Collaboration was key to terminology, guidelines

The 2001 Bethesda System is the product of an April 30-May 2, 2001, workshop sponsored by the Bethesda, MD-based National Cancer Institute and numerous professional societies. In addition to the input received by the more than 400 workshop participants, even broader participation in the revision process was made possible through a dedicated web site ( More than 1,000 individual comments were received on the draft recommendations.

Representatives from 29 medical organizations and professional societies involved in women’s health care reviewed evidence from a broad range of studies to develop the Consensus Guidelines. The development of the guidelines was led by the Hagerstown, MD-based American Society of Colposcopy and Cervical Pathology, which sponsored a consensus workshop Sept. 6-9, 2001, in Bethesda. (Check the Society’s web page for information on the guidelines at

The new terminology and guidelines are the result of a further "fine-tuning" of the Bethesda System, says Michael Policar, MD, MPH, associate clinical professor of obstetrics, gynecology, and reproductive sciences at the School of Medicine in the University of California, San Francisco, and vice president for medical affairs at NorthBay Healthcare System in Fairfield, CA. He sees the most recent changes as "evolutionary, not revolutionary."

"The main difference over time is that the classification system and guidelines are becoming more evidence-based; many of the modifications in the 2001 Bethesda System are consequent to the findings in the ALTS [Atypical Squamous Cells of Undetermined Significance/Low-Grade Squamous Intraepithelial Lesion Triage Study] Trial,"1-4 he notes.

The 2001 Bethesda System’s terminology does eliminate some confusing terms and definitions and clarifies findings that require further evaluation, all which should help providers make decisions about appropriate follow-up care. But while the new format may make lab results easier to interpret, providers will need to carefully read the comments section to learn about cellular characteristics, say medical experts.


1. Solomon D, Schiffman M, Tarone RJ. Comparison of three management strategies for patients with atypical squamous cells of undetermined significance: Baseline results from a randomized trial. J Natl Cancer Inst 2001; 93:293-299.

2. Stoler MH, Schiffman M. Intraobserver reproducibility of cervical cytology and histology interpretations: Realistic estimates from the ASCUS-LSIL Triage Study (ALTS). JAMA 2001; 285:1,500-1,505.

3. Sherman ME, Solomon D, Schiffman M. Qualification of ASCUS. A comparison of equivocal LSIL and equivocal HSIL cervical cytology in the ASCUS LSIL Triage Study. Am J Clin Pathol 2001; 116:386-394.

4. Sherman ME, Schiffman M, Cox JT. Effects of age and human papilloma viral load on colposcopy triage: Data from the randomized Atypical Squamous Cells of Undetermined Significance/Low-Grade Squamous Intraepithelial Lesion Triage Study (ALTS). J Natl Cancer Inst 2002; 94:102-107.