T H E AMERICAN JOURNAL OF CLINICAL PATHOLOGY
Vol. 36, No. 4, pp. 356-361
October, 1961
Copyright © 1961 by The Williams & Wilkins Co.
Printed in U.S.A.
HYDRONEPHROSIS RESULTING FROM OBSTRUCTION OF THE
URETHRA BY A POLYP OP THE VERUMONTANUM
H. J. BARRIE, B.M. (OXON.), AND D. C. SIMMS, M.D.
The Department of Pathology, University of Toronto, Banting Institute, Toronto, Canada
For nearly 100 years, urologists have been
removing polyps from the posterior urethra
through the urethroscope, and clinicians
have been responsible for all published
reports of them. In a worthwhile article in
1913, Randall 4 reviewed the scanty literature
on polyps, and described 9 examples from
his own practice. Reports of cases came
from Thomas 7 in 1922, Valverde8 in 1933,
Lazarus3 in 1933, Riches 5 in 1944. and
Houke,2 in 1945.
Some polyps have been ascribed to
gonococcal periurethritis, and others categorized as villous, angiomatous, fibrous, fibromyomatous, and adenomatous.
This paper deals with the clinicopathologic findings in a 35-year-old man who had
a polyp that was observed at necropsy to be
obstructing the posterior urethra. It was
hanging from the colliculus, but contained
mucous glands similar to Cowper's glands.
In trying to determine its origin, we became
interested in what the various categories
of reported polyps really meant in terms of
neoplasia, and this has led to the conclusion
that true benign neoplasms of the urethra
are even rarer than the scarce reports on
them would indicate.
R E P O R T OF CASE
Clinical history. This 35-year-old man
had been a heavy drinker for 20 years. Six
weeks before death he became increasingly
hoarse and complained of some weakness of
the arms. His hoarseness increased, and 7
days before death he had complete laryngeal
paralysis. His hemoglobin was 48 per cent,
and the leukocyte count was 21,000 with 90
per cent polymorphonuclears. His blood
pressure was 125/65. The patient became
Received, January 21, 1961; revision received,
March 27; accepted for publication May 31.
Dr. Barrie is Professor of Pathology at the
University of Toronto; Dr. Simnis is Assistant
Resident in Medicine at the Wellesley Hospital.
drowsy and disoriented. His intake of
fluid was more than 200 ml., and his output was 550 ml. His urine had a specific
gravity of 1.006, albumin 3 + , with granular
casts, and red and white cells in the deposit.
His non-protein nitrogen (NPN) was 170
mg. per 100 ml., and his C0 2 -combining
power was 17.4 volumes per 100 ml., decreasing to 12.6. The cerebrospinal fluid
contained 60 mg. of protein per 100 ml.,
50 red blood cells and 2 lymphocytes per
cu. mm., and manifested a pressure of 330
mm. of water. He developed a pericardial
friction rub, and rapidly declined.
Necropsy findings. The heart was moderately hypertrophied (weight, 530 Gm.), and
there was a fibrinous uremic pericarditis.
Numerous small foci of necrosis were
scattered throughout the pons, medulla,
and the white matter of the cerebellum.
The cause of these was obscure. The features
that are of chief interest to this paper were
in the urinary system.
Urinary system. A pedunculated cylindrical polyp, 3.4 cm. in length and 1 cm.
in diameter was hanging from the colliculus
(Fig. 1). Its free end lay in a slight dilation
of the membranous urethra. It was covered
by smooth mucosa, but there had been
some bleeding from the end, and the tip
was dark and covered with fibrin.
The prostate gland was small and symmetrical. Its posterior bar was 0.5 cm. in
width, and the 2 lateral lobes were 1.4 cm.
in width. The cut surface of the prostate
gland was firm and stippled with yellow.
The bladder was hypertrophied, shrunken,
empty, and measured 1 cm. in thickness.
The seminal vesicles were 3 cm. in length
and up to 2 cm. in diameter, and seemed
to be normal.
