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RETROVESICAL MASS IN MEN: PITFALLS OF DIFFERENTIAL DIAGNOSIS
OO22-5347#9/16 14-1244/0
Val. 161, 1244-1248. April 1999 Printed in U.S.A.
THEJOLXVALOF UROLOGY Copyright 0 1999 by A~~ERIcAN UROL~CICAL k.J.ocuTlon. IRC
RETROVESICAL MASS IN MEN: PITFALLS OF DIFFERENTIAL DIAGNOSIS STEFAN E. DAHMS, MARKUS HOHENFELLNER, m R G E N F. LINN, CHRISTIAN EGGERSMA", GERALD HAUPT AND JOACHIM W. THUROFF From the Department of Urolog.v, Johannes Gutenberg University, School of M e d i c i ~ Mainz, , Department of Urology and Pediatric Urology, Uniuerstty of Witten JHerdecke, School of Medicine, Klinikum Barmen, Wuppertal and Department of Urology, Ruhr University. School of Medicine, Heme, Germany
ABSTRACT
Purpose: We review the differential diagnosis and treatment of retrovesical masses in men. Materials and Methods: During the last 8 years 21 male patients 3 to 79 years old (mean age 47.1) presented with symptoms or signs of a retrovesical mass. Clinical features and diagnostic findings were reviewed, and related to surgical and histopathological findings. Results: The retrovesical masses included prostatic utricle cyst in 3 cases, prostatic abscess in 1, seminal vesicle hydrops in 6, seminal vesicle cyst in 2, seminal vesicle empyema in 3, large ectopic ureterocele in 1, myxoid liposarcoma in 1, malignant fibrous histiocytoma in 1, fibrous fossa obturatoria cyst in 1, hemangiopericytoma in 1 and leiomyosarcoma in 1. In 17 patients various symptoms were seen and in 4 the mass was incidentally detected. A mass was palpable on digital rectal examination in 16 cases and visible on sonography in 20. For a cystic mass medial location relative to the bladder neck was suggestive of prostatic abscess or utricle cyst, while lateral location was suggestive of seminal vesicle cysthydrops or empyema, ectopic ureter or ureterocele. In 6 patients diagnosis was established only by exploratory laparotomy and histopathological examination. Conclusions: Digital rectal examination and sonography reliably detect a retrovesical mass. Nevertheless, clinical signs and median or lateral location relative to the bladder neck on ultrasound are diagnostic only for cystic lesions. Computerized tomography and magnetic resonance imaging are useful for staging malignant tumors. However, needle or open biopsy is required in most cases to establish a histopathological diagnosis. Exploratory laparotomy and histopathological examination are the procedures of choice when other findings are equivocal. KEYWORDS:diagnosis, treatment outcome, prostate, seminal vesicle
A retrovesical mass that is not related to benign prostatic hyperplasia (BPH) or prostate cancer is uncommon in man. Since 1872 retrovesical cystic structures have stimulated interest in embryology and anatomy of these pathological entities-3 Although modern imaging techniques have increased the diagnostic yield, cystic and solid retrovesical masses still present a diagnostic dilemma. The rarity of these lesions limits clinical experience, and symptoms may mimic other more common diseases of the lower urinary tract. Retrovesical masses may, if at all, influence function of the pelvic organs in various ways and many possible etiologies must be considered. We retrospectively identified characteristic diagnostic features for differential diagnosis of a retrovesical mass.
were available. CT and MRI were evaluated by radiologists who also knew the results of the history, digital rectal examination and ultrasound. CT was performed without and if possible (no history of allergy to contrast medium, normal serum creatinine) with contrast medium, while transabdominal MRI T1 and T2 sequences were obtained with and without gadolinium pentetic acid. Open and endoscopic surgery was performed in 14 and 4 cases, respectively. Of the 3 untreated patients 2 had an asymptomatic seminal vesicle cysthydrops and 1 had a malignant fibrous histiocytoma but died of acute myocardial infarction before surgery. Histopathological examination of the retrovesical masses was performed in all patients and related to the preoperative findings.
PATIENTS AND METHODS
RESULTS
From 1989 to 1997, 21 male patients 3 to 79 years old (mean age 47.1) with retrovesical mass were seen at our institutions. Medical records were reviewed with special attention to clinical presentation, diagnostic tests, operative findings and histopathological diagnosis. History, physical examination, urinalysis, blood cell counts and serum chemistry studies were obtained in all patients. Imaging studies included transvesical ultrasound in 21 cases, excretory urography in 17, urethrocystoscopy in 14, computerized tomography (CT) in 14 and magnetic resonance imaging (MRI) in 14. History, digital rectal examination and ultrasound were performed by urologists and, therefore, all data Accepted for publication November 20, 1998.
Clinical profile. Clinical findings are summarized in the table. Of the 21 patients 17 presented with acute ( 8 ) or chronic (9) symptoms, and in 4 the mass was asymptomatic and found incidentally. Acute symptoms were inflammatory, such as fever with or without flank pain, in 5 patients and noninflammatory, such as urinary retention in 3. In contrast, 9 patients had chronic symptoms, such as perineal pain, frequency, recurrent epididymitis and urinary incontinence. Retrovesical masses were classified by origin as prostatic in 5 cases, seminal vesicle in 11, ureteral in 1 and connective tissue in 4. Digital Rectal Examination: Intraprostatic lesions were noted in 4 of 5 patients with a prostatic mass and asymmetric
1244
RETROVESICAL MASS IN MEN
1245
Classification of retrovesical masses Case - Pt. No. Age
Symptoms
Digital Examination
Diagnostic Procedure
1 - 39
Chronic perineal pain
Intraprostatic lesion
2 - 47
Acute urinary retention
Extraprostatic asymmetric mass
3-69
Painful micturition, fever, perineal pain Chronic painful micturition Chronic perineal pain
Intraprostatic lesion
Extraprostatic asymmetric mass Extraprostatic asymmetric mass Extraprostatic asymmetric mass
Ultrasound,' IVP,urethrocystoscopy* Ultrasound, Tvp, CT,* MRI,* exploratory laparotomy* Ultrasound,* IVP,CT,* urethrocystoscopy* Ultrasound,' IVP,MRI,* urethrocystoscopy Ultrasound,* IVP,MRI," urethrocystoscopy* Ultrasound,* IVP,CT*
4-55 5-
19
Intraprostatic lesion Intraprostatic lesion
7 - 60
Painful micturition, fever, flank pain Fever, urosepsis
8 - 62
None
9 - 69
Acute urinary retention
Extraprostatic asymmetric mass
10 - 50
Fever, flank pain
11 - 50
Chronic frequency
Extraprostatic asymmetric mass Extraprostatic asymmetric mass
12 - 25
Recurrent epididymitis
Unremarkable
13-
6-38
3
Acute urinary retention
Not performed
14 - 35
Recurrent epididymitis
Extraprostatic asymmetric mass
15 - 28
Recurrent epididymitis
16 - 44
None
Extraprostatic asymmetric mass Extraprostatic asymmetric mass
17 - 30
Recurrent epididymitis
Extraprostatic asymmetric mass
18 - 79
Urinary incontinence
Extraprostatic asymmetric mass
19 - 57
None
Unremarkable
20 - 67
Acute urinary retention
Retrorectal mass
21-63
None
Retrovesical mass
:
