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Squamous Epitheliuai in the Trigone of the Human Female Urinary Bladder
THE JOURNAL OF' UROLOGY
Vol. 73_ No. 5, May 1955 Printed in U.S.A.
SQUAMOUS EPITHELIUM IN THE TRIGONE OF THE HUMAN FEMALE URINARY BLADDER WITH A NOTE ON CYSTOSCOPIC OBSERVATIONS DURING ESTROGEN THERAPY
CHARLES NEY
AND
JOSEPH C. EHRLICH
From the Surgical Service and Department of Laboratories, Lebanon Hospital, New York, N. Y.
For many years, observers1, 2 , 3 , 4 , 5 • 6 , 7 , 8 • 9 • 10 have recognized the occurrence on the trigone of the human female bladder of grayish-white patches which have been described as chronic trigonitis, pseudomembranous trigonitis, trigonitis areata alba, etc. Cifuentes 11 • 12 clarified the nature of these patches; he noted that histologically they were composed of squamous epithelium and stated that they occurred exclusively in the trigonal mucosa of females. He stressed the resemblance to vaginal mucosa. The patches under consideration occur on the trigone of females most frequently during their active sex life; their frequency appears to diminish with age, but we have observed them in the sixth, seventh and eighth decades. Such areas have never been reported in prepubertal females or in infants; hmvever, one of us (J. C. E.) observed one such area in serial sections of the trigone of a newborn female infant. Grayish-white patches similar to those which occur in the female have rarely been described in males. Cifuentes12 had never seen one in a male, and Heymann13 reported their absence in five men studied. It should be emphasized that we are not concerned here with squamous metaplasia due to calculi, tumors, ulcers and trauma. In a routine study of five hundred consecutive autopsies of both sexes and all age groups, the present authors have not observed squamous patches of this type in a single male. This study was aided by a grant from the Aaron W. Davis Foundation. Read at annual meeting, American Urological Association, New York, K. Y. June 3, 1954. 1 Pelouze, P. S.: Trigonitis area ta alba. Surg., Gynec. & Obst., 39: 510, 1924. 2 Ryall, E. C.: Pseudomembranous trigonitis. Brit. J. Urol., 1: 255-257, 1929. 3 Orr, L.: Chronic pseudomembranous trigonitis. South. Med. J., 26: 359-361, 1933. 4 Pelouze, P. S.: Obscure pseudomembranous trigonitis. Trigonitis areata alba. Ann. Surg., 101: 594-598, 1935. 5 Fowler, H. A.: Pseudomembranous trigonitis with observations of bladder dysfunction in the female" Urol. & Cutan. Rev., 40: 156-163, 1936. 6 Douglass, H. L.: Chronic trigonitis: Its effect on trigonal epithelium. J. Tenn. l\Ied. A., 33: 261-267, 1940. 7 Douglass, H. L., Ransom, B. S. and Webster, B. H.: Some further studies on trigonitis. J. Tenn. Med. A., 25: 254-259, 1942. 8 Cifuentes, L.: Estudios sobre las trigonitis. Rev. clin. espan., 11: 171-177, 1943. 9 Matheson, N. M.: Some diseases of the female urinary bladder. Tr. M. Soc. London, 64: 117-127, 1943-46. 10 Brown, H. E.: Chronic urethrotrigonitis in the female. Pennsylvania Med. J., 53: 489-493, 1950. 11 Cifuentes, L.: Epitelio de tipo vaginal en la vejiga urinaria de Ia mujer. Rev. clin. espan., 20: 54-56, 1946. 12 Cifuentes, L.: Epithelium of vaginal type in the female trigone. The clinical problem of trigonitis. J. Urol., 57: 1028-1037, 1947. 13 Heymann, A.: Die Cystitis Trigoni Chronica der Frau und ihre pathologische Anatomie. Beitrage zur Metaplase des Blasenepithels. Centralblatt for die Krankheiten der Harn und Sexual-Organe, 17: 177-192, 1906.
809
810
CHARLES NEY AND JOSEPH C. EHRLICH
The presumed origin14 of these patches in the female from epithelium of the urogenital sinus suggested the possibility that these foci in the urinary bladder might respond to estrogenic stimulation in a fashion similar to the well-known response of related mucosa in the reproductive tract. Reports15 • 16 • 17 • 18 , 19 • 20 of results of experiments in animals strengthen this hypothesis. As far as can be ascertained, there are no reports indicating direct evidence of histological changes in the mucosa of the human urinary bladder following estrogenic stimulation. The following is a report of three cases in which changes in squamous patches in the mucosa of the trigone in women appeared to be related to the administration of estrogenic substances. CASE REPORTS
Case 1. M. N., a 33 year old white woman, presented herself on September 12, 1949 with the chief complaints of difficulty of urination, frequency of urination, and pain following urination for 2 years. In September 1936, a partial resection of a cystic left ovary had been performed. In January 1939, the left tube, the remainder of the left ovary, and the right tube had been removed; the transcript of the findings at this operation stated that the right ovary was absent. One month before this latter operation, menopausal symptoms consisting of flushes, weakness, and nervousness began; these have continued until the present, although they are now somewhat less severe. The general physical examination of September 12, 1949 was essentially negative. Urine examination revealed no abnormalities. Observation cystoscopy revealed a granular urethritis and a mild stenosis of the external urethral meatus. The bladder appeared normal. After a few dilatations of the urethra, the patient did not return; she was not seen again until October 1951. At that. time, many cysts of the neck of the bladder were found on cystoscopy. The mucosa of the bladder, including the t.rigone, was normal. She was admitted to Lebanon Hospital on December 11, 1951. Culture of the urine was sterile. The cysts in the neck of the bladder from 9 to 3 o'clock were fulgurat.ed under pent.othal sodium anesthesia on December 12, 1951. At the same time, specimens of the trigone of the bladder were taken by biopsy, although no abnormalities could be seen. The report of the histological findings follows : Sections revealed small fragments of mucosa from the urinary bladder. The 14 Zuckerman, S.: The histogenesis of tissues sensitive to oestrogens. Biol. Rev., 15: 231-271, 1940. _ 15 Lacassagne, A.: Modifications de L'Epithelium Vesical Chez La Souris Atteinte de Retention Urinaire a La Suite d'Injections d'Oestrone. Comptes Rendus Hebdomadires des Seances et Memoires de La Societe de Biologic, 120: 833-855, 1935. 