The testes seemed to be normal, in the
gross and microscopic examinations.
Both ureters were uniformly dilated up
to 2.2 cm. in circumference, and had linear
356
Oct. 1961
URETHRAL
357
POLYP
. f 17'
1
iii:/
J •
FIG. 1. Gross appearance of polyp hanging from verumontanum
markings on the mucosa and rather thick
walls. Their entry into the bladder was
unobstructed.
The weight of the left kidney was 75
Gm., and of the right kidney, 70 Gm. In
each, the pelvis was chiefly extrarenal, and
formed a pyramid 6 cm. in length. The
pelvis communicated by relatively undilated secondary calyces, with moderately
and uniformly dilated calyces. In the upper
pole of the left kidney, the whole system
was dilated. Two deep clefts were present
in the left kidney where the renal tissue had
been completely absorbed, and in the
remaining renal tissue there was no differentiation between cortex and medulla. The
papillae were blunt and congested. In each
kidney the capsule was adherent to a
granular surface, and the cortex was narrow
and peppered with yellow granules.
Microscopic examination revealed the
renal atrophy to be owing chiefly to membranous glomerulonephritis, but there were
also a few scars of healed pyogenic nephritis.
The polyp. Multiple transverse microscopic sections were made at intervals
through the polyp. Its main bulk was
observed to consist of hypertrophied,
longitudinally running bands of smooth
muscle surrounding a core containing
dilated blood vessels. The fibers of smooth
muscle at the base of the peduncle were cut
in cross or oblique sections, and were not
continuous with the main bulk of muscle
in the body of the colliculus and prostate
gland. They were, therefore, probably
derived from the submucosal longitudinal
muscle of Henle. In the distal third of the
polyp (Fig. 2) there were 2 tubuloacinar
mucous glands on each side, the most
358
BARRIE AND SIMMS
distal of each pair manifesting considerable
necrosis. The clear areas, marked "gl" in
Figure 2, are composed of mucus in the
cytoplasm of these glands, which stained
strongly with mucicarmine and alcian blue.
The structure of the glands was similar
to Cowper's glands, which are, of course,
normally situated much farther down the
urethra in the urogenital diaphragm.
The congestion of the tip of the polyp
was reflected in the microscopic sections by
partial infarction and ulceration of the
surface.
The ejaculatory ducts ran lateral to the
stalk of the polyp and, as the interval
sections progressed caudally, the sinus
pocularis became visible between the ducts
and was seen to open just below it (Fig. 3).
The sinus had a notably simple structure,
being devoid of any of the usual glandular
infoldings. The prostatic glands also manifested fewer infoldings than are normal in a
man of this age.
DISCUSSION
This man's death from uremia was more
the result of membranous glomerulonephritis
than obstruction of the urethra, but the
latter had produced a considerable degree of
hydroureter and hydronephrosis.
The appearance of mucinous glands in
the polyp set it apart from any cases that
have previously been published. These
glands, the configuration of the polyp, and
the fact that it was hanging from the
colliculus, made us wonder at first if it
represented an anomalous development of
cervical tissue from the remnants of the
Miillerian duct. The discovery of the sinus
pocularis opening independently below it
made this supposition most improbable. To
go any further in understanding the genesis
of this tumor, one must examine it against
the background of what has already been
recorded regarding benign tumors of the
posterior urethra.
They have been classified as fibroma,
fibromyoma, adenoma, and papilloma. The
words suggest that we are dealing with
true benign neoplasms, but if one looks a
little more deeply into these reports, it
seems that a true benign neoplasm of the
Vol. 86
posterior urethra must be very uncommon.
Good histologic descriptions of tumors
removed from this area are extremely rare.
If one examines the available ones, the
applicability of the term "benign neoplasm" becomes doubtful. The "adenomas"
pictured, for example, by Randall and
Houke, reproduced the structure of the
small glands which are normally found
under the mucosa of the posterior urethra
and colliculus, and give the impression of
slightly hyperplastic or inflamed glands
that have become polypoid because of the
recurrent contractions of the urethra. These
superficial glands, like the prostate gland,
do not produce mucin.