Ultrasound,* IVP,CT,* urethrocystoscopy Ultrasound,* IVP,MRI,* urethrocystoscopy, needle aspiration biopsy* Ultrasound, NP, uretbrocystoscopy, exploratory laparotomy* Ultrasound,* IW, radioisotope scan, CT, MRIf Ultrasound,* radioisotope scan, CT,* MRI,* urethrocystoscopy Ultrasound,* MRI,* urethrocystoscopy Ultrasound,* MRI*
Location
Diagnosis
Surgical Treatment
Prostate
Utricle cyst
Unroofing
Prostate
Myxoid liposarcoma
Prostate
Abscess
Prostate
Utricle cyst
Extirpation, cystoprostatectnmy, Mainz pouch I Unroofing and drain age Unroofing
Prostate
Utricle cyst
Unroofing
Seminal vesicle
Empyema
Extirpation
Seminal vesicle
Empyema
Extirpation
Seminal vesicle
cyst
None
Seminal vesicle
cyst
Extirpation
Seminal vesicle
Empyema
Extirpation
Seminal vesicle
Hydrops
Nephmureterectomy. vesicle extirpation
Seminal vesicle
Hydmps
Seminal vesicle
Hydrops
Nephroureterectomy, vesicle extirpation Nephmuretereetomy, vesicle extirpation Nephroureterectomy, vesicle extirpation
Ultrasound,* IW, Seminal vesicle radioisotope scan, CT,* urethrocystoscopy* Ultrasound,* IVP,radioSeminal vesicle isotope scan, CT,* MRI* Ultrasound,* IVF', radioSeminal vesicle isotope scan, CT,* MRI,* needle aspiration biopsy* Ultrasound, IVP,radioiso- Ureter tope scan, CT, MRI, urethrocystoscopy, explora t o j laparotimy* Ultrasound, M', CT, Connective tissue MRI, urethrocystoscopy, needle biopsy' Ultrasound, IVP,CT, Connective tissue MRI, urethrocystoscopy, exploratory laparotomy* Ultrasound, CT, MRI, exConnective tissue ploratory laprotomy* Ultrasound, NP,CT, ureConnective tissue throcystoscopy, needle biopsy, exploratory laparotornv*
Hydrops Hydrops Hydrops
Nephroureterectomy, vesicle extirpation None
.
Ectopic uretero cele
Nephroureterectomy ureterocele extirpation
Malignant fibrous histiocytoma
None (died of acute myocardial infarction) Extirpation
Fibrous fossa obturatoria cyst Hemangiopericytoma Leiomyosarcoma
Extirpation Extirpation
* Guiding diagnostic procedure.
extraprostatic masses were detected in 8 of 11with a seminal vesicle mass. The patient with a ureteral mass had a large mobile extraprostatic tumor. In addition, digital rectal examination revealed connective tissue masses in 1patient with a large asymmetric extraprostatic mass, 1 with a retrorectal tumor and 1 with a retrovesical mass 2 years after radical prostatectomy for margin positive prostate cancer. Urinalysis: Urinalysis demonstrated leukocyturia and m i c n hematuria in all cases of prostatic and seminal vesicle masses except those with asymptomatic seminal vesicle c y s t h y ~ p s . Urine leukocytes and white blood count were significantly higher for a prostatic abscess or seminal vesicle empyema than for a simple prostatic utricle and seminal vesicle cyst. Urindysis and blood count were normal in the case of ureteral mass. Microhematuria was present in the 3 patients with retrovesical connective tissue masses when digital rectal examination was suggestive of tumor. Ln the other patient with an unremarkable digital rectal examination (case 19) laboratory studies revealed no pathological findings.
Imaging studies. Ultrasound revealed cystic lesions in 16 patients and solid masses in 5. Medial locations of a cystic retrovesical mass were consistent with a prostatic utricle cyst (single small lesion in the dorsomedial aspect of the prostate, fig. 1) or abscess (multiple cavities without evidence of a preferred area, fig. 2). Additional transrectal ultrasound in 2 patients confirmed intraprostatic location of a cystic structure. Ultrasound in the patient with the myxoid liposarcoma (case 2) revealed a mass 7.5 cm. in diameter but was inconclusive regarding its relationship to neighboring structures. A cystic extraprostatic mass lateral to the bladder neck was demonstrated on ultrasound for all seminal vesicle or ureteral masses, unlike prostatic masses in medial locations, which were not visible. In 1 patient a seminal vesicle cyst was misinterpreted as BPH associated with a bladder stone. However, ultrasound correctly identified solid retrovesical connective tissue masses in all 5 cases. A nonfunctioning or absent kidney was revealed on IVP in 13 patients with seminal vesicle (ll),ureteral (1) and pros-
1246
RETROVESICAL MASS IN MEN
FIG. 1. Transrectal ultrasound (axial scan, 7.5 MHz. transducer) shows intraprostatic midline cyst in case 1.
tatic (1) masses. In the patient with a retrovesical connective tissue mass, and inconclusive digital rectal examination and laboratory tests (case 19) IVP demonstrated slight elevation of the bladder on the left side. CT and/or MRI accurately depicted prostatic utricle cysts, intraprostatic abscess cavities and a pelvic mass (case 2 , fig. 3), as well as seminal vesicle cystdhydropses and empyemas. However, CT diagnosed the ureteral mass as a pelvic cyst. Both imaging studies failed to detect a hypoplastic kidney found intraoperatively but revealed solid retrovesical connective tissue masses in all 4 cases. However, in 2 patients (cases 18 and 20) CT misinterpreted the tumors as organized hematomas, 1 of which was misinterpreted on MRI (fig. 4). In the patient with previous radical prostatectomy for adenocarcinoma of the prostate (case 21) CT demonstrated a 10 X 8 X 10 cm. mass encompassing the bladder and rectum. Histopathological examination of needle biopsies demonstrated connective tissue and leiomyoma but no sign of malignancy. In all cases assessment relative to mass location, involvement of neighboring organs and lymph nodes was accurate. On urethrocystoscopy prostatic utricle cysts were seen as obstruction of the bladder outlet and prostatic abscess presented as a diffuse enlargement of the prostate. Compression of the posterior bladder wall and absence of the ureteral orifice were seen in patients with seminal vesicle retrovesical masses. The patient with a misleading ultrasound had extensive bladder trabeculation and an intravesical calculus suggesting bladder outlet obstruction. On urethrocystoscopy the bladder neck appeared obstructed and a ureteral orifice was absent on the ipsilateral side. Surgical management. The mass as demonstrated on preoperative imagmg studies was confirmed in all patients who underwent surgery. Prostatic utricle and seminal vesicle cysts were treated only if symptomatic. Transurethral unroofing of prostatic utricle cysts (3 cases) and drainage of the prostatic abscess were uncomplicated. Seminal vesicle cysts/ hydropses were excised when symptomatic (6 cases) as were empyemas (3)without significant morbidity. Diagnosis of the 2 asymptomatic seminal vesicle cystshydropses was established by needle aspiration biopsy, which revealed seminal fluid containing numerous spermatozoa. In 6 cases exploratory laparotomy and histopathological examination were necessary to establish diagnosis of the pelvic mass. Prostatectomy was planned in the patient in whom ultrasound had revealed no mass but was suggestive of BPH associated with a bladder stone (case 9). ARer intraoperative incision of the bladder neck approximately 300 to 400 ml. hemorrhagic fluid leaked, and subsequently a bladder stone and large seminal vesicle cyst were removed. Convalescence was uneventful.
