Rc. Anton et al., Should the cytologic diagnosis of "atypical squamous cells of undeterminedsignificance" be qualified? An assessment including comparison between conventional and liquid-based technologies, CANC CYTOP, 93(2), 2001, pp. 93-99
BACKGROUND. The diagnosis of atypical squamous cells of undetermined signif
icance (ASCUS) remains an enigma for the treating physician, because it enc
ompasses both benign, reactive, as well as preneoplastic and possibly neopl
astic conditions. To address this problem, The Bethesda System recommends q
ualifying the ASCUS diagnosis. This study analyzes the difference in the fo
llow-up results between the various groups of patients with an ASCUS diagno
sis as outlined by the Criteria Committee: favor premalignant (ASCUS-P), fa
vor reactive (ASCUS-R), and unqualified (ASCUS-C). The outcome, based on fo
llow-up biopsies and/or cytologies, for both the conventional Papanicolaou
smear (CS) and liquid-based (LB) methodologies is compared.
METHODS. The CS and LB biopsies and/or cytologies included 590 patients and
137 patients, respectively, who had an initial diagnosis of ASCUS. The fin
al outcome after subsequent biopsy and cytology within a 1-year period for
each methodology was tabulated. Furthermore, the addition of qualifiers for
each diagnosis was tabulated for both cytology and biopsy follow-up and co
mpared between CS and LB technologies.
RESULTS. For CS, 29 patients (8.6%) were found to have squamous intraepithe
lial lesions (SIL) on subsequent cytologic smears, and 176 patients (63.7%)
had SIL on biopsy follow-up. For LB, these numbers were 17 patients (19.1%
) and 56 patients (65.1%), respectively. Regardless of the qualification us
ed in the initial CS biopsy or cytology, over 90% of the subsequent smears
resulted in a benign diagnosis. Biopsy outcomes after CS diagnoses of ASCUS
-P, ASCUS-R, and ASCUS-C showed SIL in 80%, 53%, and 66% of patients, respe
ctively. For LB diagnoses, subsequent smears detected SIL in 33% of patient
s with a diagnosis of ASCUS-P, 22% of patients with a diagnosis of ASCUS-R,
and 12% of patients with a diagnosis of ASCUS-C. Biopsy outcomes after LB
diagnoses of ASCUS-P, ASCUS-R, and ASCUS-C showed SIL in 68%, 64%, and 66%
of patients, respectively.
CONCLUSIONS, There appears to be no statistically valid benefit from a clin
ical point of view in qualifying an ASCUS interpretation by either CS or LB
, except for CS evaluation of patients with a diagnosis of ASCUS-P. Cancer
(Cancer Cytopathol) 2001;93:93-99. (C) 2001 American Cancer Society.