument. Molecular diagnostics - cytogenetics.
What is meant by a tumour grade?
How closely it resembles the cell of origin.
Do well-differentiated tumours have a low or high grade?
Low grade - good prognosis.
Do poorly-differentiated tumours have a poor or high grade?
High grade - poor prognosis.
