Self Instructional Manual for Cancer Registrars - SEER - National ...

CYTOLOGIC
EXAMINATION
The study of cells, their origin, structure, function, and pathology is called cytology. Cells are
continually shed (exfoliated) from tissues that line the cavities and hollow organs of the body. These
exfoliated cells may float in the fluid and mucous material which bathes or passes through these
cavities. These cells can be examined microscopically to determine their tissue of origin and whether
or not they are malignant. The term exfoliative cytology refers to "microscopic examination of cells
contained within body fluids."
The three body cavities, the pleura (enclosing the lungs), the peritoneum (enclosing the intestinal
tract), and the pericardium (enclosing the heart), may be checked for fluid. The normal fluids within
the body cavities are limited to an insignificant lubricating layer that cannot be aspirated. Therefore,
fluid in any body cavity which can be aspirated indicates a pathological process, commonly malignant
and metastatic. It is believed that the formation of aseites (fluid in the abdominal cavity), for
example, is brought about by colonies of cancer cells which damage the capillaries and lymphatics
resulting in leakage of cancer ceils and plasma directly into the abdominal cavity.
The table below lists the sources of some of the specimens that are examined histologically and
some that are examined cytologically. As a further guide, histology is the study of tissues, while
cytology is the study of cells.
Histolo_ic Examination
Cytologic Examinations
Biopsy material Sputum Bronchial washing
Frozen section Breast Secretion Prostate secretion
Bone marrow biopsy/aspiration (tissue) Gastric fluid Spinal fluid
Operative specimen Peritoneal fluid Urinary sediment
Autopsy specimen Pleural fluid Cervical & vaginal
smears
Bone man'ow
aspiration (cells) Tracheal washing
Bronchial brushing
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