Related Experiment Video
Updated: Aug 14, 2026
08:20
Cell Block Preparation from Cytology Specimen with Predominance of Individually Scattered Cells
Published on: July 21, 2009
The International System for Reporting Serous Fluid Cytopathology: The Need for Version 2.0
Padmini C Vijayasarathy1, Shanmugapriya Shankar2, Anil K Sirasagi2
1Department of Pathology, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India.
Journal of Cytology
|August 13, 2026
Summary
The International System for Reporting Serous Fluid Cytopathology (TIS) effectively categorizes serous effusions, with high malignancy risk in suspicious and atypical categories. Further refinement of atypical cell criteria is recommended for improved diagnostic accuracy.
Area of Science:
- Cytopathology
- Oncology
- Fluid analysis
Background:
- Serous effusion cytopathology requires ancillary tests for malignancy detection.
- The International System for Reporting Serous Fluid Cytopathology (TIS) provides standardized categories: nondiagnostic (ND), negative for malignancy (NFM), atypical cells of undetermined significance (AUS), suspicious for malignancy (SFM), and malignant (MAL).
Purpose of the Study:
- To reclassify serous body fluids using the TIS system.
- To assess the risk of malignancy (ROM) for each TIS category.
Main Methods:
- A retrospective cross-sectional study of 370 serous effusions over 4.5 years.
- Fluids were recategorized according to TIS, and ROM was calculated.
- Analysis of variance (ANOVA) and chi-square tests were used for statistical analysis.
Main Results:
- Ascitic fluid (60.5%) and pleural fluid (36.7%) were the most common effusion types.
- ROM varied significantly across TIS categories: ND (14.28%), NFM (10.82%), AUS (83.33%), SFM (86.66%), and MAL (100.00%).
- A statistically significant P-value of 0.002 was observed.
Conclusions:
- TIS offers a standardized and efficient method for categorizing serous body fluids.
- The similar ROM in AUS and SFM categories suggests a need for refining the criteria for the AUS category to improve diagnostic precision.
Keywords:
1. The International System for Reporting Serous Fluid Cytopathology is a system that has introduced discipline in reporting body fluid cytopathology by using categories like nondiagnostic, negative for malignancy, atypical cells of undetermined significance (AUS), suspicious for malignancy (SFM), and malignant.2. The category AUS has not been frequently used in routine reporting in the past, and this study showed the AUS category to have a very close risk of malignancy to the SFM category.3. There is a requirement for finer refinement of the cytopathological criteria for classifying the cases under the AUS category.Cytologyeffusionsserous fluidsstandardizationthe international system