The Value of a Repeat Cytology at the Time of First Colposcopy: A Retrospective Analysis of 1087 Cases.
Jordan M Hall, Jasmine J Han, Oluwole Fadare. MAMC, Tacoma, WA; WRAMC, Washington, DC; Vanderbilt Univ, Nashville, TN
Background: After a referral for an "abnormal" Pap test interpretation, performing a repeat Pap test at the time of colposcopy is not an uncommon practice, although the validity and clinical usefulness of this practice is unclear. In this large scale retrospective study, we assess the value of repeat cytology in this context.
Design: We reviewed the records for 1087 consecutive patients with abnormal Pap tests (i.e. interpretations of ASC-US and above: “referral cytology”) that was followed (within 12 months of the referral) by a colposcopic examination in which both a Pap test (“repeat cytology”) and histological evaluation (i.e. biopsy or ECC) were performed. Repeat cytology was considered “clinically useful” if the results could conceivably have impacted the decision to proceed with or defer a more invasive diagnostic/therapeutic evaluation, such as the performance of a loop electrosurgical excision procedure (LEEP), based on current ASCCP guidelines (e.g LSIL referral cytology followed by HSIL repeat cytology and a CIN 1/negative biopsy, a scenario that may prompt consideration of a LEEP. All cases were further categorized into risk groups: “Low risk (LR)” cytology included the following diagnostic categories: NILM, ASC-US, and LSIL; “Intermediate risk” included LSIL-H and ASC-H, and “High risk (HR)” included HSIL, atypical glandular cells, and carcinoma.
Results: The overall agreement between referral and repeat cytology was 86%, in that 86% of all cases were in the same risk category in the referral and repeat cytologies. After excluding cases with "intermediate risk" referral or repeat cytology, we found that referral LR/repeat HR combination was seen in 49 (4.9%) of the 996 cases, whereas HR/LR and HR/HR combinations were seen in 3% and 3% of the 996 cases respectively. The sensitivity, specificity, positive predictive value, and negative predictive value on the ability of repeat cytology to detect the most clinically significant lesion (using findings from the concurrently obtained biopsy as gold standard) were 64%, 97%, 76% and 95% respectively. Overall, repeat cytology provided potentially clinically useful information in only 36 (3.6%) of the 996 cases, including 41% and 1.8% of the HSIL and LSIL referral cytology cases respectively.
Conclusions: Repeat cytology at the time of first colposcopy provides potentially clinically useful information in only a small percentage of cases overall, but in a substantial proportion of HSIL referral cytology cases, justifying its continued performance at least in this subset of patients.
Tuesday, March 1, 2011 9:30 AM
Poster Session III # 86, Tuesday Morning