Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2025 Jun 17:1-12.
doi: 10.1159/000546947. Online ahead of print.

Not Enough Cells: How Insufficient Cytological Specimens Are Mirrored by Reporting Systems - Journey from the Bethesda to the WHO Reporting Systems

Ivana Kholová  1   2   3   4
Affiliations
Review

Not Enough Cells: How Insufficient Cytological Specimens Are Mirrored by Reporting Systems - Journey from the Bethesda to the WHO Reporting Systems

Ivana Kholová. Acta Cytol. .

Abstract

Background: Pap classes have been replaced by organ-specific reporting systems in recent decades; however, part of the cytological specimens is insufficient. The present review summarizes how different organ-specific systems define the insufficient category: both quantitative and qualitative criteria are used. In addition, the sample volume may be evaluated in certain specimens.

Summary: The reasons for an insufficient sample may vary and depend either on the lesion itself or the sampling procedure.

Key messages: The management recommendations for insufficient specimens improve communication between cytopathologists and treating physicians.

Keywords: Cytology; Fine-needle aspirate biopsies; Insufficient specimens; WHO reporting systems for cytopathology.

PubMed Disclaimer

Conflict of interest statement

The author was a member of the journal’s editorial board at the time of submission. The author has no other conflicts of interest to declare.

Figures

Fig. 1.
Fig. 1.
Fishbone diagram of the most common causes of insufficient cytologic samples.
Fig. 2.
Fig. 2.
An example of a diagnostic thyroid sample. A diagnostic thyroid sample is defined as containing at least 6 groups of 10 well-preserved and well-stained follicular cells, according to the Bethesda System for Reporting Thyroid Cytopathology. Papanicolaou stain. Original magnification ×200.
Fig. 3.
Fig. 3.
Only one preserved group of 11 follicular cells was present. A thyroid gland specimen with less than 6 groups of 10 well-preserved and well-stained follicular cells is placed into the nondiagnostic/unsatisfactory category according to the Bethesda System for Reporting Thyroid Cytopathology. Papanicolaou stain. Original magnification ×200.
Fig. 4.
Fig. 4.
A thick bloody background causes follicular cells to be fully obscured. The specimen is categorized as nondiagnostic/unsatisfactory according to the Bethesda System for Reporting Thyroid Cytopathology. Papanicolaou stain. Original magnification ×200.
Fig. 5.
Fig. 5.
Thyroid specimen with red blood cells, macrophages and siderophages represents cyst fluid material categorized as nondiagnostic/unsatisfactory according to the Bethesda System for Reporting Thyroid Cytopathology. Papanicolaou stain. Original magnification ×200.
Fig. 6.
Fig. 6.
The presence of atypical urothelial cells in a urinary sample lead to a categorization other than nondiagnostic according to the Paris System for Reporting Urinary Cytology. Papanicolaou stain. Original magnification ×200.
Fig. 7.
Fig. 7.
Sparse specimen with atypical squamous cells. Despite the low number of cells, it will not lead to a nondiagnostic categorization according to the Paris System for Reporting Urinary Cytology. Papanicolaou stain. Original magnification ×200.
Fig. 8.
Fig. 8.
Acellular sample from the parotid gland fulfills the Milan System for Reporting Salivary Gland Cytopathology criterion of “rare or absent cells with threshold of 60 lesional cells”. Papanicolaou stain. Original magnification ×200.
Fig. 9.
Fig. 9.
A necrotic noncellular debris specimen from the parotid gland is categorized as nondiagnostic according to the Milan System for Reporting Salivary Gland Cytopathology. Papanicolaou stain. Original magnification ×200.
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Mezei T. Current classification systems and standardized terminology in cytopathology. Rom J Morphol Embryol. 2020;61(3):655–63. - PMC - PubMed
    1. Kurman RJ, Solomon D, editors. The Bethesda System for Reporting Cervical/Vaginal Cytologic Diagnoses. Definitions, criteria, and explanatory notes for terminology and specimen adequacy. New York: Springer; 1994.
    1. Solomon D, Nayar R, editors. The Bethesda System for Reporting Cervical Cytology. Definitions, criteria, and explanatory notes. New York: Springer; 2004.
    1. Nayar R, Wilbur D, editors. The Bethesda System for reporting cervical cytology. 3rd ed. New York: Springer; 2015. p. 1–313.
    1. Ali SZ, Cibas E, editors. The Bethesda System for reporting thyroid cytopathology. 1st ed. New York: Springer; 2010.