Acetic acid recovery of gynecologic liquid-based samples of apparent low squamous cellularity

Acta Cytol. Mar-Apr 2006;50(2):136-40. doi: 10.1159/000325921.


Objective: To characterize cervicovaginal cytology samples with < 5,000 squamous cells on the initial ThinPrep slide (Cytyc Corp., Boxborough, Massachusetts, U.S.A) and to attempt sample recovery using acetic acid.

Study design: Cervicovaginal cytology samples with <5,000 squamous cells on the original ThinPrep slide and residuum were reprocessed by adding 3 mL of 3:1 CytoLyt (Cytyc)/glacial acetic acid with production of a second slide. Both slides were reviewed for squamous cell quantitation and the presence of background material and abnormal cells.

Results: From a total of 1,833 cases, 147 (8.0%) were identified for reprocessing; 71 (48.3%) were grossly bloody and 58 (39.4%) grossly cloudy. Reprocessing resulted in a second slide with > 5,000 squamous cells in 116 (78.9%) cases and was most effective on cloudy samples (89.7% recovery) and bloody samples (71.8% recovery). Abnormal cells were identified in 13 (8.9%) reprocessed samples. In all but 2 cases the abnormal cells were present on the initial slide and demonstrated the same degree of abnormality as the reprocessed slide but were fewer in number.

Conclusion: Acetic acid recovery increases squamous cell recovery when initially inadequate, reducing the number of unsatisfactory cases and in rare cases identifying a cytologically significant lesion not apparent on the original slide.

MeSH terms

  • Acetic Acid / chemistry*
  • Carcinoma, Squamous Cell / diagnosis*
  • Carcinoma, Squamous Cell / pathology
  • Cervical Intraepithelial Neoplasia / diagnosis*
  • Cervical Intraepithelial Neoplasia / pathology
  • Female
  • Humans
  • Sensitivity and Specificity
  • Vaginal Smears / methods*
  • Vaginal Smears / standards


  • Acetic Acid