16 Raynaud, A.: Modifications Apportees Precocement Dans La Structure de La Vessie etde L'Uretre du Chat Par Des Injections de Dihydrofolliculine. Comptes Rendus Hebdomadiares des Seances et Memoires de La Societe de Biologic, 126: 215--217, 1937. 17 Burns, R. K., Jr.: Effects of female sex hormones in young opossums. Proc. Soc. Exper. Biol. & Med., 41: 270-272, 1939. 18 Burns, R. K., Jr.: Sex differentiation during the early pouch stage of the opossum (Didelphys Virginiana) and a comparison of the anatomical changes induced by male and female sex hormones. J. Morphol., 65: 497-548, 1939. 19 Burns, R. K., Jr.: Origin and differentiation of epithelium of urogenital sinus in the opossum. Proc. Soc. Exper. Biol. & Med., 47: 106-108, 1941. . 20 Moore, C.R.: On the role of sex hormones in sex differentiation in the opossum (Didelphys Virginiana). Physiol. Zool., 14: 1-47, 1941.
SQUAMOUS EPITHELIUM IN TRIGONE
811
epithelium was uniformly of the transitional type with flattened surface cells. There were no significant abnormalities of the lamina propria. Stains for glycogen revealed minimal amounts in the basal layer of the epithelium. Diagnosis: N onnal mucosa of urinary bladder. The patient was discharged from the hospital on December 13, 1951. Therapy with premarin (2.5 mg. daily, orally) was begun on December 21, 1951. On January 4, 1952, a cystoscopy was performed in the office, and at this time four grayish-white, raised, granular patches could be seen on the trigone of the bladder, varying in diameter from 3-5 mm. Two of these were situated near the vesical neck to the right and left of the midline. Two others were situated just distal to the right and left ureteral orifices. There were a few cysts still present on the neck of the bladder between 5 and 7 o'clock. Premarin was taken without interruption until admission to Lebanon Hospital on .January 14, 1952. On January 15, 1952, under pentothal sodium anesthesia, specimens of the grayish-white patches on the trigone were taken by biopsy. The cysts of the vesical neck were now thoroughly fulgurated. The report of the histological findings follows: Sections revealed fragments of mucosa from the urinary bladder containing areas of squamous epithelium. The latter was focal in distribution; the intervening epithelium was of the transitional type. The squamous epithelium vrns six to fifteen layers in width, and the superficial cells contained large perinuclear clear areas in which considerable amounts of glycogen were demonstrated by special stains. Foci of parakeratosis were noted. There appeared to be slight intraepithelial comification. The lamina propria showed vascular engorgement and a slight infiltration by lymphocytes. Diagnosis: Fragments of vesical mucosa containing foci of squamous epithelium of the trigonal type (fig. 1). Case 2. F. C., a white woman, 44 years of age, was first seen on December 8, 1950. Her chief complaint was increasing frequency of urination for 6 months; recently she had been voiding every half hour. One month previously (N ovember, 8, 1950) her family physician had started her on premarin, 1.25 mg. daily orally because she had been complaining of hot flushes, nervousness and dizziness. The patient had had a vaginal hysterectomy with a perineorrhaphy 10 years ago when she was thirty-four. The ovaries had not been removed. General physical examination disclosed essentially normal findings. Urine examination (catheterized specimen) showed only a rare leukocyte. On December 14, 1950, a cystoscopy was performed in Lebanon Hospital. A few cysts were present in the neck of the bladder, but the urethra, trigone and rest of the bladder showed no abnormalities. Cultures of urine from bladder and both kidneys were sterile. Due to a questionable finding in the left pyelogram, it was decided to repeat the cystoscopy after an interval of several months. The patient had been taking premarin continuously for nearly 4 months; it had been stopped on March 1, 1951. A cystoscopy was performed on March 8, 1951. A left retrograde pyelogram was considered normal. A grayish-white, raised patch was observed on the trigone proximal to the neck of the bladder and distal to the right ureteral
812
CHARLES NEY AND JOSEPH C. EHRLICH
I'
FIG. 1. Case 1. A, biopsy of trigone. Characteristic foci of squamous epithelium of trigonal type arranged in tiny plaques, some of which are connected by narrow bridges of transitional epithelium. Note festooned contour to basal zone of epithelium with intervening projections of lamina propria resembling papillary zone of dermis. Patient had been on estrogenic therapy. B, selected area from A at higher magnification to show gradual change in polarity from basal to superficial polyhedral cells. N" ote large, perinuclear clear areas and intercellular "canals."
