1. Can Patterns Of Conversion From A Negative Initial Urine Cytology To A Positive Finding On Either
Subsequent Cytology Or Biopsy Be Used As A Benchmark For Surveillance In The Diagnosis Of
Urothelial Carcinoma?
Karen Chau, CT(ASCP)1; Lisa Rosen, ScM2; Constantinos Coutsouvelis, CT(ASCP)1; Ryan Brenkert, CT(ASCP)1;
Farah Slim, CT(ASCP)1; Ryan Glass, MD; Stephen Raab, MD3; Rubina Cocker, MD1
1Department of Cytopathology, NSLIJ, Lake Success, NY; 2Department of Biostatistics Unit, NSLIJ, Manhasset, NY;
3Department of Cytopathology, Eastern Health Laboratories, Newfoundland and Labrador.
Background
Methodology
Results
Conclusions
30-70% of patients treated for urothelial carcinoma
experience disease recurrence, with 10-30% of
these progressing to higher grade or invasive
disease. Urine cytology has been shown to be
highly specific in the detection of recurrent bladder
carcinoma and highly sensitive for detecting high-
grade lesions. As part of a greater study on the
accuracy of urine cytology, we explored patterns of
conversion from negative cytology to positive
findings on either cytology of biopsy.
A laboratory information system based search was
conducted for two tertiary hospitals and one
community hospital for the period from January
2008 to December 2010. The search identified 587
subjects (694 biopsy and cytology pairs) with
histological follow-up that occurred within six
months of urine cytology. Only subjects with
cytological and histological follow-up were included
in the study. We examined a subset of 176 positive
biopsies that occurred within two years of an initial
negative cytology to determine the amount of
cytology specimens needed prior to a positive
result, and the time needed for a positive result to
occur following the initial negative cytology.
66.5% of patients who eventually had a positive
biopsy had no prior positive cytology result. Of the
patients that did convert, 66.10% did so on the
second cytology, 20.34% on the third, and 6.78% on
the fourth, with fewer patients converting after each
subsequent specimen. A median of 2 cytology
specimens were required before a positive specimen
was encountered. The median time from the initial
negative to the first observed positive cytology was
1.4 months (IQR: 5.0 months). The median time from
the first negative cytology until positive biopsy was
5.5 months (IQR: 11.0 months).
Our study suggests that malignancies are most likely
to be found within two or three cytology samples,
after which likelihood is greatly diminished.
Furthermore, the median time for conversion of
negative cytology to positive cytology is much
shorter than that from negative cytology to positive
biopsy. This shorter time interval is helpful in
identification of earlier recurrences of urothelial
carcinoma and underscores the importance of
cytology as a more sensitive and efficient test. While
cytology may not be the sole determinant in the
triage of management, our study substantiates the
currently accepted three monthly follow up with
cytology as a post treatment urothelial carcinoma
surveillance regimen.
*Data in the above graph is for the subgroup of specimens that converted to a positive cytology (n = 59)
Number of Cytology Specimens observed until the
Initial Negative Cytology Converts to a Positive One*
Total Number of Cytology Specimens Observed
Prior to Receiving a Positive Biopsy