Prostate gland & seminal vesicles
General
Anatomy & histology-seminal vesicles / ejaculatory duct
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PubMed Search: Seminal vesicles / ejaculatory duct
Table of Contents
Definition / general | Essential features | Terminology | ICD coding | Epidemiology | Sites | Pathophysiology | Etiology | Diagrams / tables | Clinical features | Diagnosis | Laboratory | Radiology description | Radiology images | Case reports | Treatment | Clinical images | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Sample pathology report | Differential diagnosis | Additional references | Board review style question #1 | Board review style answer #1 | Board review style question #2 | Board review style answer #2Cite this page: Shoaib F, Okafor C, Yeh YA. Anatomy & histology-seminal vesicles / ejaculatory duct. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/prostateseminalves.html. Accessed December 16th, 2024.
Definition / general
- Seminal vesicles: a pair of highly coiled tubular glands positioned below the posterior wall of the urinary bladder; produces fluid and nutrient constituents of semen (Pawlina: Histology - A Text and Atlas, 8th Edition, 2018)
- Nonneoplastic diseases of the seminal vesicles, including but not limited to congenital anomalies of seminal vesicles, seminal vesiculitis and seminal vesicle calculi
Essential features
- Seminal vesicles are paired, highly coiled, tubular structures composed of ducts and glands lined by pseudostratified cuboidal to columnar epithelial cells and basal cells
- Golden brown lipofuscin pigments are noted in many cells; there are a few monstrous cells and atypical cells with nuclear invaginations (Mills: Histology for Pathologists, 3rd Edition, 2006)
- Epithelial cells stain positive for MUC6, PAX2, PAX8, GATA3, CK7, AE1 / AE3, CAM 5.2, CK5/6, CK19, p63 and CD10
- CK20, cytokeratin 34 beta E12 and NKX3.1 immunomarkers are negative (Am J Surg Pathol 2003;27:519, Hum Pathol 2010;41:1145, Ann Diagn Pathol 2020;49:151644)
- Nonneoplastic diseases of the seminal vesicles include congenital anomalies (agenesis, hypoplasia, malformations), seminal vesicle cysts, seminal vesiculitis, calcification and calculi
Terminology
- Vesicular glands (seminal glands)
- Agenesis of seminal vesicle
- Congenital anomalies of the seminal vesicles
- Seminal vesicle cysts
- Seminal vesiculitis
- Seminal vesicle calculi
ICD coding
Epidemiology
- Congenital anomalies
- Agenesis: rare; reported incidence of 0.08% in a series of robotic assisted radical prostatectomy (Can J Urol 2009;16:4601)
- Zinner syndrome (congenital seminal vesicle cyst and ipsilateral renal agenesis): reported incidence of 0.00035 - 0.0046% (Radiol Case Rep 2020;15:437)
- Congenital cysts: 18 - 41 years of age (J Urol 1978;119:555)
- Commonly found in 60% of autosomal dominant polycystic kidney disease (Nephrol Dial Transplant 1998;13:2825)
- Seminal megavesicle (ectasia): 23% of men with adult polycystic kidney disease (Clin Imaging 2015;39:289)
- Benign seminal vesicle cyst
- Incidence: rare, 0.001% (Scand J Urol Nephrol 1979;13:113)
Sites
- Seminal vesicles are a pair of convoluted tubular glands located in the space between the urinary bladder and the rectum
- Glands are positioned superior to the rectum, inferior to the fundus (posteroinferior part) of the bladder and posterior to the prostate
- They are separated from the rectum by Denonvilliers fascia
- Reference: J Anat 1985;143:45
Pathophysiology
- Congenital anomalies of the seminal vesicles
- During the tenth week of fetal development, the distal mesonephric duct proliferates and forms the epididymis, ductus deferens and a bullous outpouching, of which the seminal vesicles develop under the influence of testosterone (J Anat 1985;143:45)
- Complete or partially complete failure to develop results in agenesis, hypoplasia or cysts (Urology 1997;49:313)