SQUAMOUS EPITHELIUM IN TRIGONE
813
orifice. It was about 5~7 mm. in dianieter, smooth and glistening in appearance. A specimen was taken by biopsy from this area. The report of the histological findings follows: Section revealed a fragment of mucosa from the urinary bladder. The lamina propria was covered by broad epithelium of the squamous type. The basal zone of the epithelium consisted of compactly arranged cells with dark nuclei, and was two to four layers in width. The polyhedral layer was three to eight rows in width, and many of these cells had large perinuclear, clear areas whose appearance suggested the presence of glycogen; this was confirmed by special stains. Normal epithelium of the transitional type did not appear in the specimen. Diagnosis: Fragments of vesical mucosa; epithelium entirely of squamous trigonal type (fig. 2, A). The patient took no more estrogenic substances after March 1, 1951. She was readmitted to Lebanon Hospital on July 9, 1951. On July 12, 1951, cystoscopy was done under general anesthesia. Although no patch was seen in the trigone, five specimens were obtained by biopsy in the vicinity of the previous lesion. The report of the histological findings follows: Sections revealed fragments of mucosa from the urinary bladder with foci of squamous epithelium appearing as patches or islands in otherwise normal transitional epithelium. These squamous foci were thinner than those in the specimen of March 7, 1951. The basal zone had two to four layers of cells, and the polyhedral layer also had two to four rows. Perinuclear vacuolization was much less conspicuous. Stain for glycogen disclosed minute amounts in the transitional epithelium; squamous foci did not appear in the fragments which had been placed in special fixative for glycogen stains. There was inflamn1ation of the lamina propria. Diagnosis: Fragments of mucosa from the urinary bladder showing a few relatively thin foci of squamous epithelium (fig. 2, B). Therapy with premarin, 1.25 mg. daily, orally was reinstituted on July 24, 1951, and was continued until re-admission to Lebanon Hospital on October 31, 1951. On November 1, 1951, a cystoscopy ·was performed. A raised, grayishwhite, smooth, glistening mound, 3 mm. in diameter was observed in the same region as the original lesion. Specimens were taken from this area. The report of the histological findings follows: The section consisted of three fragments of tissue from. the urinary bladder. One of these was covered by relatively normal transitional epithelium. A second was covered partly by transitional and partly by squamous epithelium. A third fragment was covered entirely by squamous epithelium. The appearance of the squamous area was similar to that in the first specimen taken about eight months previously. Diagnosis: Fragments of mucosa from the urinary bladder containing foci of squamous epithelium of the trigonal type (fig. 3). Case 3. M. B., a 49 year old white woman, came to the office on April 23, 1952, complaining of hematuria of 5 days' duration. The past history was noncontributory, except that for 2 years she had been going through the menopause and complaining of hot flushes, nervousness and irregular menstruation. Physical examination was essentially negative. Cystoscopy was performed at the office
814
CHARLES NEY AND JOSEPH C. EHRLICH
,!it.
FIG. 2. Case 2. A, biopsy of trigone. Area illustrated is entirely covered by squamous epithelium of trigonal type. Patient had been on estrogenic therapy 4 months. B, biopsy of trigone 4 months after cessation of estrogenic therapy. Area illustrated covered partly by transitional and partly by thinned out squamous epithelium. Inflammation of lamina propria.
SQUAMOUS EPITHELIU!VI IN 'J'RIGONE
815
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·• - .•
ti,;
'' Fm. 3. Case 2. Same case as figure 2. Biopsy of trigone 3 months and 7 days after resumption of estrogenic therapy. Area illustrated covered entirely by squamous epithelium of trigonal type. Superficial layers of cells are compact, flattened, nonvacuobted ,Yith persistent nuclei and present appearance of parakeratosis.
and again in the hospital the following day. Just lateral to the right ureteral orifice was a 2~3 mm., papillomatous growth, with a thin stalk, The trigone was normal, Upper tracts were normal, and there -rrns no growth on culture from either kidney or bladder. The patient was anesthetized with intravenous sodium pentothaL A specinien of the growth was taken by biopsy. The histopathological report was, "Fragments of papilloma of the urinary bladder; fragments of inflamed vesical mucosa." The remainder of the growth was then entirely fulgurated. On July 15, 1952, specimens were taken from the trigone by biopsy, even though no abnormality was seen. The areas chosen were 0.5 cm. proximal to the vesical neck in the midline, and on the right side of the trigone, just distal to the ureteral orifice. The histological sections were read as follows: Sections revealed small fragments of mucosa from the urinary bladder. The epithelium was uniformly of the transitional type. There were no significant abnormalities of the lamina propria. Diagnosis: Normal vesical mucosa. On .July 22, 1952, the patient was placed on premarin, 2.5 mg. a day. On August 12, 1952, cystoscopy ,vas repeated. On the trigone in the midline, just proximal to the vesical neck, was a 3 mm., raised, white patch, with a fairly definite edge. Another patch similar to the above was present on the left side, just distal to the left ureteral orifice. Specimens ,vere taken by biopsy, and the histological sections revealed the following:
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CHARLES NEY AND JOSEPH C. EHRLICH
A
~-
FIG. 4. Case 3. A, biopsy of trigone. Area completely covered by squamous epithelium of trigonal type. Patient had been on estrogenic therapy 3 weeks. B, biopsy of trigone after 2 years of almost continuous estrogenic therapy.