There are 3 reasons why superficial
submucous swellings on the colliculus, of
whatever origin, may become polypoid.
The first is the powerful expulsive action
of the muscular walls of the urethra. The
second is the fact that the colliculus is
already projecting into the lumen, and that
any swelling not intimately tethered to the
deeper structures would be particularly
liable to the propelling action of muscular
contraction. The third is the disposition of
Henle's muscle running longitudinally directly beneath the mucosa. The small
glands superficial or just deep to it would
find it of poor assistance in resisting dislocation into the lumen and, as apparently
had happened in our patient, would in fact
have dragged it along with them. A coil
of abnormal blood vessels would behave
in the same way, which would account for
polypi such as those described by Takahashi
and Tsuchiya6 as being composed of "angiomatous" vessels and smooth muscle. There
is no need to invoke any consideration of
hamartomatous malformations.
The relation of "fibrous" polyps to
chronic inflammation, usually gonococcal,
of the tract was reported by Valverde, 8
who described 39 instances of fibroepithelial
hyperplasias forming polypi, 33 of which
arose from the colliculus. These were all
related to posterior urethritis, and it is
doubtful if they represented true neoplasms.
The formation of this type of polyp is
illustrated in Figures 4 and 5, which are
taken from material removed at operation
Oct. 1961
URETHRAL
POLYP
359
F I G . 2 (upper). Body of polyp. The central stripe is composed of
smooth muscle. One gland on each side opens near the tip, the other
near the mid-point. Hematoxylin and eosin. X 10.
F I G . 3 (lower). Section through verumontanum. The pedicle of the
polyp is to the right. Behind it the sinus pocularis may be observed as a
slit with dark walls, with ejaculatory ducts above and below it. Hematoxylin and eosin. X 5.7.
by Dr. W. K. Kerr from the prostatic
urethra of a man 64 years of age. Multiple
polyps were present in this man's urethra,
and sections from them demonstrated them
to be of all ages. It was possible to follow
their evolution. They started with a bleb of
submucous edema which, together with the
overlying epithelium, next formed a tubular
or cone-shaped projection. Some of them
had then undergone spontaneous regression
by atrophy of the epithelium and loss of
fluid from the body of the polyp. Such a
withered filiform polyp can be seen in
partial section in Figure 4.
Because villous papillomas are so common
in the bladder, one could expect that a
surface manifesting the same sort of epithelium and situated so close to the bladder
360
Vol. 36
BARBIE AND SIMMS
«*'-.•
• •>! • ' - . ' ' a f f i a S
F I G . 4 (upper). " I n f e c t i v e " polyps from the prostatic urethra. T h e
large one is composed of edematous connective tissue. The very thin
one, apparently lying free, is an atrophied polyp t h a t has lost its fluid
and become filiform. Hematoxylin and eosin. X 3.25.
F I G . 5 (lower). Greater magnification of tissue from t h e base of the
polyp in Figure 4. Small polyps are forming in relation to blebs of
edema fluid. Hematoxylin and eosin. X 60.
would also be subject to this type of tumor.
They have been described in the gross
examination as delicate, feathery projections
by Thomas, 7 and an illustration of a villous
papilloma is included in Randall's paper.4
Photographs of this one are illustrated
under low and high power, and it seems
probable to us that the so-called villi were
really the dilated metaplastic infoldings of
superficial glands. The gross description in
the text tallies with this latter interpretation.
An illustration of a transitional cell papilloma of the prostatic urethra is presented
without details by Dixon and Moore.1
This discrepancy in the incidence of
tumors in the urethra and the bladder holds
true for the malignant tumors, as well as
for the benign ones, and it seems that we
should be able to use this fact in analyzing
the causes of the common as well as the
increasingly frequent tumors of the bladder.
The easiest explanation, of course, is that
the important factor is the length of time
in which the epithelium is in contact with
carcinogens in the urine.
