Pap smears with glandular cell abnormalities: Are they detected by rapid prescreening?
Rapid prescreening (RPS) is one of the quality assurance (QA) methods used in gynecologic cytology. The efficacy of RPS has been previously studied but mostly with respect to squamous lesions; in fact, there has been no study so far specifically looking at the sensitivity of RPS for detecting glandular cell abnormalities. A total of 80,565 Papanicolaou (Pap) smears underwent RPS during a 25-month period. A sample was designated as "review for abnormality" (R) if any abnormal cells (at the threshold of atypical squamous cells of undetermined significance/atypical glandular cells [AGC]) were thought to be present or was designated as negative (N) if none were detected. Each sample then underwent full screening (FS) and was designated as either R or N and also given a cytologic interpretation. The final cytologic interpretation was a glandular cell abnormality (≥AGC) in 107 samples (0.13%); 39 of these (36.4%) were flagged as R on RPS. Twenty-four patients (33.8%) out of 71 who had histologic follow-up were found to harbor a high-grade squamous intraepithelial lesion or carcinoma; 13 of those 24 Pap smears (54.2%) had been flagged as R on RPS. Notably, 11 AGC cases were picked up by RPS only and not by FS and represented false-negative cases; 2 of these showed endometrial adenocarcinoma on histologic follow-up.
Pap smears with glandular cell abnormalities are often flagged as abnormal by RPS, and this results in a sensitivity of 36.4% (at the AGC threshold). Most importantly, some cases of AGC are detected on Pap smears by RPS only, and this demonstrates that RPS is a valuable QA method.