SQUAMOUS EPITHELIUM IN TRIGONE
817
Most of the surface was covered by squamous epithelium of the trigonal type. A few areas, however, were covered by transitional epithelium. The squamous epithelium was eight to twenty layers in -width, and the superficial cells contained large perinuclear clear areas. Diagnosis: Fragments of vesical mucosa containing foci of squamous epithelium of the trigonal type (fig. 4, A). Cystoscopies -were performed at regular intervals -with similar findings as aforementioned. She came to the office on April 6, 1954, and stated that she had taken premarin continuously until approximately 5 weeks ago. Cystoscopy revealed, just -within the vesical neck, several white patches, measuring 3 by 5 rnm. Specimens were taken by biopsy. The histological findings follow: One of the fragments was covered by transitional epithelium. The others were completely covered by squamous epithelium of the trigonal type. The foci of squamous epithelium were arranged in mosaic fashion. These foci were larger than those in the previous specimen. There were more layers of cells, and the perinuclear clear zones were more conspicuous indicating greater amounts of glycogen; this was confirmed by special stains. There appeared to be a slight degree of surface keratinization. In other areas of the same specimen, perinuclear clear areas were less conspicuous. Diagnosis: Fragments of mucosa from the trigone containing foci of squamous epithelium of the trigonal type (fig. 4, B). She was placed on premarin, 2.5 mg. orally, 3 times a week and 50,000 units of
FIG. 5. Case 3. Same case as figure 4. Biopsy after 16 days of supplementation of estrogen therapy with vitamin A. Area completely covered by squamous epithelium of tri_gonal type. Note appearance of keratinization in superficial cells above at left and suggestwn of intra-epithelial cornification above, at right.
818
CHARLES NEY AND JOSEPH C. EHRLICH
vitamin A2 1 • 22 orally per day. On April 22, 1954, cystoscopy was repeated and the patches on the trigone were the same as previously described. Biopsies were taken from just within the vesical neck. The histological findings were similar to those 16 days previously. Diagnosis: Fragments of vesical mucosa c01~taining foci of squamous epithelium of the trigonal type (fig. 5). Sections of specimens from this case were examined for alkaline phosphatase ;23 there was none found in the epithelium.* GENERAL SUMMATION OF HISTOLOGICAL FEATURES OF SQUAMOUS EPITHELIUM IN THE HUMAN FEMALE TRIGONE
Histological sections of these areas reveal stratified epithelium of the squamous type with certain special features. The large cells in the upper layers are polyhedral in form and contain a small, dark nucleus, surrounded by a large perinuclear clear space; the latter, in special stains, is found to have a rich content of glycogen. The nuclei are clearly visible all the way to the surface. There are no intercellular bridges; however, the large clear cells in the superficial layers appear to be separated from one another by an interlacing system of "canals" of uniform width with thin, brightly staining walls closely applied to or forming part of the cell membrane (fig. 1). "Intra-epithelial cornification" has been described and has been considered similar to that observed in the vaginal mucosa by Dierks 24 and Smith. 25 The squamous epithelium in the trigone is broader than the transitional epithelium of the urinary bladder and is characteristically arranged in tiny, disc-shaped plaques, which are closely apposed to one another in mosaic fashion (figs. 1, A, 2, A, 4, A, 4, B, 5). Occasionally, these plaques are connected by narrow bridges of transitional epithelium (fig. 1, A). The result is a distinctive festooned or scalloped contour of the basal layer of cells in relation to the lamina propria. It is this last feature which distinguishes the squamous epithelium of the human female trigone from vaginal mucosa. We have designated this epithelium "squamous epithelium of the trigonal type" because of the special characteristics mentioned. SUMMARY AND CONCLUSIONS
Observations are reported on three women, who presented distinctive grayishwhite patches on the trigone of the urinary bladder. The histological appearance of all these areas was that of squamous epithelium. Our study of extensive postmortem and surgical material confirms the contention of Cifuentes12 that foci of squamous epithelium constitute an anatomi21 McCullough, K. and Dalldorf, G.: Epithelial metaplasia: An experimental study. A.M.A. Arch. Path., 24: 486-496, 1937. 22 Thorberg, J. V.: On the influence of oestrogenic hormones on the male accessory genital system. Acta Endocrinol., Suppl. 2, 1-214, 1948. 23 Bern, H. A.: Alkaline phosphatase activity in epithelial metaplasia. Cancer Res., 12: 85-91, 1952. * These studies were kindly performed by Dr. Max Wachstein. 24 Dierks, K.: Der normale mensuelle Zyklus der menschlichen Vaginal-Schleimhaut. Arch. Gynak., 130: 46-69, 1927. 25 Smith, B. G.: Histological changes in the epithelium of the human vagina correlated with the menstrual cycle. Anat. Rec., 43: 317-332, 1929.
SQUAMOUS EPITHELIUM IN TRIGONE
819
cally distinctive feature of the human female trigone. Cystoscopic observations by one of us (C. N.) suggest that increased and/or prolonged therapy ,Yith estrogens may expand these foci; conversely, they may diminish in size after cessation of estrogenic therapy. The presence of presumably estrogen-sensitive squamous epithelium in the trigone has to be evaluated in relation to the changes in exfoliated cells in the urine during pregnancy26 and the menstrual cycle. 27 · 28 · 29 It is of practical value for the cystoscopist to be aware that the grayish-white patches on the trigone herein described occur normally in the human female trigone and are composed of squamous epithelium. The distinguishing histological characteristics of this epithelium are described; the designation, "squamous epithelium of the trigonal type" is suggested. 26 Papanicolaou, G. X.: Diagnosis of pregnancy by cytologic criteria in catheterized urine. Proc. Soc. Exper. Biol. & Med., 67: 247-249, 1948. 27 Biot, R. and Nunez, R. B.: Modificaciones Peri6dicas de! Sedimento Urinario en Relacion con el Cicio :VIenstrual. Su Posible Aplicacion Como Test de Ovulacion. La Seman a Medica, 51: 532-535, 1944. 28 Enrique, B. Del Castillo, Joaquin Argonz, and Carlos Galli Mainini: Cytologieal cycle of the urinary sediment and its parallelism with vaginal cycle. J. Clin. Enclocrinol., 8: 76-87, 1948. 29 McCallin, P. F., Taylor, E. S. and Whitehead, R. W.: A study of the changes in the cytology of the minary sediment dming the menstrual cycle and pregnancy. Am. J. Obst. & Gynec., 60: 64-74, 1950.
