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Cell Block Preparation from Cytology Specimen with Predominance of Individually Scattered Cells
Published on: July 21, 2009
Sodium Alginate and Plasma Thrombin Methods of Cell Block Preparation in Body Fluid Cytology: A Comparative Study
Amrutha Anitha Ponnamkottu1, Debasis Gochhait1, Rashmi P Joshi1
1Department of Pathology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, Puducherry, India.
Insights
Sodium alginate (SA) cell blocks offer a cost-effective alternative to plasma thrombin (PT) for effusion fluid cytology. While SA shows comparable cellularity and cytomorphology, it presents artefacts, yet remains suitable for diagnosis and immunohistochemistry (IHC).
Area of Science:
- Cytopathology
- Histopathology
- Biomaterial Science
Background:
- Cytology laboratories process numerous effusion fluid samples, making cell block preparation with immunohistochemistry (IHC) essential.
- The standard plasma thrombin (PT) method for cell block preparation is costly, necessitating a more economical alternative.
- This study evaluates sodium alginate (SA) as a potential cost-effective substitute for PT in effusion cytology.
Purpose of the Study:
- To compare the efficacy of sodium alginate (SA) and plasma thrombin (PT) methods for effusion cell block preparation.
- To assess the agreement between SA and PT methods regarding cellularity, cytomorphology, and artefact presence.
- To determine the feasibility of using SA cell blocks for immunohistochemistry (IHC) and routine cytology diagnostics.
Main Methods:
- Seventy-six effusion fluid samples were analyzed.
- Cell blocks were prepared using both the routine PT method and the SA method.
- Haematoxylin and Eosin stained sections were blindly evaluated by two cytopathologists for cellularity, cytomorphology, and artefacts.
Main Results:
- Both SA and PT methods demonstrated comparable performance in terms of cellularity and cytomorphology.
- Satisfactory cellularity was achieved in 96.0% of SA cases versus 93.4% of PT cases.
- While SA blocks showed a gel-like artefact, it did not impede diagnosis, and IHC staining yielded excellent results.
Conclusions:
- Sodium alginate (SA) cell blocks are a viable and cost-effective alternative to plasma thrombin (PT) for effusion cytology.
- SA method provides comparable diagnostic quality to PT, with artefacts not affecting diagnostic interpretation.
- SA cell blocks are suitable for immunohistochemistry (IHC) and routine cytology, especially in resource-limited settings.
Background:
Cytology laboratories handle a substantial number of effusion fluid samples, and preparation of cell block with immunohistochemistry (IHC) has become an integral part. The routinely used plasma thrombin (PT) method is expensive, and a cost-effective alternative is the need of the hour. This study aimed to find the level of agreement between the sodium alginate (SA) and PT methods for cellularity, cytomorphology, and artefacts.
Methodology:
A total of 76 samples received in the cytology laboratory were evaluated. The cell blocks were prepared using the PT (routine) and SA methods from the cell sediment. Haematoxylin and Eosin sections from cell blocks were evaluated. Two cytopathologists scored the quality in a blind fashion by assessing cellularity, cytomorphology, and artefacts.
Results:
The study showed comparable performance between the two methods in terms of cellularity and cytomorphology. Satisfactory cellularity was observed in 93.4% of cases with PT and 96.0% with SA, while well-preserved cytomorphology was noted in 84.2% and 72.3% of cases, respectively. However, a notable difference was seen in the background of the SA cell block section in the form of a gel-like artefact. A few IHC markers were attempted only on the SA cell block, and the results were excellent.
Conclusions:
Overall, the two techniques performed similarly. However, artefacts were present in the SA method, which did not affect the diagnosis. IHC was feasible and diagnostically interpretable on SA cell blocks. For routine cytology diagnostics, sodium alginate cell blocks can be a viable alternative to plasma thrombin cell blocks in resource-poor settings.