The patient with a hypoplastic kidney found only at laparotomy (case 17) had a large ectopic ureterocele at the bladder neck. Preoperative transabdominal ultrasound demonstrated no kidney in the normal location or hypoplastic kidney in the pelvis. Transrectal ultrasound revealed a cystic structure close to the left side of the bladder neck with questionable involvement of the left seminal vesicle but no hypoplastic kidney. IVF' showed no left kidney and displacement of the bladder to the right side. Radioisotope scan was unable to demonstrate a functioning left kidney. CT and MRI depicted a cystic mass ("an approximately 3 cm. in diameter diverticulum-like structure where normally the ureter leads into the bladder") which showed enhancement with contrast medium. Seminal vesicles could be distinguished from the cystic mass without involvement. Intraoperatively a tiny hypoplastic kidney was found close to the cyst, which appeared to be a large ureterocele. Seminal vesicles and ducts showed no pathological findings, and excision of the hypoplastic kidney, ureter and ureterocele was performed. In patients with seminal vesicle hydrops (cases 11 to 15) a hypoplastic kidney and ectopic ureter originating from the seminal vesicle were found intraoperatively, and nephroureterectomy and extirpation of the seminal vesicle were performed. Convalescence was uneventful in all cases. The fossa obturatoria cyst (case 19), hemangiopericytoma (case 20) and leiomyosarcoma (case 21) were intraoperatively diagnosed by histopathological examination and excised. The patient with malignant fibrous histiocytoma died of acute myocardial infarction before surgery and histopathological evaluation was obtained by needle biopsy. The patient with the leiomyosarcoma underwent open surgery (case 21), and the 500 gm. tumor was where the prostate had been and was extirpated. The patient with intraoperatively confirmed myxoid liposarcoma of the prostate (case 2) was treated with radical cystoprostatectomy and Mainz pouch I urinary diversion without complications, and 2-year followup examination revealed no recurrence. DISCUSSION
Retrovesical masses can be classified as congenital or acquired,4,5 or according to organ specific pathology. During embryological development of the genitourinary tract the mesonephric duct (wolffian duct) and the ureteral bud join the urogenital sinus. The opening of the wolffian duct migrates medial downward, whereas the ureteral bud develops upward and lateral. The final position of these structures determines the ingrowth of mesodermal tissue, which later differentiates into the trigonal structures of the bladder. Just above and below the mesonephric duct the prostate gland develops from branching epithelial outgrowths. In male subjects the wolffian duct differentiates into the genital duct system, forming the epididymis, vas deferens, seminal vesicles and ejaculatory ducts.4 Mullerian regression factor causes regression of the mullerian duct.5 If the gonad begins t o differentiate into an ovary, the wolffian duct remains rudimentary. The mullerian duct contributes to the uterine tubes, uterus and most of the vagina. Possible reasons for various malformations, such as prostatic utricle cyst, seminal vesicle cysthydrops, ureterocele and ectopic ureter, are the close spatial relationship among the mullerian duct, wolffian duct and ureter, and defective regression of the mullerian duct. The association with other congenital disorders, such as ipsilateral agenesis of the kidney, ureter and hemitrigone, hypospadias and intersex is well recognized, and emphasizes the need for further examination of the upper urogenital tract.6-8 Retrovesical masses have no classic clinical presentation and most symptoms are nonspecific, even if the tumor is large. Duration of symptoms (acute or chronic) and location of retrovesical cystic lesions medial or lateral to the bladder
RETROVESICAL MASS IN MEN
1247
F I ~2.. Transrectal ultrasound (axial scan, 7.5 MHz. transducer) (A) and transverse CT ( B ) demonstrate multiple intraprostatic cystic cavities in case 3.
F ~ 3 .~sagittal , MRI of pelvis ( ~ 1 - ~ ~ i ~reveals h t ~ dlarge ) retrovesical mass with homogeneous signal intensity in case 2.
FIG. 4. Sa 'ttal MRI of pelvis demonstrates 10 X 17 cm. retrovesical mass Witf COmpreSSiOn but without involvement of bladder in case 20.