Vol. 73_ No. 5, May 1955 Printed in U.S.A.
SQUAMOUS EPITHELIUM IN THE TRIGONE OF THE HUMAN FEMALE URINARY BLADDER WITH A NOTE ON CYSTOSCOPIC OBSERVATIONS DURING ESTROGEN THERAPY
CHARLES NEY
AND
JOSEPH C. EHRLICH
From the Surgical Service and Department of Laboratories, Lebanon Hospital, New York, N. Y.
For many years, observers1, 2 , 3 , 4 , 5 • 6 , 7 , 8 • 9 • 10 have recognized the occurrence on the trigone of the human female bladder of grayish-white patches which have been described as chronic trigonitis, pseudomembranous trigonitis, trigonitis areata alba, etc. Cifuentes 11 • 12 clarified the nature of these patches; he noted that histologically they were composed of squamous epithelium and stated that they occurred exclusively in the trigonal mucosa of females. He stressed the resemblance to vaginal mucosa. The patches under consideration occur on the trigone of females most frequently during their active sex life; their frequency appears to diminish with age, but we have observed them in the sixth, seventh and eighth decades. Such areas have never been reported in prepubertal females or in infants; hmvever, one of us (J. C. E.) observed one such area in serial sections of the trigone of a newborn female infant. Grayish-white patches similar to those which occur in the female have rarely been described in males. Cifuentes12 had never seen one in a male, and Heymann13 reported their absence in five men studied. It should be emphasized that we are not concerned here with squamous metaplasia due to calculi, tumors, ulcers and trauma. In a routine study of five hundred consecutive autopsies of both sexes and all age groups, the present authors have not observed squamous patches of this type in a single male. This study was aided by a grant from the Aaron W. Davis Foundation. Read at annual meeting, American Urological Association, New York, K. Y. June 3, 1954. 1 Pelouze, P. S.: Trigonitis area ta alba. Surg., Gynec. & Obst., 39: 510, 1924. 2 Ryall, E. C.: Pseudomembranous trigonitis. Brit. J. Urol., 1: 255-257, 1929. 3 Orr, L.: Chronic pseudomembranous trigonitis. South. Med. J., 26: 359-361, 1933. 4 Pelouze, P. S.: Obscure pseudomembranous trigonitis. Trigonitis areata alba. Ann. Surg., 101: 594-598, 1935. 5 Fowler, H. A.: Pseudomembranous trigonitis with observations of bladder dysfunction in the female" Urol. & Cutan. Rev., 40: 156-163, 1936. 6 Douglass, H. L.: Chronic trigonitis: Its effect on trigonal epithelium. J. Tenn. l\Ied. A., 33: 261-267, 1940. 7 Douglass, H. L., Ransom, B. S. and Webster, B. H.: Some further studies on trigonitis. J. Tenn. Med. A., 25: 254-259, 1942. 8 Cifuentes, L.: Estudios sobre las trigonitis. Rev. clin. espan., 11: 171-177, 1943. 9 Matheson, N. M.: Some diseases of the female urinary bladder. Tr. M. Soc. London, 64: 117-127, 1943-46. 10 Brown, H. E.: Chronic urethrotrigonitis in the female. Pennsylvania Med. J., 53: 489-493, 1950. 11 Cifuentes, L.: Epitelio de tipo vaginal en la vejiga urinaria de Ia mujer. Rev. clin. espan., 20: 54-56, 1946. 12 Cifuentes, L.: Epithelium of vaginal type in the female trigone. The clinical problem of trigonitis. J. Urol., 57: 1028-1037, 1947. 13 Heymann, A.: Die Cystitis Trigoni Chronica der Frau und ihre pathologische Anatomie. Beitrage zur Metaplase des Blasenepithels. Centralblatt for die Krankheiten der Harn und Sexual-Organe, 17: 177-192, 1906.
809
810
CHARLES NEY AND JOSEPH C. EHRLICH
The presumed origin14 of these patches in the female from epithelium of the urogenital sinus suggested the possibility that these foci in the urinary bladder might respond to estrogenic stimulation in a fashion similar to the well-known response of related mucosa in the reproductive tract. Reports15 • 16 • 17 • 18 , 19 • 20 of results of experiments in animals strengthen this hypothesis. As far as can be ascertained, there are no reports indicating direct evidence of histological changes in the mucosa of the human urinary bladder following estrogenic stimulation. The following is a report of three cases in which changes in squamous patches in the mucosa of the trigone in women appeared to be related to the administration of estrogenic substances. CASE REPORTS
Case 1. M. N., a 33 year old white woman, presented herself on September 12, 1949 with the chief complaints of difficulty of urination, frequency of urination, and pain following urination for 2 years. In September 1936, a partial resection of a cystic left ovary had been performed. In January 1939, the left tube, the remainder of the left ovary, and the right tube had been removed; the transcript of the findings at this operation stated that the right ovary was absent. One month before this latter operation, menopausal symptoms consisting of flushes, weakness, and nervousness began; these have continued until the present, although they are now somewhat less severe. The general physical examination of September 12, 1949 was essentially negative. Urine examination revealed no abnormalities. Observation cystoscopy revealed a granular urethritis and a mild stenosis of the external urethral meatus. The bladder appeared normal. After a few dilatations of the urethra, the patient did not return; she was not seen again until October 1951. At that. time, many cysts of the neck of the bladder were found on cystoscopy. The mucosa of the bladder, including the t.rigone, was normal. She was admitted to Lebanon Hospital on December 11, 1951. Culture of the urine was sterile. The cysts in the neck of the bladder from 9 to 3 o'clock were fulgurat.ed under pent.othal sodium anesthesia on December 12, 1951. At the same time, specimens of the trigone of the bladder were taken by biopsy, although no abnormalities could be seen. The report of the histological findings follows : Sections revealed small fragments of mucosa from the urinary bladder. The 14 Zuckerman, S.: The histogenesis of tissues sensitive to oestrogens. Biol. Rev., 15: 231-271, 1940. _ 15 Lacassagne, A.: Modifications de L'Epithelium Vesical Chez La Souris Atteinte de Retention Urinaire a La Suite d'Injections d'Oestrone. Comptes Rendus Hebdomadires des Seances et Memoires de La Societe de Biologic, 120: 833-855, 1935. 16 Raynaud, A.: Modifications Apportees Precocement Dans La Structure de La Vessie etde L'Uretre du Chat Par Des Injections de Dihydrofolliculine. Comptes Rendus Hebdomadiares des Seances et Memoires de La Societe de Biologic, 126: 215--217, 1937. 17 Burns, R. K., Jr.: Effects of female sex hormones in young opossums. Proc. Soc. Exper. Biol. & Med., 41: 270-272, 1939. 18 Burns, R. K., Jr.: Sex differentiation during the early pouch stage of the opossum (Didelphys Virginiana) and a comparison of the anatomical changes induced by male and female sex hormones. J. Morphol., 65: 497-548, 1939. 19 Burns, R. K., Jr.: Origin and differentiation of epithelium of urogenital sinus in the opossum. Proc. Soc. Exper. Biol. & Med., 47: 106-108, 1941. . 20 Moore, C.R.: On the role of sex hormones in sex differentiation in the opossum (Didelphys Virginiana). Physiol. Zool., 14: 1-47, 1941.
