- Diagnosing Tumor/Abscess/Cyst/Boils/Edema/Haematoma/ lumps and bumps
- cutaneous and subcutaneous lesions are the most commonly sampled for cytological evaluation
- collection of cytologic specimens (prepare the site for sample collection, Do FNAB, rotate needle to get sample, draw negative pressure, pull out plunger and eject specimen with pressure on slide, make slide and do staining)
- Staining- Romanowsky type stains (Wright’s, Giemsa, Diff-Quik)
- NC Ratio: The nuclear/cytoplasmic (N/C) ratio should range from 1/3 to 1/10, depending on the tissue type. and exception to this is the lymphocyte, which normally has an N/C ratio of 1/1.
- The following checklist includes features that can be examined to determine tissue type and likely behavior of the lesion: 1) cell numbers, 2) cell distribution within the smear, 3) cell shape, 4) nucleus:cytoplasm ratio, 5) pleomorphism (both nuclear and cytoplasmic), 6) number, shape, and size of nucleoli, and 7) cytoplasmic content such as melanin, metachromatic granules, fat, etc. Classification of the cell type and likely behavior may require a tissue biopsy. With few exceptions, histology will be necessary for a definitive diagnosis and is always necessary to assess mitotic index and to grade a tumor.
- Even if a definitive cytological diagnosis cannot be made, cytological findings may be of value in determining which additional diagnostic laboratory tests may be of further value (e.g., histopathology or culture) or directing further investigative procedures such as ultrasonography or radiography (e.g., when skin lesions may be involving bone or joints).
- Neoplasia (Benign or Malignant) and Dysplasia:
- Normal cells react to their environment and to many pathologic processes by degenerating, repairing, and by reacting to chronic irritants. These processes lead to dysplasia, in which certain nuclear and cytoplasmic characteristics can resemble neoplasia. It is usually possible to differentiate neoplastic from dysplastic processes in cells exfoliated from a solid tissue, since one has a clinical history, radiographs, and the presence of a mass to suggest that a neoplasm is present. In dysplasia, there is often a history of a chronic irritant or infection, and the presence of inflammatory cells along with the suspicious cell population makes one unwilling to diagnose a tumor without a histopathologic biopsy.
- However, disparity in nucleolar size and shape within the same cell, or variation in the number of nucleoli in cells within the same tissue fragment strongly suggests malignancy.
- Irregularity of the nuclear membrane is an abnormality which is generally not seen in benign or dysplastic cells, and as such is a strong indicator of malignancy.