Cytopathology vs Histopathology CAT: OmpathStudy

--- SECTION A: MDPA 3511 CAT — Short Answer Questions Q1. Define the following terms: a. Cytopathology — The study of disease at the cellular level, examining individual cells (exfoliated, aspirated, or brushed) rather than intact tissue architecture, to diagnose disease. b. Histopathology — The microscopic study of diseased tissue, examining tissue architecture and cellular detail in sections cut from biopsy/surgical specimens. c. Laboratory Request Form — A standardized document accompanying a specimen to the laboratory, providing patient/clinical details and the specific test(s) requested. d. Tissue Fixation — The process of treating tissue with a chemical agent (e.g., formalin) to preserve cellular/tissue structure, prevent autolysis and putrefaction, and stabilize the specimen for processing. e. Tissue Decalcification — The process of removing calcium salts from bone or heavily calcified tissue using acids or chelating agents, so the tissue can be sectioned thinly for microscopy. f. Fine Needle Aspiration (FNA) — A minimally invasive technique using a fine-gauge needle and syringe to aspirate cells/fluid from a palpable mass for cytological examination. g. Aspiration Cytology — Cytological study of cells obtained by aspiration (via FNA) from a solid mass or fluid collection. h. Exfoliative Cytology — Study of cells that have spontaneously shed (exfoliated) or been scraped/brushed from epithelial surfaces (e.g., Pap smear, sputum cytology). i. Immunohistochemistry — A technique using labelled antibodies to detect specific antigens/proteins within tissue sections, aiding diagnosis, classification, and prognostication of tumours. j. Frozen Section — A rapid tissue preparation technique where tissue is snap-frozen and sectioned (rather than formalin-fixed and paraffin-embedded), used for intraoperative diagnosis within minutes. --- Q2. Mr Mtafiti Bora's father — the Medical Officer-Intern was filling a document to accompany a specimen to the lab. a. Name of the document: Laboratory (Histopathology/Cytology) Request Form. b. Purpose: To formally request laboratory analysis of the specimen, ensure correct patient identification, provide clinical context needed for accurate interpretation, and create a documented chain of custody/traceability. c. Information required when filling the document: Patient's full name, age/DOB, sex, hospital/ID number Ward/clinic and requesting clinician's name and contact Date and time of specimen collection Type and site/source of specimen Relevant clinical history and provisional diagnosis Specific investigation(s) requested Previous relevant results/biopsy numbers (if any) Signature of the person collecting/requesting --- Q3. The specimen was put in fixative. a. What is a fixative? A chemical agent (or physical method) used to preserve tissue/cellular structure and prevent degradation after removal from the body. b. Functions of a fixative: Prevents autolysis (enzymatic self-digestion) and bacterial putrefaction Preserves and stabilizes tissue architecture and cellular detail Hardens tissue to facilitate sectioning Inactivates infectious agents Preserves antigenicity (important for IHC) and allows staining c. Most commonly used fixative: 10% neutral buffered formalin (formaldehyde solution). d. Other examples of fixatives: Glutaraldehyde, absolute ethanol, methanol, Bouin's solution, Zenker's solution, acetone, mercuric chloride-based fixatives (e.g., B5), paraformaldehyde. --- Q4. A specimen needed to undergo decalcification. a. What is tissue decalcification? The process of removing calcium salts from bone/calcified tissue after fixation, using acids or chelating agents, so the hardened tissue becomes soft enough to be cut into thin sections for histological examination. b. Examples of tissue requiring decalcification: Bone biopsies/resections, teeth, calcified tumours (e.g., osteosarcoma specimens), heavily calcified arteries, calcified lymph nodes, some breast biopsies with microcalcifications. c. Examples of chemical decalcifying agents: Nitric acid, formic acid, hydrochloric acid, EDTA (ethylenediaminetetraacetic acid — a chelating agent, slower but gentler). --- Q5. Signage read "Cytopathology." a. Two branches of cytopathology: Exfoliative cytology — examines cells that have naturally shed or been scraped from epithelial surfaces Aspiration (interventional) cytology — examines cells obtained by needle aspiration from solid masses or fluid collections b. Examples for each branch: Exfoliative: Pap (cervical) smear, sputum cytology, urine cytology, pleural/peritoneal fluid cytology Aspiration: Fine needle aspiration of thyroid nodule, breast lump, lymph node, or salivary gland mass --- Q6. Miss Maisha Bora, positive HPV 16, mother advised follow-up cervical smear. a. Name of the test: Papanicolaou (Pap) smear/test. b. Fixative used on cervical smear sample: 95% ethanol (wet fixation), applied immediately after smearing onto the slide. c. Condition(s) screened for: Cervica