SQUAMOUS EPITHELIUM IN TRIGONE
811
epithelium was uniformly of the transitional type with flattened surface cells. There were no significant abnormalities of the lamina propria. Stains for glycogen revealed minimal amounts in the basal layer of the epithelium. Diagnosis: N onnal mucosa of urinary bladder. The patient was discharged from the hospital on December 13, 1951. Therapy with premarin (2.5 mg. daily, orally) was begun on December 21, 1951. On January 4, 1952, a cystoscopy was performed in the office, and at this time four grayish-white, raised, granular patches could be seen on the trigone of the bladder, varying in diameter from 3-5 mm. Two of these were situated near the vesical neck to the right and left of the midline. Two others were situated just distal to the right and left ureteral orifices. There were a few cysts still present on the neck of the bladder between 5 and 7 o'clock. Premarin was taken without interruption until admission to Lebanon Hospital on .January 14, 1952. On January 15, 1952, under pentothal sodium anesthesia, specimens of the grayish-white patches on the trigone were taken by biopsy. The cysts of the vesical neck were now thoroughly fulgurated. The report of the histological findings follows: Sections revealed fragments of mucosa from the urinary bladder containing areas of squamous epithelium. The latter was focal in distribution; the intervening epithelium was of the transitional type. The squamous epithelium vrns six to fifteen layers in width, and the superficial cells contained large perinuclear clear areas in which considerable amounts of glycogen were demonstrated by special stains. Foci of parakeratosis were noted. There appeared to be slight intraepithelial comification. The lamina propria showed vascular engorgement and a slight infiltration by lymphocytes. Diagnosis: Fragments of vesical mucosa containing foci of squamous epithelium of the trigonal type (fig. 1). Case 2. F. C., a white woman, 44 years of age, was first seen on December 8, 1950. Her chief complaint was increasing frequency of urination for 6 months; recently she had been voiding every half hour. One month previously (N ovember, 8, 1950) her family physician had started her on premarin, 1.25 mg. daily orally because she had been complaining of hot flushes, nervousness and dizziness. The patient had had a vaginal hysterectomy with a perineorrhaphy 10 years ago when she was thirty-four. The ovaries had not been removed. General physical examination disclosed essentially normal findings. Urine examination (catheterized specimen) showed only a rare leukocyte. On December 14, 1950, a cystoscopy was performed in Lebanon Hospital. A few cysts were present in the neck of the bladder, but the urethra, trigone and rest of the bladder showed no abnormalities. Cultures of urine from bladder and both kidneys were sterile. Due to a questionable finding in the left pyelogram, it was decided to repeat the cystoscopy after an interval of several months. The patient had been taking premarin continuously for nearly 4 months; it had been stopped on March 1, 1951. A cystoscopy was performed on March 8, 1951. A left retrograde pyelogram was considered normal. A grayish-white, raised patch was observed on the trigone proximal to the neck of the bladder and distal to the right ureteral
812
CHARLES NEY AND JOSEPH C. EHRLICH
I'
FIG. 1. Case 1. A, biopsy of trigone. Characteristic foci of squamous epithelium of trigonal type arranged in tiny plaques, some of which are connected by narrow bridges of transitional epithelium. Note festooned contour to basal zone of epithelium with intervening projections of lamina propria resembling papillary zone of dermis. Patient had been on estrogenic therapy. B, selected area from A at higher magnification to show gradual change in polarity from basal to superficial polyhedral cells. N" ote large, perinuclear clear areas and intercellular "canals."
