Introduction to Histopathology and Cytology

Practice flashcards covering definitions, specimen types, laboratory components, and workflow for Histopathology and Cytology based on the UTAS-SOMS lecture.

Histopathology

A branch of pathology originating from the Greek words histos (tissue), pathos (disease), and logos (study), which deals with the scientific study of disease in tissue sections.

Cytology (Cytopathology)

The branch of science that studies the structure, function, and pathology of individual cells to diagnose or screen for diseases such as cancer, infections, and inflammatory conditions.

Whole mount

A histological preparation involving an entire specimen, such as a fungus or parasite, that should be no more than $0.2-0.5\,mm$ in thickness.

Sections

The most common histological preparation where tissue is cut into $3-5\,mm$ pieces, processed, and then cut into $5\,\text{microns}$ thick slices using a microtome.

Microtome

A specialized laboratory instrument equipped with an automatic mechanism used for cutting very thin tissue sections.

Smears

Preparations made from fluids like blood, bone marrow, pleural, or ascitic fluid, or by crushing soft tissue between two slides, which are immediately fixed in alcohol.

Impression smear

A preparation created by pressing a clean slide against the moist surface of a tissue to imprint cells for cytological examination.

Biopsy

The removal of a small piece of lesion or tumor from living tissue for diagnosis or to establish the cause of a disease before final removal.

Excisional biopsy

A biopsy method where the entire tumor and the surrounding normal tissue margin are completely removed, often used for skin, breast, and GIT tumors.

Incisional biopsy

A biopsy method used when a tissue mass is too large for complete removal, where only a representative small portion is taken.

Needle biopsy (Fine Needle Aspiration)

A method used for suspicious mass growths not easily accessible, such as deep growths in the breast, lungs, kidney, and liver.

Autopsy

Tissue obtained from a dead body to study or diagnose the cause of death for the advancement of knowledge.

Hot air oven

Laboratory equipment used for the impregnation of histological sections.

Wax dispenser

Equipment used for embedding tissue sections into wax.

Cryostat

A specific laboratory instrument used to cut frozen tissue sections.

Centrifuge

A machine with a rapidly rotating container that applies centrifugal force to separate fluids of different densities.

Safety cabinet

An enclosed, ventilated laboratory workspace designed for safely working with materials contaminated with pathogens requiring a defined biosafety level.

Ware

A general term for glass and plastic laboratory materials, including tissue boxes, molds, bottles, and specimen containers.

Specimen accessioning

The critical laboratory process of receiving, identifying, logging, and labeling incoming patient specimens.

LIMS

Acronym for Laboratory Information Management System, used to assign a unique ID to each specimen for tracking, pathology reporting, and billing.

Accession number

A unique number assigned to a specimen on arrival, followed by the year of entry, which tracks the specimen through processing, reporting, and filing.

Grossing

The process of describing a specimen and placing representative parts into a small plastic cassette for laboratory processing.

Tissue cassettes

Small plastic containers that hold tissue while it is being processed in the histopathology laboratory.