Journal List > Korean J Cytopathol > v.19(2) > 1006539

Korean J Cytopathol. 2008 Sep;19(2):86-98. Korean.
Published online September 30, 2008.
Copyright © 2008 The Korean Society for Cytopathology
Cytologic Findings of Cerebrospinal Fluid
So-Young Jin, M.D.
Department of Pathology, Soonchunhyang University Hospital, Seoul, Korea.
Received August 13, 2008; Accepted August 25, 2008.


Cerebrospinal fluid (CSF) cytology is based on the cytopathologic findings of other body fluids. However, CSF's cytologic features are less familiar to physicians than are those of the other body fluid's cytology because of the small number of cases. The low overall diagnostic accuracy and the presence of false positivity still remain as problems. The incidence of lymphoreticular malignancies and metastatic carcinomas are rather higher than that of primary brain tumors. In this review, the characteristic cytologic findings of conventional CSF cytology are reviewed along with a brief note on the technical preparation and diagnostic pitfalls.

Keywords: Cerebrospinal fluid; Cytology; Diagnostic pitfalls


Fig. 1
Normal cells of cerebrospinal fluid. Few lymphocytes and a monocyte are seen (Papanicolaou stain).
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Fig. 2
Astrocytes as normal contaminants. Three microfragments of glial tissue are found in the ventricular fluid obtained during operation (Papanicolaou stain).
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Fig. 3
Meningitis. The cell components consist of heterogenous mixed population of small and large lymphocytes, histiocytes, and polymorphous leukocytes in viral(A) and tuberculous(B) meningitis. (Papanicolaou stain).
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Fig. 4
Cryptococcosis. A few round fungal organisms with thick mucous capsule are noted in the inflammatory background. (A&B Papanicolaou stain).
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Fig. 5
Glioblastoma multiforme. Many single cells and clusters of large atypical cells are present with fragment of fibrillary astrocytic differentiation (Papanicolaou stain).
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Fig. 6
Medulloblastoma. A few single cells (A) or a small cluster (B) of small round cells with hyperchromatic nuclei and small amount of cytoplasm can be found (Papanicolaou stain).
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Fig. 7
Acute leukemia. Dispersed monotonous population of small lymphoblasts(A) and myeloblasts(B) demonstrate nuclear protrusion or indentation with some hand-mirror cells(C). Air dried smear highlights nuclear features of acute leukemia(D). (A-C: Papanicolaou stain D: Giemsa).
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Fig. 8
Malignant lymphoma. Monotonous small atypical lymphoid cells are scattered with similar nuclear features of leukemic cells such as papillary protrusion or indentation(A). Large atypical cells with prominent nucleoli are dispersed with occasional mitotic figures(B). (Papanicloaou stain).
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Fig. 9
Breast cancer. A number of single cells and clusters or cords of small and large atypical cells with prominent nucleoli are noted, consistent with ductal carcinoma(A). Few small round tumor cells with intracytoplasmic lumen are seen, consistent with lobular carcinoma(B). (Papanicloaou stain).
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Fig. 10
Squamous cell carcinoma of lung. Ovoid to spindle tumor cells with occasional pyknotic nuclei are present in the background of tumor diathesis (A). Rounded tumor cells with distinct intercellular junction are found (B). (Papanicolaou stain).
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Fig. 11
Adenocarcinoma of lung. A few large clusters of adenocarcinoma cells demonstrate intracytoplasmic vacuoles and occasional acinar arrangement(A). Bronchioloalveolar carcinoma cells show a paillary cluster of bland looking tumor cells with characteristic hobnail appearance(B). (Papanicolaou stain).
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Fig. 12
Small cell carcinoma of lung. Small hyperchromatic tumor cells having hyperchromatic nucleus, scanty rim of cytoplasm, and indistinct nucleoli exhibit short cords with characteristic nuclear molding. (A&B, Papanicolaou stain).
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Fig. 13
Stomach cancer. A number of atypical tumor cells and three dimensional clusters with some intracytoplasmic mucin vacuoles are found, accompanied by innumerable starch granules(A). Note small size of tumor cells(B) and bland looking signet ring cells(C). (Papanicolaou stain).
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Table 1
Cytomorphologic Findings in Different Types of Metastatic Nonlymphoreticular Neoplasm
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