Papanicolaou test interpretations of “atypical squamous cells, cannot exclude high‐grade squamous intraepithelial lesion”

BACKGROUND. Management guidelines for women with Papanicolaou (Pap) test interpretations of ASC‐H (atypical squamous cells, cannot exclude high‐grade squamous intraepithelial lesion) reflect substantial risk, which ranges from 10% to 68%, of a cervical intraepithelial neoplasia grade 2 or worse (CIN2+) in their follow‐up histologic samples. The present study was initiated to determine the number of colposcopic procedures and the time frame that are typically required for a definitive diagnosis of a CIN2+ lesion after a Papanicolaou (Pap) test interpretation of ASC‐H in routine practice. METHODS. Clinicopathologic data on consecutive ASC‐H interpretations, 97% of which were on liquid‐based preparations, were reviewed. The number of biopsies (which was used in this context as a surrogate indicator for the number of colposcopic procedures) as well as the average duration required for a follow‐up histologic diagnosis of CIN2+ were determined. RESULTS. Of 500 ASC‐H interpretations, 75 were excluded for a variety of reasons and 165 lacked follow‐up in our records. The average age and follow‐up duration for the remaining 260 patients was 35.6 years and 18.5 months, respectively. CIN2+ was diagnosed in 49 (40%) of the 122 patients with at least 1 histologic follow‐up. Of these 49 patients, 72% (35 of 49) were diagnosed on the first follow‐up cervical biopsy, 14% (7 of 49) and 8% (4 of 49) were diagnosed on the second and third follow‐up biopsies, respectively; in only 6% (3 of 49) was a fourth follow‐up biopsy required. Overall, an average of 1.53 biopsies (range, 1–4) was required to attain a definitive diagnosis of CIN2+, and 28% of patients required more than 1 follow‐up biopsy. The average period between the index ASC‐H interpretations and CIN2+ diagnoses was 5.5 months. The average time to CIN2+ diagnoses by the first follow‐up biopsy was 3 months; for diagnoses made on subsequent biopsies, the average additional follow‐up duration was 8 months. Of the eventual CIN2+ diagnoses, 84% were rendered within 12 months of their associated index ASC‐H interpretations. CONCLUSIONS. 1) A substantial subset—28%—of patients with biopsy‐proven CIN2+ after ASC‐H interpretations required more than 1 colposcopy for a definitive diagnosis of a high‐grade dysplastic lesion. 2) If a CIN2+ lesion is present, the vast majority can be diagnosed in a biopsy performed within 1 year of the ASC‐H interpretation. Cancer (Cancer Cytopathol) 2007. © Published 2007 by the American Cancer Society.