Histopath LEC - Diagnostic Cytology PDF

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Summary

DIAGNOSTIC CYTOLOGYDiagnostic cytology The microscopic examination of cells from different body sites for diagnostic purposes Used to diagnose various types of cancer and certain infections Specimen may be derived from various sources: o Exfoliative cytology o Fine needle aspiration (FNA) o Body flu...

Description

DIAGNOSTIC CYTOLOGY Diagnostic cytology - The microscopic examination of cells from different body sites for diagnostic purposes - Used to diagnose various types of cancer and certain infections - Specimen may be derived from various sources: o Exfoliative cytology o Fine needle aspiration (FNA) o Body fluids Exfoliative cytology - The microscopic study of cells that have been desquamated from epithelial surfaces - Specimen collected by lightly scraping the surface, by swabbing, aspirating or washing the surfaces o Cervical smear o Vaginal smear o Endometrial smear Recommended for the following: - Detection of malignant cells in body fluids (i.e. cancer staging) - Detection of precancerous cervical lesions in women (i.e. Pap smear) - Assessment of female hormonal status in case of sterility and endocrine disorders - Determination of genetic sex (i.e. detecting Barr bodies) - Detection of infectious agents -

Specimens for examination: Peritoneal, pericardial and pleural fluids CSF Nipple discharge Bronchial brushings / washings Sputum Gastric washings Urine sediments Prostatic secretions / fluid Cervicovaginal (Pap) smear

Cervical smear -

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A screening test for cervical cancer which may be detected even at the pre-invasive stage Involves the microscopic examination of cell samples that have been taken primarily from the ectocervix and endocervix, smeared on glass slides and stained by Papanicolaou (Pap) method May be collected using cotton swabs, wooden or plastic spatula and cervical brushes (or cytobrushes) o Cytobrushes are used strictly for taking materials from the endocervix Cotton swabs o Use is discouraged due to drying artifacts and loss of cells Spatula o Wooden is preferred over plastic, due to its mildly rough surface Cytobrushes o More endocervical cells and blood may be present in smears evaluation  difficulties

Impression smear -

Used for ulcerated surface lesions, to allow an immediate assessment of the lesion before fixation and processing of the tissue sample Also indicated in the case of tumors, especially lymph nodes

Sputum smear -

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Purpose: to detect Mycobacteria in sputum Also known as acid fast bacilli (AFB) test or tuberculosis (TB) smear Instructions are as follows: o Obtain at least three consecutive morning sputum specimens by deep cough method o Collect early morning sputum by a deep cough in a wide-mouthed jar containing Saccomanno fluid (50% ETOH and 2% carbowax) o If induced: inhalation of aerosol solution for 20 mins to produce deep cough sample Quality of sputum samples is determined by the number of epithelial cells and polymorphonuclear (PMN) leukocytes per low power field (LPF) o An acceptable specimen has:  >25 PMN leukocytes / LPF ...