Diagnostic Cytology
Fig. 15.38 Histology of renal cell carcinoma clear cell type (H&E x MP).
Fig. 15.39 Cells in catheterized urine from the same patient as Fig. 15.38
with clear cell carcinoma of the kidney. The tumor cells are arranged in
cluster and display vacuolated cytoplasm (Papanicolaou x MP).
Adenocarcinom as of the Prostate
These are common and are often well differentiated. Exfoliated
malignant cells may be seen and are diagnostic after prostatic
massage or instrumentation or in far-advanced disease when
the bladder is extensively infiltrated. Cytologic examination of
urine is rarely, if ever, a means of primary diagnosis and should
not be relied on. Fine-needle biopsies and aspirations are well-
established diagnostic procedures but lost ground to core biop-
sies and are rarely used. The cytologic appearance of neoplastic
urothelial cells frequently suggests the possibility of adenocar-
cinoma. This is because of prominent clustering, particularly of
papillary tumors, and the fact that the cytoplasm is often vacu-
olated and the nuclei may contain large nucleoli. Such findings
in a sputum specimen would definitely suggest that the neo-
plasm is an adenocarcinoma. In the great majority of positive
urine specimens, this is not the case and the tumor subsequently
is found to be a transitional cell carcinoma. Strong evidence of
adenocarcinoma must therefore exist, preferably in the form
of smooth-surfaced tissue fragments and clear characteristics of
adenocarcinoma. Mucicarmine and immunoperoxidase stains
may aid in the differential diagnosis.
Fig. 15.40 Cluster of neoplastic cells with large nuclei containing prominent
nucleoli. The cytoplasm is fairly well defined and slightly vacuolated. The cells
exfoliated from an advanced high-grade adenocarcinoma of the kidney
(Papanicolaou x HP).
Miscellaneous Tumors
Sm all-Cell Carcinom a of the Bladder
This is a rare undifferentiated tumor of the bladder with cytolog-
ical and histological appearance similar to small-cell carcinoma
of the lung43 (Figs 15.41 and 15.42). Urinary specimens show
small cells in loose clusters with salt and pepper chromatin pat-
tern. Immunocytochemical stains for neuroendocrine markers
show positivity in the cytoplasm of the tumor cells due to the
presence of neuroendocrine granules.
Sarcomas of the lower urinary tract include rhabdomyosarcoma
in children, adult-type rhabdomyosarcomas, carcinosarcomas,
and lymphomas. These tumors are rare, but a cytologic diagnosis
can be made if an adequate specimen is obtained and can be
correlated with the clinical history.
Special Aspects of Anatomic Sites
other than Urinary Bladder
Primary malignancies of the male and female urethra that are
unassociated with bladder tumors are rare. Squamous cell car-
cinomas are relatively most common, and most of the rest are
adenocarcinomas or urothelial carcinomas (Fig. 15.43). Primary
malignant melanomas and clear cell adenocarcinoma have also
been described and have cytologic features similar to these
tumors occurring at other sites.44
The most commonly required examination of a urethral spec-
imen is that after cystectomy for bladder carcinoma.45 Approxi-
mately 10% of patients who are treated for invasive transitional
cell carcinoma of the bladder develop neoplastic lesions in the
previous page 422 ComprehensiveCytopathology 1104p 2008 read online next page 424 ComprehensiveCytopathology 1104p 2008 read online Home Toggle text on/off