SQUAMOUS EPITHELIUM IN TRIGONE
813
orifice. It was about 5~7 mm. in dianieter, smooth and glistening in appearance. A specimen was taken by biopsy from this area. The report of the histological findings follows: Section revealed a fragment of mucosa from the urinary bladder. The lamina propria was covered by broad epithelium of the squamous type. The basal zone of the epithelium consisted of compactly arranged cells with dark nuclei, and was two to four layers in width. The polyhedral layer was three to eight rows in width, and many of these cells had large perinuclear, clear areas whose appearance suggested the presence of glycogen; this was confirmed by special stains. Normal epithelium of the transitional type did not appear in the specimen. Diagnosis: Fragments of vesical mucosa; epithelium entirely of squamous trigonal type (fig. 2, A). The patient took no more estrogenic substances after March 1, 1951. She was readmitted to Lebanon Hospital on July 9, 1951. On July 12, 1951, cystoscopy was done under general anesthesia. Although no patch was seen in the trigone, five specimens were obtained by biopsy in the vicinity of the previous lesion. The report of the histological findings follows: Sections revealed fragments of mucosa from the urinary bladder with foci of squamous epithelium appearing as patches or islands in otherwise normal transitional epithelium. These squamous foci were thinner than those in the specimen of March 7, 1951. The basal zone had two to four layers of cells, and the polyhedral layer also had two to four rows. Perinuclear vacuolization was much less conspicuous. Stain for glycogen disclosed minute amounts in the transitional epithelium; squamous foci did not appear in the fragments which had been placed in special fixative for glycogen stains. There was inflamn1ation of the lamina propria. Diagnosis: Fragments of mucosa from the urinary bladder showing a few relatively thin foci of squamous epithelium (fig. 2, B). Therapy with premarin, 1.25 mg. daily, orally was reinstituted on July 24, 1951, and was continued until re-admission to Lebanon Hospital on October 31, 1951. On November 1, 1951, a cystoscopy ·was performed. A raised, grayishwhite, smooth, glistening mound, 3 mm. in diameter was observed in the same region as the original lesion. Specimens were taken from this area. The report of the histological findings follows: The section consisted of three fragments of tissue from. the urinary bladder. One of these was covered by relatively normal transitional epithelium. A second was covered partly by transitional and partly by squamous epithelium. A third fragment was covered entirely by squamous epithelium. The appearance of the squamous area was similar to that in the first specimen taken about eight months previously. Diagnosis: Fragments of mucosa from the urinary bladder containing foci of squamous epithelium of the trigonal type (fig. 3). Case 3. M. B., a 49 year old white woman, came to the office on April 23, 1952, complaining of hematuria of 5 days' duration. The past history was noncontributory, except that for 2 years she had been going through the menopause and complaining of hot flushes, nervousness and irregular menstruation. Physical examination was essentially negative. Cystoscopy was performed at the office
814
CHARLES NEY AND JOSEPH C. EHRLICH
,!it.
FIG. 2. Case 2. A, biopsy of trigone. Area illustrated is entirely covered by squamous epithelium of trigonal type. Patient had been on estrogenic therapy 4 months. B, biopsy of trigone 4 months after cessation of estrogenic therapy. Area illustrated covered partly by transitional and partly by thinned out squamous epithelium. Inflammation of lamina propria.
SQUAMOUS EPITHELIU!VI IN 'J'RIGONE
815
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·• - .•
ti,;
'' Fm. 3. Case 2. Same case as figure 2. Biopsy of trigone 3 months and 7 days after resumption of estrogenic therapy. Area illustrated covered entirely by squamous epithelium of trigonal type. Superficial layers of cells are compact, flattened, nonvacuobted ,Yith persistent nuclei and present appearance of parakeratosis.
and again in the hospital the following day. Just lateral to the right ureteral orifice was a 2~3 mm., papillomatous growth, with a thin stalk, The trigone was normal, Upper tracts were normal, and there -rrns no growth on culture from either kidney or bladder. The patient was anesthetized with intravenous sodium pentothaL A specinien of the growth was taken by biopsy. The histopathological report was, "Fragments of papilloma of the urinary bladder; fragments of inflamed vesical mucosa." The remainder of the growth was then entirely fulgurated. On July 15, 1952, specimens were taken from the trigone by biopsy, even though no abnormality was seen. The areas chosen were 0.5 cm. proximal to the vesical neck in the midline, and on the right side of the trigone, just distal to the ureteral orifice. The histological sections were read as follows: Sections revealed small fragments of mucosa from the urinary bladder. The epithelium was uniformly of the transitional type. There were no significant abnormalities of the lamina propria. Diagnosis: Normal vesical mucosa. On .July 22, 1952, the patient was placed on premarin, 2.5 mg. a day. On August 12, 1952, cystoscopy ,vas repeated. On the trigone in the midline, just proximal to the vesical neck, was a 3 mm., raised, white patch, with a fairly definite edge. Another patch similar to the above was present on the left side, just distal to the left ureteral orifice. Specimens ,vere taken by biopsy, and the histological sections revealed the following:
816
CHARLES NEY AND JOSEPH C. EHRLICH
A
~-
FIG. 4. Case 3. A, biopsy of trigone. Area completely covered by squamous epithelium of trigonal type. Patient had been on estrogenic therapy 3 weeks. B, biopsy of trigone after 2 years of almost continuous estrogenic therapy.