neck guide diagnosis (fig. 5). In contrast, since only a relatively small number of patients with solid retrovesical masses were included in our study and histopathological findings were rare, an algorithm for diagnosis of solid masses could not be developed. Chronic symptoms, such as impaired voiding, perineal pain and recurrent epididymitis, are poor diagnostic guides. Acute symptoms of sepsis with and without urinary retention or other voiding symptoms are suggestive of prostatic abscess, and prostatic utricle and seminal vesicle empyema. Various studies have demonstrated that comparison of needle biopsies with findings of surgical or autopsy specimens may present a diagnostic dilemma since detection of a mass with benign pathology does not necessarily mean that carcinoma is not also present. For example, 4 to 8%of benign prostates contain areas of grade 3 prostatic intraepithelial neoplasia and up to 68% may have foci of grade 2 prostatic intraepithelial neoplasia.9-11 Since needle biopsies are operator dependent, there is concern in uncertain cases that carcinoma is present but not detected due to sampling errors. Radiographic evaluation of retrovesical masses includes cystogram and barium enema to demonstrate displacement of the bladder and sigmoid by an extrinsic mass, as well
as invasive methods, such as seminal vesiculography. The use of sonography has been described and may be especially helpful in confirming the cystic nature of a mass, even if it contains high density hemorrhagic fluid, and localization of large cysts close to the bladder. The sonographic guideline of Littrup et al, which recognizes mullerian duct cysts as discrete hypoechoic or anechoic structures restricted to the posterior base of the prostate and seminal vesicle cysts as discrete anechoic areas greater than 5 mm. in diameter, emphasizes the possibility of accurate diagnosis of cystic retrovesical lesions.I2 Transrectal ultrasound has been increasingly popular as a diagnostic tool to evaluate the prostate and seminal vesicles. When ultrasound was well documented in our patients, intraprostatic or extraprostatic location of a cystic lesion was more readily characterized. Nevertheless, ultrasound is operator dependent and may not accurately depict a dilated tortuous element of the urogenital tract. Myxoid liposarcoma, malignant fibrous histiocytoma, hemangiopericytoma and leiomyosarcoma are rare yet important differential diagnoses of a retrovesical mass. It is essential to minimize the possibility of missing important clues and achieve accurate diagnosis imaging studies, such as CT
m,
1248
RETROVESICAL MASS IN MEN
FIG.5. Proposed diagnostic guideline for cystic retrovesical masses according to clinical symptoms and medial or lateral location to bladder neck on ultrasound. and/or MRI. ''' CT accurately demonstrates the anatomical relationship of associated internal pelvic organs (surrounding fat and pelvic lymph nodes). Thus, absence of or a mass arising in the seminal vesicles is detectable by CT. Disadvantages are radiation exposure and lack of multiplanar capability. A seminal vesicle cyst containing hemorrhagic fluid with spermatozoa may be misinterpreted as malignant tumor.14 In our series CT and MRI disclosed a solid pelvic mass in all cases but the malignant fibrous histiocytoma and hemangiopericytoma were indistinguishable from organized hematomas. Kenney and Leeson reported a similar experience in 4 patients.15 In a 54-year-old man with transitional cell carcinoma of the bladder CT demonstrated a large tumor arising from the left seminal vesicle. Inhomogeneity and high density made a urothelial tumor involving the seminal vesicle likely but a hemorrhagic seminal vesicle cyst was found intraoperatively. Similar cases have been reported.16 In contrast, others have stressed the usefulness of endorectal MRI, which may provide further diagnostic information (additional multiplanar assessment) of the retrovesical mass. However, CT and MRI clearly have a major role in detecting tumor location, and involvement of neighboring organs and lymph nodes. Additionally, information gained by imaging the abdomen and pelvis is significant for choosing an optimal surgical approach to the tumor. 17.1S For rare pelvic masses preoperative or intraoperative biopsy and histopathological examination remain the key for diagnosis.
3. Zinner, A,: Ein Fall von intravesikaler Samenblasenzyste. Wien Med. Wochenschr., 64: 605,1914. 4. Tanagho, E. A.: Embryology of the genitourinary system. In: Smiths General Urology, 14th ed. Edited by E. A. Tanagho and J. A. McAninch. Nonvalk, Connecticut: Appleton & Lange, pp. 1730, 1995. 5. Josso, N.:In vitro synthesis of mullenan-inhibiting hormone by seminiferous tubules isolated from the calf fetal testis. Endocrinology, 93 829, 1973. 6. Beeby, D. I.: Seminal vesicle cyst associated with ipsilateral renal agenesis: case report and review of literature. J . Urol., 112 120, 1974. 7. Devine, C. J., Gonzalez-Serva, L., Stecker, J. F., Jr., Devine, P. C. and Horton, C. E.: Utricular configuration in hypospadias and intersex. J . Urol., 123: 407, 1980. 8. Ritchey, M. L., Benson, R. C., Jr., Kramer, S. A. and Ketalais, P. P.: Management of miillerian duct remnants in the male patient. J. Urol., 140 795, 1988. 9. Mc Neal, J. E. and Bostwick, D. G.: Intraductal dysplasia: a premalignant lesion of the prostate. Hum. Path., 17: 64,1986. 10. Tronosco, P., Babaian, R. J., Ro, J., Grignon, D. J., von Eschenbach, A. C. and Ayala, A. G.: Prostatic intraepithelial neoplasia and invasive prostatic adenomacarcinoma in castoprostatectomy specimens. Urology, suppl., 34: 52, 1989. 11. Kevi, J., Mosotofi, F. K., Heshmat, M. Y . and Enterline, J . P.: Large acinar atypical hyperplasia and carcinoma of the prostate. Cancer, 61: 555, 1988. 12. Littrup, P. J., Lee, F., McLeary, R. D., Wu, D., Lee, A. and Kumasaka, G. H.: Transrectal US of the seminal vesicles and ejaculatory ducts: clinical correlation. Radiology, 168 625, 1988. CONCLUSIONS 13. Genevois, P.A., Van Sinoy, M. L., Sintzoff, S. A., Jr., Stallenberg, Most men with a retrovesical mass present with variable B., Salmon, I., Van Regemorter, G. and Struyven, J.: Cysts of clinical symptoms. A combination of clinical signs (infection), the prostate and seminal vesicle: MR imaging findings in 11 and findings on digital rectal examination and ultrasound cases. AJR, 155 1021, 1990. allow reliable diagnosis of cystic retrovesical lesions in most 14. Kneeland, J . B., Auh, Y. H., McCarron, J. P., Zirinsky, K., cases. The origin of a cystic lesion can be determined dependRubenstein, W. A. and Kazam, E.: Computed tomography, ing on whether location is medial or lateral to the bladder sonography, vesiculography, and MR imaging of a seminal neck. The possible association with congenital disorders of vesicle cyst. J . Comput. Assist. Tomogr., 9 964,1985. the upper urogenital tract warrants further diagnostic pro- 15. Kenney, P.J. and Leeson, M. D.: Congenital anomalies of the seminal vesicles: spectrum of computed tomographic findings. cedures. CT and MRI depict the location of a retrovesical Radiology, 149 247,1983. mass, and involvement of neighboring organs and lymph nodes. However, rare pelvic lesions require an individual 16. Okada, Y.,Tanaka, H., Takeuchi, H. and Yoshida, 0.: Papillary adenocarcinoma in a seminal vesicle cyst associated with ipdiagnostic approach, including biopsy and exploratory lapasilateral renal agenesis: a case report. J. Urol., 148: 1543, rotomy for histopathological examination. 1992. 17. Honig, S. C., Lamont, J. and Oates, R. D.: Ultrasonographic REFERENCES renal and seminal vesicle anomalies in patients with bilateral congenital absence of the vas deferens. J . Urol., part 2, 145: 1. Smith, N. R.: Hydrocele of the seminal vesicle. Lancet, 2: 558, 326,abstract 453,1991. 1872. 2. Englisch, R.: Uber Cysten an der hinteren Blasenwand bei Man- 18. Parsons, R. B., Fisher, A. M., Bar-Chama, N. and Mitty, H. A,: nern. Med. Jahrb. Wien., 1875. MR imaging in male infertility. Radiographics, 17: 627,1997.