The polyp described by us was, of course,
not a papilloma. It had apparently been
formed by the extrusive action of the
muscle of the urethra on the mucous glands
at its tip. The only problem was: what
Oct. 1961
URETHRAL
were the mucous glands doing there in the
first place? They had the ordinary branching
and histologic structure of Cowper's glands,
and it is highly unlikely that metaplasia
of any of the simple tubular glands of the
urethra could have simulated this pattern.
We think, therefore, that they represented
an ectopia of Cowper's glands. Unfortunately, the membranous urethra was discarded before we realized what the problem
was going to be, and we can not say whether
or not there were also mucous glands in
the urogenital diaphragm. As is so often the
case after a necropsy, the prosectors would
also have welcomed a chance to chat with
the patient about his symptoms.
SUMMARY
1. This paper deals with the clinicopathologic findings in a 35-year-old man
who had chronic urinary obstruction caused
by a polyp hanging from the colliculus.
2. The polyp contained mucous glands
(probably ectopic Cowper's glands), and
this makes it distinct from any previously
reported urethral polypi.
3. Practically all of the polypi described
in the literature can be attributed to
attempts at extrusion of localized swellings
in the mucosa by the muscular urethra.
4. True benign tumors of the urethra
must be extremely rare, and this fact should
be of some value to us in assessing the
causes of the very frequent neoplasms of
the bladder.
SUMMARIO I N
INTERLINOUA
1. Iste communication presenta le constatationes clinico-pathologic in un masculo de
361
POLYP
35 annos de etate qui habeva chronic
obstruction urinari causate per un polypo
pendente ab le colliculo seminal.
2. Le polypo contineva glandulas mucose
que probabilemente esseva ectopic glandulas
de Cowper. Isto rende le caso distincte de
omne previemente reportate polypos urethral.
3. Practicamente omne le polypos describite in le litteratura pote esser attribuite a
un pression extrusional exercite per le
urethra muscular contra tumescentias localisate in le mucosa.
4. Ver tumores benigne del urethra debe
esser extrememente rar. Iste facto pote esser
de valor pro nos in evalutar le causas del
frequentissime neoplasmas del vesica.
REFERENCES
1. D I X O N , F . J., AND M O O R E , R. A.:
2.
3.
4.
5.
Tumorsofthe
male sex organs. In A F I P Atlas of Tumor
Pathology, F a s . 32: 105, 1952.
H O O K E , E . M . : Papillomas of t h e verumontanum. J . Iowa M . S o c , 35: 427^28, 1945.
LAZARUS, J . A.: P r i m a r y benign tumors of the
u r e t h r a : report of 3 cases. Urol, and Cutaneous Rev., 37: 604-607, 1933.
R A N D A L L , . A . : A s t u d y of t h e benign polyps of
the male u r e t h r a . Surg. Gynec. & Obst., 17:
548-562, 1913.
R I C H E S , E . W . : Papillomata of the u r e t h r a .
Brit. J . Urol., 16:12-15,1944.
6. T A K A H A S H I , A., AND TSUCHIYA, F . : Ein aus dem
Colliculus seminalis stammender Polyp.
Jap. J . D e r m a t . & Urol., 4 1 : 169-170, 1937.
7. THOMAS, G. J . : Papilloma of t h e bladder and
posterior u r e t h r a . Urol, and Cutaneous
Rev., 26: 135-136, 1922.
8. VALVERDE, B.: Polypi a n d vegetations of the
posterior u r e t h r a ; their influence o n t h e
sexual disturbances of men. Urol. &
Cutan. Rev., 37: 461-166, 1933.
CORRECTION
I n t h e article entitled " E v a l u a t i o n of a R a p i d D y e - R e d u c t i o n T e s t for Bacterial
Susceptibility to Antibiotics," b y Bieringer a n d Miale (the J O U R N A L , 3 6 : 195-202,
September 1961), t h e concentrations for streptomycin (p. 196) should have been
expressed in units, rather t h a n micrograms.