SQUAMOUS EPITHELIUM IN TRIGONE
817
Most of the surface was covered by squamous epithelium of the trigonal type. A few areas, however, were covered by transitional epithelium. The squamous epithelium was eight to twenty layers in -width, and the superficial cells contained large perinuclear clear areas. Diagnosis: Fragments of vesical mucosa containing foci of squamous epithelium of the trigonal type (fig. 4, A). Cystoscopies -were performed at regular intervals -with similar findings as aforementioned. She came to the office on April 6, 1954, and stated that she had taken premarin continuously until approximately 5 weeks ago. Cystoscopy revealed, just -within the vesical neck, several white patches, measuring 3 by 5 rnm. Specimens were taken by biopsy. The histological findings follow: One of the fragments was covered by transitional epithelium. The others were completely covered by squamous epithelium of the trigonal type. The foci of squamous epithelium were arranged in mosaic fashion. These foci were larger than those in the previous specimen. There were more layers of cells, and the perinuclear clear zones were more conspicuous indicating greater amounts of glycogen; this was confirmed by special stains. There appeared to be a slight degree of surface keratinization. In other areas of the same specimen, perinuclear clear areas were less conspicuous. Diagnosis: Fragments of mucosa from the trigone containing foci of squamous epithelium of the trigonal type (fig. 4, B). She was placed on premarin, 2.5 mg. orally, 3 times a week and 50,000 units of
FIG. 5. Case 3. Same case as figure 4. Biopsy after 16 days of supplementation of estrogen therapy with vitamin A. Area completely covered by squamous epithelium of tri_gonal type. Note appearance of keratinization in superficial cells above at left and suggestwn of intra-epithelial cornification above, at right.
818
CHARLES NEY AND JOSEPH C. EHRLICH
vitamin A2 1 • 22 orally per day. On April 22, 1954, cystoscopy was repeated and the patches on the trigone were the same as previously described. Biopsies were taken from just within the vesical neck. The histological findings were similar to those 16 days previously. Diagnosis: Fragments of vesical mucosa c01~taining foci of squamous epithelium of the trigonal type (fig. 5). Sections of specimens from this case were examined for alkaline phosphatase ;23 there was none found in the epithelium.* GENERAL SUMMATION OF HISTOLOGICAL FEATURES OF SQUAMOUS EPITHELIUM IN THE HUMAN FEMALE TRIGONE
Histological sections of these areas reveal stratified epithelium of the squamous type with certain special features. The large cells in the upper layers are polyhedral in form and contain a small, dark nucleus, surrounded by a large perinuclear clear space; the latter, in special stains, is found to have a rich content of glycogen. The nuclei are clearly visible all the way to the surface. There are no intercellular bridges; however, the large clear cells in the superficial layers appear to be separated from one another by an interlacing system of "canals" of uniform width with thin, brightly staining walls closely applied to or forming part of the cell membrane (fig. 1). "Intra-epithelial cornification" has been described and has been considered similar to that observed in the vaginal mucosa by Dierks 24 and Smith. 25 The squamous epithelium in the trigone is broader than the transitional epithelium of the urinary bladder and is characteristically arranged in tiny, disc-shaped plaques, which are closely apposed to one another in mosaic fashion (figs. 1, A, 2, A, 4, A, 4, B, 5). Occasionally, these plaques are connected by narrow bridges of transitional epithelium (fig. 1, A). The result is a distinctive festooned or scalloped contour of the basal layer of cells in relation to the lamina propria. It is this last feature which distinguishes the squamous epithelium of the human female trigone from vaginal mucosa. We have designated this epithelium "squamous epithelium of the trigonal type" because of the special characteristics mentioned. SUMMARY AND CONCLUSIONS
Observations are reported on three women, who presented distinctive grayishwhite patches on the trigone of the urinary bladder. The histological appearance of all these areas was that of squamous epithelium. Our study of extensive postmortem and surgical material confirms the contention of Cifuentes12 that foci of squamous epithelium constitute an anatomi21 McCullough, K. and Dalldorf, G.: Epithelial metaplasia: An experimental study. A.M.A. Arch. Path., 24: 486-496, 1937. 22 Thorberg, J. V.: On the influence of oestrogenic hormones on the male accessory genital system. Acta Endocrinol., Suppl. 2, 1-214, 1948. 23 Bern, H. A.: Alkaline phosphatase activity in epithelial metaplasia. Cancer Res., 12: 85-91, 1952. * These studies were kindly performed by Dr. Max Wachstein. 24 Dierks, K.: Der normale mensuelle Zyklus der menschlichen Vaginal-Schleimhaut. Arch. Gynak., 130: 46-69, 1927. 25 Smith, B. G.: Histological changes in the epithelium of the human vagina correlated with the menstrual cycle. Anat. Rec., 43: 317-332, 1929.
SQUAMOUS EPITHELIUM IN TRIGONE
819
cally distinctive feature of the human female trigone. Cystoscopic observations by one of us (C. N.) suggest that increased and/or prolonged therapy ,Yith estrogens may expand these foci; conversely, they may diminish in size after cessation of estrogenic therapy. The presence of presumably estrogen-sensitive squamous epithelium in the trigone has to be evaluated in relation to the changes in exfoliated cells in the urine during pregnancy26 and the menstrual cycle. 27 · 28 · 29 It is of practical value for the cystoscopist to be aware that the grayish-white patches on the trigone herein described occur normally in the human female trigone and are composed of squamous epithelium. The distinguishing histological characteristics of this epithelium are described; the designation, "squamous epithelium of the trigonal type" is suggested. 26 Papanicolaou, G. X.: Diagnosis of pregnancy by cytologic criteria in catheterized urine. Proc. Soc. Exper. Biol. & Med., 67: 247-249, 1948. 27 Biot, R. and Nunez, R. B.: Modificaciones Peri6dicas de! Sedimento Urinario en Relacion con el Cicio :VIenstrual. Su Posible Aplicacion Como Test de Ovulacion. La Seman a Medica, 51: 532-535, 1944. 28 Enrique, B. Del Castillo, Joaquin Argonz, and Carlos Galli Mainini: Cytologieal cycle of the urinary sediment and its parallelism with vaginal cycle. J. Clin. Enclocrinol., 8: 76-87, 1948. 29 McCallin, P. F., Taylor, E. S. and Whitehead, R. W.: A study of the changes in the cytology of the minary sediment dming the menstrual cycle and pregnancy. Am. J. Obst. & Gynec., 60: 64-74, 1950.