Val. 161, 1244-1248. April 1999 Printed in U.S.A.
THEJOLXVALOF UROLOGY Copyright 0 1999 by A~~ERIcAN UROL~CICAL k.J.ocuTlon. IRC
RETROVESICAL MASS IN MEN: PITFALLS OF DIFFERENTIAL DIAGNOSIS STEFAN E. DAHMS, MARKUS HOHENFELLNER, m R G E N F. LINN, CHRISTIAN EGGERSMA", GERALD HAUPT AND JOACHIM W. THUROFF From the Department of Urolog.v, Johannes Gutenberg University, School of M e d i c i ~ Mainz, , Department of Urology and Pediatric Urology, Uniuerstty of Witten JHerdecke, School of Medicine, Klinikum Barmen, Wuppertal and Department of Urology, Ruhr University. School of Medicine, Heme, Germany
ABSTRACT
Purpose: We review the differential diagnosis and treatment of retrovesical masses in men. Materials and Methods: During the last 8 years 21 male patients 3 to 79 years old (mean age 47.1) presented with symptoms or signs of a retrovesical mass. Clinical features and diagnostic findings were reviewed, and related to surgical and histopathological findings. Results: The retrovesical masses included prostatic utricle cyst in 3 cases, prostatic abscess in 1, seminal vesicle hydrops in 6, seminal vesicle cyst in 2, seminal vesicle empyema in 3, large ectopic ureterocele in 1, myxoid liposarcoma in 1, malignant fibrous histiocytoma in 1, fibrous fossa obturatoria cyst in 1, hemangiopericytoma in 1 and leiomyosarcoma in 1. In 17 patients various symptoms were seen and in 4 the mass was incidentally detected. A mass was palpable on digital rectal examination in 16 cases and visible on sonography in 20. For a cystic mass medial location relative to the bladder neck was suggestive of prostatic abscess or utricle cyst, while lateral location was suggestive of seminal vesicle cysthydrops or empyema, ectopic ureter or ureterocele. In 6 patients diagnosis was established only by exploratory laparotomy and histopathological examination. Conclusions: Digital rectal examination and sonography reliably detect a retrovesical mass. Nevertheless, clinical signs and median or lateral location relative to the bladder neck on ultrasound are diagnostic only for cystic lesions. Computerized tomography and magnetic resonance imaging are useful for staging malignant tumors. However, needle or open biopsy is required in most cases to establish a histopathological diagnosis. Exploratory laparotomy and histopathological examination are the procedures of choice when other findings are equivocal. KEYWORDS:diagnosis, treatment outcome, prostate, seminal vesicle
A retrovesical mass that is not related to benign prostatic hyperplasia (BPH) or prostate cancer is uncommon in man. Since 1872 retrovesical cystic structures have stimulated interest in embryology and anatomy of these pathological entities-3 Although modern imaging techniques have increased the diagnostic yield, cystic and solid retrovesical masses still present a diagnostic dilemma. The rarity of these lesions limits clinical experience, and symptoms may mimic other more common diseases of the lower urinary tract. Retrovesical masses may, if at all, influence function of the pelvic organs in various ways and many possible etiologies must be considered. We retrospectively identified characteristic diagnostic features for differential diagnosis of a retrovesical mass.
were available. CT and MRI were evaluated by radiologists who also knew the results of the history, digital rectal examination and ultrasound. CT was performed without and if possible (no history of allergy to contrast medium, normal serum creatinine) with contrast medium, while transabdominal MRI T1 and T2 sequences were obtained with and without gadolinium pentetic acid. Open and endoscopic surgery was performed in 14 and 4 cases, respectively. Of the 3 untreated patients 2 had an asymptomatic seminal vesicle cysthydrops and 1 had a malignant fibrous histiocytoma but died of acute myocardial infarction before surgery. Histopathological examination of the retrovesical masses was performed in all patients and related to the preoperative findings.
PATIENTS AND METHODS
RESULTS
From 1989 to 1997, 21 male patients 3 to 79 years old (mean age 47.1) with retrovesical mass were seen at our institutions. Medical records were reviewed with special attention to clinical presentation, diagnostic tests, operative findings and histopathological diagnosis. History, physical examination, urinalysis, blood cell counts and serum chemistry studies were obtained in all patients. Imaging studies included transvesical ultrasound in 21 cases, excretory urography in 17, urethrocystoscopy in 14, computerized tomography (CT) in 14 and magnetic resonance imaging (MRI) in 14. History, digital rectal examination and ultrasound were performed by urologists and, therefore, all data Accepted for publication November 20, 1998.
Clinical profile. Clinical findings are summarized in the table. Of the 21 patients 17 presented with acute ( 8 ) or chronic (9) symptoms, and in 4 the mass was asymptomatic and found incidentally. Acute symptoms were inflammatory, such as fever with or without flank pain, in 5 patients and noninflammatory, such as urinary retention in 3. In contrast, 9 patients had chronic symptoms, such as perineal pain, frequency, recurrent epididymitis and urinary incontinence. Retrovesical masses were classified by origin as prostatic in 5 cases, seminal vesicle in 11, ureteral in 1 and connective tissue in 4. Digital Rectal Examination: Intraprostatic lesions were noted in 4 of 5 patients with a prostatic mass and asymmetric
1244
RETROVESICAL MASS IN MEN
1245
Classification of retrovesical masses Case - Pt. No. Age
Symptoms
Digital Examination
Diagnostic Procedure
1 - 39
Chronic perineal pain
Intraprostatic lesion
2 - 47
Acute urinary retention
Extraprostatic asymmetric mass
3-69
Painful micturition, fever, perineal pain Chronic painful micturition Chronic perineal pain
Intraprostatic lesion
Extraprostatic asymmetric mass Extraprostatic asymmetric mass Extraprostatic asymmetric mass
Ultrasound,' IVP,urethrocystoscopy* Ultrasound, Tvp, CT,* MRI,* exploratory laparotomy* Ultrasound,* IVP,CT,* urethrocystoscopy* Ultrasound,' IVP,MRI,* urethrocystoscopy Ultrasound,* IVP,MRI," urethrocystoscopy* Ultrasound,* IVP,CT*
4-55 5-
19
Intraprostatic lesion Intraprostatic lesion
7 - 60
Painful micturition, fever, flank pain Fever, urosepsis
8 - 62
None
9 - 69
Acute urinary retention
Extraprostatic asymmetric mass
10 - 50
Fever, flank pain
11 - 50
Chronic frequency
Extraprostatic asymmetric mass Extraprostatic asymmetric mass
12 - 25
Recurrent epididymitis
Unremarkable
13-
6-38
3
Acute urinary retention
Not performed
14 - 35
Recurrent epididymitis
Extraprostatic asymmetric mass
15 - 28
Recurrent epididymitis
16 - 44
None
Extraprostatic asymmetric mass Extraprostatic asymmetric mass
17 - 30
Recurrent epididymitis
Extraprostatic asymmetric mass
18 - 79
Urinary incontinence
Extraprostatic asymmetric mass
19 - 57
None
Unremarkable
20 - 67
Acute urinary retention
Retrorectal mass
21-63
None
Retrovesical mass
:
