EXFOLIATIVE CYTOLOGY

• Exfoliative cytology


  Microscopic examination of cells that have been desquamated from epithelial surfaces, spontaneously shed or physically removed from epithelial & mucous membranes

  
• Diagnostic cytology


  Microscopic examination of cells from different body sites for diagnostic purposes

  
• Uses of exfoliative cytology


  • Detection of malignant cells in body fluids
  • Detection of premalignant cervical lesions in women (e.g. Pap smear)
  • Assessment of female hormonal status in case of sterility / endocrine disorders
  • Determination of genetic sex (Barr body)
  • Detection of infectious agents

  
• Specimens for exfoliative cytology


  • Cervicovaginal smear (Pap smear)
  • Nipple discharge
  • Gastric or bronchial secretions
  • Pleural and peritoneal fluids
  • Sputum
  • Urine Sediment
  • Cerebrospinal Fluid Specimens (CSF)

  
• Smear preparation


  1. Smears should be freshly prepared

  2. Direct smear preparation done evenly on a clean slide

  3. Patient's identity and type of specimen should be indicated on the request form

  4. Laboratory identifying number should be put on the slide (frosted-end slide)
• Fixation


  1. Immediate fixation by quick immersion in fixative solution or by spray necessary to secure optimal specimen

  2. If specimen > few drops, centrifuge fluid 1st at moderate speed (2000 RPM) for 2 minutes, decant supernatant fluid, smear the sediment directly onto the slide or cytocentrifuge (cytospin) on the coated slides with a thin film of egg albumin

  3. Minimum fixation time varies, some smears can be fixed in 10 minutes with 90% alcohol, smears may be left in alcohol-based fixative for weeks months before staining
• Commonly used fixatives for cytologic smears


  • Equal parts of 95% ethyl alcohol and ether
  • 95% ethyl alcohol
• Precautions observed during fixation: 1) ID the slides before preparing the smears, 2) Attach a paper clip to the identified end of the slide before preparing the smear, 3) Smears should be placed into the fixative container immediately after preparation, 4) Place each smear in fixative by a single uninterrupted motion to avoid rippling of smeared material, 5) Avoid striking the bottom of the fixing container forcefully to prevent dislodging the material from the slide
• Have the fixative bottle open before preparing the smears. If spray fixative is used, slide should be kept in a distance approx. 12 inches away.
• Anaplasia


  • Lack of differentiation
  • Pleomorphism - variation in size and shape of cells and nuclei
  • Abnormal nuclear morphology - hyperchromatism, nuclei disproportionately large
  • Mitoses
  • Loss of polarity - cells grow in anarchic or disorganized fashion
  • Presence of bizarre cells, necrosis
• Normal N:C ratio is 1:4 or 1:6
• Transformation Zone (T-Zone)


  Junction of the endocervical / ectocervical mucosa where majority of cervical carcinomas & precancerous lesions of the cervix arise

  
• Cytologic collection and preparation for conventional Pap smears


  1. Endocervical brush - samples of endocervical canal

  2. Vaginal scrape - for patients with hysterectomy

  3. Lateral vaginal scrape - used for hormonal evaluation

  4. Four quadrant vaginal scrape - for localization of vaginal adenosis

  5. Vulvar scrape - for detection of herpetic lesions or carcinoma

  
• Papanicolau method (Pap smear)


  Standard staining for exfoliative cytology, provides transparent blue staining of cytoplasm, excellent nuclear detail, and predictable color range for identification and classification of cells

  
• Modified Papanicolau staining


  1. Stain conventional Pap smears by routine Pap staining procedure

  2. Use an automated stainer for smears prepared with liquid-based technique

  3. Avoid contamination by staining non-gyne & FNA specimens separately, staining suspicious cases separately, assessing cellularity of fluids & FNA specimens and staining those with high potential for cross contamination separately, changing all stains weekly or as needed, discarding first rinsing alcohol daily and advancing subsequent rinses, keeping smears from drying in between any of the staining steps, keeping a record of changes in staining procedure, identifying and correcting all problems with staining
• Vaginal hormone cytology


  Relatively inexpensive, can be performed regularly even for pregnant women, upper lateral 1/3 of the vaginal wall is more accessible and less likely to be contaminated, LPO assesses quality of smear & staining, HPO provides quantitative assessment
• Vaginal epithelial cells


  • Mature Superficial Cells (↑Estrogen)
  • Intermediate Cells (↑Progesterone)
  • Parabasal Cells
• Navicular cells


  Boat-shaped intermediate cells which fold or curl on edges, combined Estrogen-Progesterone effect, found in latter half of menstrual cycle, during pregnancy, menopause
• Pregnancy cells


  Round, oval or boat-shaped cells with translucent basophilic cytoplasm greatest at the center, deeper blue stain of the cytoplasm at the periphery

  
• Endometrial cells


  Small cells, slightly cylindrical with less basophilic cytoplasm, tightly packed groups of 3, shed in response to ovarian hormones during 1st-10th days following menstruation
• Endocervical glandular cells


  Occur in large groups or small sheets, pale blue/gray cytoplasm, finely vacuolated, nuclei with finely granular chromatin, honeycomb appearance when viewed on end

  
• Normal Pap smear shows benign squamous cells

  
• Abnormal Pap smear shows abnormal cells

  
• ns


  Not specified
• ff


  Not specified
• menopause


  Not specified
• Other cells


  • Navicular cells: boat-shaped intermediate cells that fold or curl on edges
  • Pregnancy cells: round, oval or boat-shaped cells with translucent basophilic cytoplasm greatest at the center, deeper blue stain of the cytoplasm at the periphery
  • Endometrial cells: small, slightly cylindrical cells with less basophilic cytoplasm, tightly packed groups of 3, shed in response to ovarian hormones
  • Endocervical glandular cells: occur in large groups or small sheets, pale blue/gray cytoplasm, finely vacuolated nuclei, honeycomb appearance when viewed on end
• Benign squamous cells are seen in a normal Pap smear

  
• HPV and mild dysplasia are seen in an abnormal Pap smear
• Squamous cell carcinoma can be seen on a Pap smear
• Adenocarcinoma can be seen on a Pap smear
• Barr body can be seen on a Pap smear
• Monilia can be seen on a Pap smear
• Clue cells can be seen on Pap smears of patients with bacterial vaginosis

  
• Trichomonas vaginalis can be seen on a Pap smear
• Respiratory tract specimens


  • Obtained to exclude possibility of malignancy or infectious agents
  • Types: sputum, bronchoalveolar lavage/bronchial washing, bronchial brushing
• Sputum collection


  1. Obtain at least 3 consecutive AM sputum specimens

  2. Collect early AM sputum by deep cough in wide-mouthed jar containing Saccomanno fluid

  3. Induced sputum collected using inhalation of aerosol solution

  4. Minimum 2-4 slides for extensive study, 1 air dried for Giemsa staining, at least 2 for Pap staining
• Sputum collected should have been coughed from "down-deep" to ensure it represents sputum and not saliva
• Mucus present preserves cell constituents, but specimen should be as fresh as possible for better cellular detail

  
• Bronchial brushing


  1. Specimen directly smeared onto 2 labeled slides, pull technique, slides fixed (spray or immersed in 95% alcohol)

  2. Failure to fix specimen ASAP leads to air drying artifacts