Tips for Best Practice on Unsatisfactory Cytology

Post date: November 15, 2024
Reviewed by: Erin L. Nelson, MD

An unsatisfactory cytology result is reported when there are insufficient cells for the cytopathologist to properly evaluate the specimen. This occurs in approximately 2% of cytologic samples. A number of factors can contribute to this outcome, including atrophy, poor or improper collection technique, obscuring inflammation, poor slide preparation, presence of blood, excessive lubricant in the specimen, and increased thickness of the smear. 

When specimen results are reported as unsatisfactory, the 2019 management guidelines recommend repeating age-based screening in 2-4 months (Figure 1). A negative HPV test obtained in conjunction with unsatisfactory cytology should not be considered a valid result. In this scenario, the recommendation is to repeat both the cytology and HPV test in 2-4 months. Colposcopy should be performed if the subsequent cytology result is again unsatisfactory.

Overall, these recommendations are unchanged from the 2012 management guidelines. 

Figure 1. Management of unsatisfactory cytology (adapted from Figure 5 of Perkins et al, 2019 ASCCP Risk-Based Management Consensus Guidelines for Abnormal Cervical Cancer Screening Tests and Cancer Precursors).

This topic will likely become increasingly less relevant with more widespread adoption of primary HPV testing over time.

Standard Abbreviations

HPV - Human Papillomavirus
hrHPV - High-Risk Human Papillomavirus
HSIL - High-Grade Squamous Intraepithelial Lesion
VaIN - Vaginal Intraepithelial Neoplasia
NCCN - National Comprehensive Cancer Network
LSIL - Low-Grade Squamous Intraepithelial Lesion
NILM - Negative for Intraepithelial Lesion or Malignancy
ASC-H - Atypical Squamous Cells, Cannot Rule Out High-Grade Lesion
ASC-US - Atypical Squamous Cells of Undetermined Significance
AGC - Atypical Glandular Cells
AIS - Adenocarcinoma In Situ
LEEP - Loop Electrosurgical Excision Procedure
ECC - Endocervical Curettage
CIN - Cervical Intraepithelial Neoplasia
SCJ - Squamocolumnar Junction
mRNA - Messenger Ribonucleic Acid
CO2 - Carbon Dioxide
WHO - World Health Organization

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