Ultrasound,* IVP,CT,* urethrocystoscopy Ultrasound,* IVP,MRI,* urethrocystoscopy, needle aspiration biopsy* Ultrasound, NP, uretbrocystoscopy, exploratory laparotomy* Ultrasound,* IW, radioisotope scan, CT, MRIf Ultrasound,* radioisotope scan, CT,* MRI,* urethrocystoscopy Ultrasound,* MRI,* urethrocystoscopy Ultrasound,* MRI*
Location
Diagnosis
Surgical Treatment
Prostate
Utricle cyst
Unroofing
Prostate
Myxoid liposarcoma
Prostate
Abscess
Prostate
Utricle cyst
Extirpation, cystoprostatectnmy, Mainz pouch I Unroofing and drain age Unroofing
Prostate
Utricle cyst
Unroofing
Seminal vesicle
Empyema
Extirpation
Seminal vesicle
Empyema
Extirpation
Seminal vesicle
cyst
None
Seminal vesicle
cyst
Extirpation
Seminal vesicle
Empyema
Extirpation
Seminal vesicle
Hydrops
Nephmureterectomy. vesicle extirpation
Seminal vesicle
Hydmps
Seminal vesicle
Hydrops
Nephroureterectomy, vesicle extirpation Nephmuretereetomy, vesicle extirpation Nephroureterectomy, vesicle extirpation
Ultrasound,* IW, Seminal vesicle radioisotope scan, CT,* urethrocystoscopy* Ultrasound,* IVP,radioSeminal vesicle isotope scan, CT,* MRI* Ultrasound,* IVF', radioSeminal vesicle isotope scan, CT,* MRI,* needle aspiration biopsy* Ultrasound, IVP,radioiso- Ureter tope scan, CT, MRI, urethrocystoscopy, explora t o j laparotimy* Ultrasound, M', CT, Connective tissue MRI, urethrocystoscopy, needle biopsy' Ultrasound, IVP,CT, Connective tissue MRI, urethrocystoscopy, exploratory laparotomy* Ultrasound, CT, MRI, exConnective tissue ploratory laprotomy* Ultrasound, NP,CT, ureConnective tissue throcystoscopy, needle biopsy, exploratory laparotornv*
Hydrops Hydrops Hydrops
Nephroureterectomy, vesicle extirpation None
.
Ectopic uretero cele
Nephroureterectomy ureterocele extirpation
Malignant fibrous histiocytoma
None (died of acute myocardial infarction) Extirpation
Fibrous fossa obturatoria cyst Hemangiopericytoma Leiomyosarcoma
Extirpation Extirpation
* Guiding diagnostic procedure.
extraprostatic masses were detected in 8 of 11with a seminal vesicle mass. The patient with a ureteral mass had a large mobile extraprostatic tumor. In addition, digital rectal examination revealed connective tissue masses in 1patient with a large asymmetric extraprostatic mass, 1 with a retrorectal tumor and 1 with a retrovesical mass 2 years after radical prostatectomy for margin positive prostate cancer. Urinalysis: Urinalysis demonstrated leukocyturia and m i c n hematuria in all cases of prostatic and seminal vesicle masses except those with asymptomatic seminal vesicle c y s t h y ~ p s . Urine leukocytes and white blood count were significantly higher for a prostatic abscess or seminal vesicle empyema than for a simple prostatic utricle and seminal vesicle cyst. Urindysis and blood count were normal in the case of ureteral mass. Microhematuria was present in the 3 patients with retrovesical connective tissue masses when digital rectal examination was suggestive of tumor. Ln the other patient with an unremarkable digital rectal examination (case 19) laboratory studies revealed no pathological findings.
Imaging studies. Ultrasound revealed cystic lesions in 16 patients and solid masses in 5. Medial locations of a cystic retrovesical mass were consistent with a prostatic utricle cyst (single small lesion in the dorsomedial aspect of the prostate, fig. 1) or abscess (multiple cavities without evidence of a preferred area, fig. 2). Additional transrectal ultrasound in 2 patients confirmed intraprostatic location of a cystic structure. Ultrasound in the patient with the myxoid liposarcoma (case 2) revealed a mass 7.5 cm. in diameter but was inconclusive regarding its relationship to neighboring structures. A cystic extraprostatic mass lateral to the bladder neck was demonstrated on ultrasound for all seminal vesicle or ureteral masses, unlike prostatic masses in medial locations, which were not visible. In 1 patient a seminal vesicle cyst was misinterpreted as BPH associated with a bladder stone. However, ultrasound correctly identified solid retrovesical connective tissue masses in all 5 cases. A nonfunctioning or absent kidney was revealed on IVP in 13 patients with seminal vesicle (ll),ureteral (1) and pros-
1246
RETROVESICAL MASS IN MEN
FIG. 1. Transrectal ultrasound (axial scan, 7.5 MHz. transducer) shows intraprostatic midline cyst in case 1.
tatic (1) masses. In the patient with a retrovesical connective tissue mass, and inconclusive digital rectal examination and laboratory tests (case 19) IVP demonstrated slight elevation of the bladder on the left side. CT and/or MRI accurately depicted prostatic utricle cysts, intraprostatic abscess cavities and a pelvic mass (case 2 , fig. 3), as well as seminal vesicle cystdhydropses and empyemas. However, CT diagnosed the ureteral mass as a pelvic cyst. Both imaging studies failed to detect a hypoplastic kidney found intraoperatively but revealed solid retrovesical connective tissue masses in all 4 cases. However, in 2 patients (cases 18 and 20) CT misinterpreted the tumors as organized hematomas, 1 of which was misinterpreted on MRI (fig. 4). In the patient with previous radical prostatectomy for adenocarcinoma of the prostate (case 21) CT demonstrated a 10 X 8 X 10 cm. mass encompassing the bladder and rectum. Histopathological examination of needle biopsies demonstrated connective tissue and leiomyoma but no sign of malignancy. In all cases assessment relative to mass location, involvement of neighboring organs and lymph nodes was accurate. On urethrocystoscopy prostatic utricle cysts were seen as obstruction of the bladder outlet and prostatic abscess presented as a diffuse enlargement of the prostate. Compression of the posterior bladder wall and absence of the ureteral orifice were seen in patients with seminal vesicle retrovesical masses. The patient with a misleading ultrasound had extensive bladder trabeculation and an intravesical calculus suggesting bladder outlet obstruction. On urethrocystoscopy the bladder neck appeared obstructed and a ureteral orifice was absent on the ipsilateral side. Surgical management. The mass as demonstrated on preoperative imagmg studies was confirmed in all patients who underwent surgery. Prostatic utricle and seminal vesicle cysts were treated only if symptomatic. Transurethral unroofing of prostatic utricle cysts (3 cases) and drainage of the prostatic abscess were uncomplicated. Seminal vesicle cysts/ hydropses were excised when symptomatic (6 cases) as were empyemas (3)without significant morbidity. Diagnosis of the 2 asymptomatic seminal vesicle cystshydropses was established by needle aspiration biopsy, which revealed seminal fluid containing numerous spermatozoa. In 6 cases exploratory laparotomy and histopathological examination were necessary to establish diagnosis of the pelvic mass. Prostatectomy was planned in the patient in whom ultrasound had revealed no mass but was suggestive of BPH associated with a bladder stone (case 9). ARer intraoperative incision of the bladder neck approximately 300 to 400 ml. hemorrhagic fluid leaked, and subsequently a bladder stone and large seminal vesicle cyst were removed. Convalescence was uneventful.
