Reprinted from October 1996 CAP TODAY
Q: Do the Clinical Laboratory Improvement Amendments of 1988 mandate
that all Pap smears classified as "cellular changes associated with
inflammation" be reviewed by a pathologist?
A: CLIA ’88 mandates that pathologists review Pap smears with reactive
or reparative changes.1 Because “cellular changes associated
with inflammation” are reactive, I interpret the CLIA rule as requiring
Important practical problems are, however, associated with Bethesda System
diagnoses of noninfection benign cellular changes. First is the threshold
for interpreting features as BCC rather than as within normal limits.
Wide variation can be found among cytologists and laboratories regarding
this threshold, with some having very high rates of BCC and others very
low, or even zero, rates; high rates would require the pathologist to
review many negative cases, which may not be feasible.
Second, BCC can be an interpretive trap. A recent CAP Q-Probe about retrospective
review of negative smears preceding diagnosis of high-grade intraepithelial
lesion or carcinoma found that the earlier BCC smears were more likely
to be false-negative than the earlier within normal limits/negative smears;
three-fourths of the errors for within normal limits/negative cases were
screening errors, but more than two-thirds of the BCC errors were interpretive.2
This finding gives support to the practice of rescreening or hierarchic
review of cases screened as BCC, or both.
Third, some clinicians and pathologists perceive that BCC is an abnormal
diagnosis that requires action. The effect can be unfortunate, causing
women with no evidence of an epithelial cell abnormality to undergo unnecessary
and distressing procedures. Two thoughtful editorials about this problem
appeared in Diagnostic Cytopathology in 1994.3, 4
The undersigned author’s laboratory addresses the issue by not reporting
noninfection BCC diagnoses. Cases in that category undergo pathologist
review, and the pathologists revise some of the diagnoses to atypical
cells of undetermined significance or worse. However, if the pathologist
agrees that the changes do not represent an epithelial cell abnormality
and thus require no clinical action, the diagnosis is within normal limits,
and the interpretation of BCC is placed in the laboratory record but is
The current edition of the CAP Laboratory Accreditation Program cytopathology
checklist requires pathologist review of cases showing repair, but not
those with reactive changes; this practice was recommended by the CAP
Cytopathology Committee. The LAP has deeming authority under CLIA’88 to
accredit laboratories in cytopathology, and this checklist item has been
approved by the Health Care Financing Administration.
For the aforementioned reasons, however, CAP-accredited laboratories
may want to follow the CLIA final rule requirement for pathologist review
of reactive changes or, altematively, may submit all or many BCC cases
for cytotechnologist rescreening. The primary goal would be to identify
those cases for which the diagnosis should be upgraded to an epithehal
cell abnormality, with a secondary goal of downgrading BCC interpretations
to “within normal limits” when appropriate.
1. United States Department of Health and Human Services, Clinical Laboratory
Improvement Amendments of 1988 Final Rules. Federal Register. Feb.
2. Jones BA. Rescreening in gynecologic cytology: Rescreening of 3,762
previous cases for current high-grade squamous intraepithelial lesions
and carcinoma--a College of American Pathologists Q-Probes study of 312
institutions. Arch Pathol Lab Med. 1995;119:1097-1103.
3. Luff RD. Benign cellular changes: Have we inadvertently reinvented
the Class H cytology sign-out? Diagn Cytopathol. 1994;10:309-310.
4. Young NA, Kline TS. Benign cellular changes: Allied ambiguity in CLIA
‘88 and The Bethesda System. Diagn Cytopathol. 1994;10:307-308.
Mary Nielsen, MD
Chair, CAP Cytopathology Committee