Is there a right time for cyto/histo correlation in gyn cytology?
Andrew A. Renshaw, MD
Cytologic-histologic correlation is an important component of any
quality improvement program in cytology. A documented effort must
be made to obtain and review follow-up histologic reports or material
that is available within the laboratory when high-grade squamous
intraepithelial lesion or malignant findings are identified in gynecologic
cytology.1 There is no specific requirement to obtain
correlation for any gynecologic cytology specimen in the absence
of HSIL, and there is no specific requirement that histologic findings
be correlated with cytologic findings, though many laboratories
do make these correlations and the results certainly can be a component
of a quality improvement program.2-5
The time period
over which these correlations should be made is not specified. Data
do suggest, however, that the optimal period for examination may
be 60 to 100 days. In a study involving 419 low-grade squamous intraepithelial
lesion and 277 HSIL smears, Renshaw, et al.6 correlated
the rate of subsequent biopsy and the rate of correlation with that
biopsy over a period of one year. In this study, 811 biopsies were
performed. While biopsies that correlated with the initial cytologic
finding could be identified as late as one year after the initial
cytology, the highest rate of confirmation was obtained in biopsies
performed within 60 days, and fully 78 percent of all correlating
biopsies were obtained within the first 100 days. The chance of
finding a correlating smear decreased after that time. In other
words, biopsies performed more than 100 days after the initial biopsy
were less likely to correlate with the initial cytologic finding.
for the increased number of discrepancies was regression of the
lesions. After 100 days, there is a greater likelihood of regression,
which leads to an increase in the number of perceived “false-positive”
cytology results when, in fact, a number of them are actually true
positives. Limiting correlations to 100 days after the cytologic
specimen was obtained is a reasonable way to limit the impact of
“false-positive” correlations on the quality improvement
program and the cytologic staff, while at the same time obtaining
the majority of all biopsies for which correlation is available.
is whether cytologic specimens should be taken at the same time
as the biopsy and correlated with it. Some literature suggests that
cytologic specimens taken at that time have a higher likelihood
of being false-negatives—that is, the cytologic specimen is
more likely to not sample the lesion found in the biopsy.7
In the study by Renshaw, et al.,6 this was not found
to be the case, and indeed cytologic specimens obtained at the time
of biopsy were more likely to correlate with the results of biopsy
than cytologic specimens taken at any subsequent time.
specifies that concurrent Pap tests need to be correlated with the
biopsy since these cytology specimens were not the reason for obtaining
the biopsy. Technically concurrent biopsies are not a followup to
the cytology. In the interests of patient care, however, HSIL or
malignancy identified on the cytology specimen with a concurrent
negative or low-grade biopsy result should be reconciled. Furthermore,
the subsequent histologic specimens must be correlated. It appears
that the optimal biopsies to correlate are those obtained within
60 to 100 days after the Pap test.
of American Pathologists. Laboratory Accreditation Program. Cytopathology
checklist, Nov. 22, 2002. Question CYP.07543.
- Joste NE,
Crum CP, Cibas ES. Cytologic/histologic correlation for quality
control in cervicovaginal cytology. Am J Clin Pathol. 1995;103:32-34.
- Tritz DM,
Weeks JA, Spires SE, et al. Etiologies for non-correlating cervical
cytologies and biopsies. Am J Clin Pathol. 1995; 103:594-597.
- Jones BA,
Novis DA. Cervical Biopsy-Cytology Correlation. Arch Pathol
Lab Med. 1996;120:523-531.
- Wright TC,
Cox JT, Massad LS, et al. 2001 consensus guidelines for the management
of women with cervical cytological abnormalities. JAMA. 2002;287:
A, Granter SR. Appropriate follow-up interval for biopsy confirmation
of squamous intraepithelial lesions diagnosed on cervical smear
cytology. Am J Clin Pathol. 1997;108:275-279.
WM. An approach to the problem of false negatives in gynecologic
cytologic screening. Acta Cytol. 1989;33: 814-818.