The patient with a hypoplastic kidney found only at laparotomy (case 17) had a large ectopic ureterocele at the bladder neck. Preoperative transabdominal ultrasound demonstrated no kidney in the normal location or hypoplastic kidney in the pelvis. Transrectal ultrasound revealed a cystic structure close to the left side of the bladder neck with questionable involvement of the left seminal vesicle but no hypoplastic kidney. IVF' showed no left kidney and displacement of the bladder to the right side. Radioisotope scan was unable to demonstrate a functioning left kidney. CT and MRI depicted a cystic mass ("an approximately 3 cm. in diameter diverticulum-like structure where normally the ureter leads into the bladder") which showed enhancement with contrast medium. Seminal vesicles could be distinguished from the cystic mass without involvement. Intraoperatively a tiny hypoplastic kidney was found close to the cyst, which appeared to be a large ureterocele. Seminal vesicles and ducts showed no pathological findings, and excision of the hypoplastic kidney, ureter and ureterocele was performed. In patients with seminal vesicle hydrops (cases 11 to 15) a hypoplastic kidney and ectopic ureter originating from the seminal vesicle were found intraoperatively, and nephroureterectomy and extirpation of the seminal vesicle were performed. Convalescence was uneventful in all cases. The fossa obturatoria cyst (case 19), hemangiopericytoma (case 20) and leiomyosarcoma (case 21) were intraoperatively diagnosed by histopathological examination and excised. The patient with malignant fibrous histiocytoma died of acute myocardial infarction before surgery and histopathological evaluation was obtained by needle biopsy. The patient with the leiomyosarcoma underwent open surgery (case 21), and the 500 gm. tumor was where the prostate had been and was extirpated. The patient with intraoperatively confirmed myxoid liposarcoma of the prostate (case 2) was treated with radical cystoprostatectomy and Mainz pouch I urinary diversion without complications, and 2-year followup examination revealed no recurrence. DISCUSSION
Retrovesical masses can be classified as congenital or acquired,4,5 or according to organ specific pathology. During embryological development of the genitourinary tract the mesonephric duct (wolffian duct) and the ureteral bud join the urogenital sinus. The opening of the wolffian duct migrates medial downward, whereas the ureteral bud develops upward and lateral. The final position of these structures determines the ingrowth of mesodermal tissue, which later differentiates into the trigonal structures of the bladder. Just above and below the mesonephric duct the prostate gland develops from branching epithelial outgrowths. In male subjects the wolffian duct differentiates into the genital duct system, forming the epididymis, vas deferens, seminal vesicles and ejaculatory ducts.4 Mullerian regression factor causes regression of the mullerian duct.5 If the gonad begins t o differentiate into an ovary, the wolffian duct remains rudimentary. The mullerian duct contributes to the uterine tubes, uterus and most of the vagina. Possible reasons for various malformations, such as prostatic utricle cyst, seminal vesicle cysthydrops, ureterocele and ectopic ureter, are the close spatial relationship among the mullerian duct, wolffian duct and ureter, and defective regression of the mullerian duct. The association with other congenital disorders, such as ipsilateral agenesis of the kidney, ureter and hemitrigone, hypospadias and intersex is well recognized, and emphasizes the need for further examination of the upper urogenital tract.6-8 Retrovesical masses have no classic clinical presentation and most symptoms are nonspecific, even if the tumor is large. Duration of symptoms (acute or chronic) and location of retrovesical cystic lesions medial or lateral to the bladder
RETROVESICAL MASS IN MEN
1247
F I ~2.. Transrectal ultrasound (axial scan, 7.5 MHz. transducer) (A) and transverse CT ( B ) demonstrate multiple intraprostatic cystic cavities in case 3.
F ~ 3 .~sagittal , MRI of pelvis ( ~ 1 - ~ ~ i ~reveals h t ~ dlarge ) retrovesical mass with homogeneous signal intensity in case 2.
FIG. 4. Sa 'ttal MRI of pelvis demonstrates 10 X 17 cm. retrovesical mass Witf COmpreSSiOn but without involvement of bladder in case 20.
