Guidelines for reporting negative cytology
Negative for intraepithelial lesion or malignancy The Bethesda system links previous categories normal and benign alterations as a single negative category. The EU guidelines support this opinion (Arbyn et al. 2008; Herbert et al. 2007). Benign changes that need not be reported in a negative report Hormonal patterns (post-partum or atrophic) Repair changes Microglandular […]
Potential false positives
Potential false positives Although the clinical implications of false positives seem less significant than false negatives, they cause unnecessary anxiety to patients and may lead to unnecessary excisional treatment, which is now known to increase the risk of premature rupture of membranes in pregnancy. Although the risks are associated with large excisions rather than LLETZ […]
Guidelines for reporting abnormal cytology
While describing the features of the spectrum of squamous and glandular abnormalities seen in cervical cytology and histology it is essential to use terminology that is understood by everyone involved in the screening process and for results to be comparable to those reported in other regions and countries. Much of the world uses the Bethesda […]
Collecting, preparing and fixing the cellular samples
Sources of error A chapter has been dedicated to guidelines for taking a cellular sample, fixing and processing conventional and liquid-based preparations. Here we discuss sources of error during this stage in the process. Clinical condition of the patient at the time of sampling Samples taken during, or in the few days before or after, […]
Cytological screening
The ability to screen a predominantly negative cytology slide and notice occasional abnormalities among many thousands of cells requires specialist training, knowledge of the nature of normal and abnormal cells, and concentration and dedication. Here we deal with sources of error in screening and how they can be avoided. Sources of error Personal reasons […]
Processing the sample in the laboratory
Sources of error Procedures for processing cervical samples are described elsewhere. There are many diagnostic errors that can occur due to poor processing techniques in the laboratory: Clerical procedures for receiving the samples Inconsistencies between information on the request form and sample. Misspelling of name or incorrect date of birth leading to screening history […]
References
Arbyn M, Anttila A, Jordan J et al. (Eds). (2008). European guidelines for quality assurance in cervical cancer screening, second edition. Chapter 3 pp.87-88. European Communities 2008. Available as www.screening.iarc.fr/doc/ND7007ENC_002.pdf Blanks RG, Kelly RS (2010). Comparison of cytology and histology results in English cervical screening laboratories before and after liquid-based cytology conversion: do the data […]
QA and QC of the complete cervical screening process
Protocols for quality control (QC) and quality assurance (QA) A pathology test that screens an entire healthy population to find the few with disease must have clearly defined protocols for QA and QC in order to become an acceptable and viable screening test. The same protocols are required for cytology as a triage test […]
Processing cytology samples in the laboratory
Processing cytology samples involves reception of the specimen and request form, preparation of slides for microscopic examination, staining, screening and reporting the slides. All these processes are subject to quality control and quality assurance measures. Reception of specimen and request form Details on specimen and form are checked to make sure they match. Specimen […]
References
Arbyn M, Herbert A, Schenck U et al. European guidelines for quality assurance in cervical cancer screening: recommendations for collecting samples for conventional and liquid-based cytology. Cytopathology 2007;18:133-9. Arbyn M, Bergeron C, Klinkhamer P et al. Liquid compared with conventional cervical cytology: a systemic review and meta-analysis. Obstet Gynecol 2008;111:167-77. Davey E, Barratt A, Irwig […]