College of American Pathologists
Printable Version

  PAP/NGC Program Review





cap today

January 2003
Q & A Feature


Q. What is the purpose of having the HSIL/carcinoma, NOS diagnostic category in the response menu of the Interlaboratory Comparison Program in Cervicovaginal Cytopathology?

A. The program added several diagnostic categories in 2000. The category HSIL/carcinoma, NOS is used primarily for educational slides illustrating high-grade processes and cancers not easily classified by other menu options. Examples include Paps that show features worrisome for an invasive process but that lack all of the classic features such as diathesis and prominent nucleoli. Other examples of HSIL/carcinoma, NOS cases are adenosquamous carcinomas and poorly differentiated carcinomas. Participants can also use this menu interpretation for cases in which they do not feel comfortable distinguishing between HSIL and invasive carcinoma. This may be a problem particularly for liquid-based Paps, in which diathesis may be more difficult to detect.

While it may be tempting to use the HSIL/carcinoma, NOS category as a “wastebasket” diagnosis to encompass all lesions that appear to be high-grade, participants are still encouraged to make a more specific diagnosis when possible. A participant response of adenocarcinoma or squamous carcinoma in a case with a reference diagnosis of HSIL would not be counted as a diagnostic error, because these diagnoses fall within the same diagnostic category for grading purposes. Thus there is no penalty for trying to distinguish between HSIL, squamous carcinoma, and adenocarcinoma. By attempting to make a specific diagnosis in most cases, participants can assess their diagnostic skills and maximize the educational value of the program.

Jonathan H. Hughes, MD, PhD
Laboratory Medicine Consultants, Ltd.
Las Vegas