neck guide diagnosis (fig. 5). In contrast, since only a relatively small number of patients with solid retrovesical masses were included in our study and histopathological findings were rare, an algorithm for diagnosis of solid masses could not be developed. Chronic symptoms, such as impaired voiding, perineal pain and recurrent epididymitis, are poor diagnostic guides. Acute symptoms of sepsis with and without urinary retention or other voiding symptoms are suggestive of prostatic abscess, and prostatic utricle and seminal vesicle empyema. Various studies have demonstrated that comparison of needle biopsies with findings of surgical or autopsy specimens may present a diagnostic dilemma since detection of a mass with benign pathology does not necessarily mean that carcinoma is not also present. For example, 4 to 8%of benign prostates contain areas of grade 3 prostatic intraepithelial neoplasia and up to 68% may have foci of grade 2 prostatic intraepithelial neoplasia.9-11 Since needle biopsies are operator dependent, there is concern in uncertain cases that carcinoma is present but not detected due to sampling errors. Radiographic evaluation of retrovesical masses includes cystogram and barium enema to demonstrate displacement of the bladder and sigmoid by an extrinsic mass, as well
as invasive methods, such as seminal vesiculography. The use of sonography has been described and may be especially helpful in confirming the cystic nature of a mass, even if it contains high density hemorrhagic fluid, and localization of large cysts close to the bladder. The sonographic guideline of Littrup et al, which recognizes mullerian duct cysts as discrete hypoechoic or anechoic structures restricted to the posterior base of the prostate and seminal vesicle cysts as discrete anechoic areas greater than 5 mm. in diameter, emphasizes the possibility of accurate diagnosis of cystic retrovesical lesions.I2 Transrectal ultrasound has been increasingly popular as a diagnostic tool to evaluate the prostate and seminal vesicles. When ultrasound was well documented in our patients, intraprostatic or extraprostatic location of a cystic lesion was more readily characterized. Nevertheless, ultrasound is operator dependent and may not accurately depict a dilated tortuous element of the urogenital tract. Myxoid liposarcoma, malignant fibrous histiocytoma, hemangiopericytoma and leiomyosarcoma are rare yet important differential diagnoses of a retrovesical mass. It is essential to minimize the possibility of missing important clues and achieve accurate diagnosis imaging studies, such as CT
m,
1248
RETROVESICAL MASS IN MEN
FIG.5. Proposed diagnostic guideline for cystic retrovesical masses according to clinical symptoms and medial or lateral location to bladder neck on ultrasound. and/or MRI. ''' CT accurately demonstrates the anatomical relationship of associated internal pelvic organs (surrounding fat and pelvic lymph nodes). Thus, absence of or a mass arising in the seminal vesicles is detectable by CT. Disadvantages are radiation exposure and lack of multiplanar capability. A seminal vesicle cyst containing hemorrhagic fluid with spermatozoa may be misinterpreted as malignant tumor.14 In our series CT and MRI disclosed a solid pelvic mass in all cases but the malignant fibrous histiocytoma and hemangiopericytoma were indistinguishable from organized hematomas. Kenney and Leeson reported a similar experience in 4 patients.15 In a 54-year-old man with transitional cell carcinoma of the bladder CT demonstrated a large tumor arising from the left seminal vesicle. Inhomogeneity and high density made a urothelial tumor involving the seminal vesicle likely but a hemorrhagic seminal vesicle cyst was found intraoperatively. Similar cases have been reported.16 In contrast, others have stressed the usefulness of endorectal MRI, which may provide further diagnostic information (additional multiplanar assessment) of the retrovesical mass. However, CT and MRI clearly have a major role in detecting tumor location, and involvement of neighboring organs and lymph nodes. Additionally, information gained by imaging the abdomen and pelvis is significant for choosing an optimal surgical approach to the tumor. 17.1S For rare pelvic masses preoperative or intraoperative biopsy and histopathological examination remain the key for diagnosis.
3. Zinner, A,: Ein Fall von intravesikaler Samenblasenzyste. Wien Med. Wochenschr., 64: 605,1914. 4. Tanagho, E. A.: Embryology of the genitourinary system. In: Smiths General Urology, 14th ed. Edited by E. A. Tanagho and J. A. McAninch. Nonvalk, Connecticut: Appleton & Lange, pp. 1730, 1995. 5. Josso, N.:In vitro synthesis of mullenan-inhibiting hormone by seminiferous tubules isolated from the calf fetal testis. Endocrinology, 93 829, 1973. 6. Beeby, D. I.: Seminal vesicle cyst associated with ipsilateral renal agenesis: case report and review of literature. J . Urol., 112 120, 1974. 7. Devine, C. J., Gonzalez-Serva, L., Stecker, J. F., Jr., Devine, P. C. and Horton, C. E.: Utricular configuration in hypospadias and intersex. J . Urol., 123: 407, 1980. 8. Ritchey, M. L., Benson, R. C., Jr., Kramer, S. A. and Ketalais, P. P.: Management of miillerian duct remnants in the male patient. J. Urol., 140 795, 1988. 9. Mc Neal, J. E. and Bostwick, D. G.: Intraductal dysplasia: a premalignant lesion of the prostate. Hum. Path., 17: 64,1986. 10. Tronosco, P., Babaian, R. J., Ro, J., Grignon, D. J., von Eschenbach, A. C. and Ayala, A. G.: Prostatic intraepithelial neoplasia and invasive prostatic adenomacarcinoma in castoprostatectomy specimens. Urology, suppl., 34: 52, 1989. 11. Kevi, J., Mosotofi, F. K., Heshmat, M. Y . and Enterline, J . P.: Large acinar atypical hyperplasia and carcinoma of the prostate. Cancer, 61: 555, 1988. 12. Littrup, P. J., Lee, F., McLeary, R. D., Wu, D., Lee, A. and Kumasaka, G. H.: Transrectal US of the seminal vesicles and ejaculatory ducts: clinical correlation. Radiology, 168 625, 1988. CONCLUSIONS 13. Genevois, P.A., Van Sinoy, M. L., Sintzoff, S. A., Jr., Stallenberg, Most men with a retrovesical mass present with variable B., Salmon, I., Van Regemorter, G. and Struyven, J.: Cysts of clinical symptoms. A combination of clinical signs (infection), the prostate and seminal vesicle: MR imaging findings in 11 and findings on digital rectal examination and ultrasound cases. AJR, 155 1021, 1990. allow reliable diagnosis of cystic retrovesical lesions in most 14. Kneeland, J . B., Auh, Y. H., McCarron, J. P., Zirinsky, K., cases. The origin of a cystic lesion can be determined dependRubenstein, W. A. and Kazam, E.: Computed tomography, ing on whether location is medial or lateral to the bladder sonography, vesiculography, and MR imaging of a seminal neck. The possible association with congenital disorders of vesicle cyst. J . Comput. Assist. Tomogr., 9 964,1985. the upper urogenital tract warrants further diagnostic pro- 15. Kenney, P.J. and Leeson, M. D.: Congenital anomalies of the seminal vesicles: spectrum of computed tomographic findings. cedures. CT and MRI depict the location of a retrovesical Radiology, 149 247,1983. mass, and involvement of neighboring organs and lymph nodes. However, rare pelvic lesions require an individual 16. Okada, Y.,Tanaka, H., Takeuchi, H. and Yoshida, 0.: Papillary adenocarcinoma in a seminal vesicle cyst associated with ipdiagnostic approach, including biopsy and exploratory lapasilateral renal agenesis: a case report. J. Urol., 148: 1543, rotomy for histopathological examination. 1992. 17. Honig, S. C., Lamont, J. and Oates, R. D.: Ultrasonographic REFERENCES renal and seminal vesicle anomalies in patients with bilateral congenital absence of the vas deferens. J . Urol., part 2, 145: 1. Smith, N. R.: Hydrocele of the seminal vesicle. Lancet, 2: 558, 326,abstract 453,1991. 1872. 2. Englisch, R.: Uber Cysten an der hinteren Blasenwand bei Man- 18. Parsons, R. B., Fisher, A. M., Bar-Chama, N. and Mitty, H. A,: nern. Med. Jahrb. Wien., 1875. MR imaging in male infertility. Radiographics, 17: 627,1997.