- Acute seminal vesiculitis: retrograde infection with or without indwelling urinary catheter, commonly associated with prostatitis and epididymitis (Br J Urol 1991;67:632)
- Seminal vesicle calcification and calculi: may be caused by reflux of urine (Curr Urol 2019;12:113)
Etiology
- Congenital anomalies of seminal vesicle: a developmental anomaly of the mesonephric duct (Urology 1997;49:313)
- Seminal vesicle cysts: congenital or acquired
- Seminal vesiculitis: inflammation of the seminal vesicles
- Seminal vesicle calculi: inflammatory (after seminal vesiculitis) or noninflammatory (Curr Urol 2019;12:113)
Diagrams / tables
Images hosted on other servers:
Seminal vesicles and prostate
Clinical features
- Congenital anomalies
- Agenesis and hypoplasia (Urology 2021;149:e44)
- Infertility: agenesis often associated with decreased semen volume, hypospermia or azoospermia, abnormal sperm motility and absence of coagulative activity (Can Urol Assoc J 2014;8:E266)
- Bilateral agenesis: mostly seen in patients with cystic fibrosis (J Clin Pathol 1969;22:725)
- Unilateral duplication of seminal vesicle (Urology 1999;54:162)
- Commonly associated with maldevelopment of other mesonephric growth
- Agenesis and hypoplasia (Urology 2021;149:e44)
- Seminal vesicle cysts (Arch Esp Urol 2004;57:165)
- Vague symptoms: perineal pain during ejaculation or defecation, dysuria, urinary retention, recurrent epididymitis
- Congenital cysts
- Zinner syndrome: congenital seminal vesicle cyst, ipsilateral obstruction of the ejaculatory duct, ipsilateral renal agenesis and commonly with ureteral ectopia (Int J Surg Case Rep 2022;97:107434, J Urol 1976;116:833)
- Case with monorchia (J Urol 1980;124:574)
- Cases with hemivertebra (J Urol 1993;150:1214)
- Acquired cysts: associated with inflammation and obstruction of the ejaculatory ducts (Br J Urol 1992;69:636)
- Seminal vesiculitis
- Irritative voiding symptoms, fever, scrotal and testicular pain, perineal and rectal pain and purulent ejaculation may occur (Actas Urol Esp 2005;29:523)
- Acute vesiculitis: caused by retrograde infection
- Chronic vesiculitis: associated with chronic prostatitis
- Schistosomiasis: usually with S. haematobium infection of the bladder
- Viruses (cytomegalovirus), fungi, parasites (Int J Surg Pathol 2016;24:720)
- Echinococcal (hydatid) cyst (Int J Urol 2006;13:308)
- Calcification and calculi
- Hematospermia and painful ejaculation (Scand J Urol 2017;51:237)
- Often associated with postinfection (particularly tuberculosis)
- Dystrophic calcifications: associated with diabetes mellitus or uremia (J Urol 1971;105:542)
Diagnosis
- Symptoms and signs: hematospermia, lumbosacral and perineal pain, groin pain, painful ejaculation, dysuria, hematuria, oligospermia, azoospermia (Int J Reprod Biomed 2016;14:293)
- Digital rectal examination (DRE): detection of enlarged seminal vesicle cysts
- Transrectal ultrasound (TRUS): normal seminal vesicles show elongated mass superior to prostate (Int J Reprod Biomed 2016;14:293)
- Computed tomography: contrast enhanced CT shows fluid filled structure with a thin septa
- Magnetic resonance imaging (MRI): normal seminal vesicles show elongated, fluid filled structure with thin septa (Semin Roentgenol 1993;28:83)
- Transurethral seminal vesiculoscopy
Laboratory
- Seminal fluid analysis (Fertil Steril 2015;103:e18)
- Low semen volume: < 1.5 mL
- Low sperm count: < 10 million/mL
- Sperm vitality: high number of immotile and nonviable sperm
- Sperm morphology: abnormal sperm morphology suggestive of abnormal spermatogenesis
- Other cells: assessed with peroxidase activity and leukocyte markers
Radiology description
- MRI shows normal seminal vesicles with clustered, grape-like appearance (J Clin Imaging Sci 2014;4:61)
- Axial contrast enhanced CT scan and MRI show absence of the seminal vesicle in agenesis of the organ (AJR Am J Roentgenol 2007;189:130)
- Cysts within the seminal vesicle may be seen on a CT scan or MRI
- MRI shows mild asymmetric dilation of the seminal vesicle with focal areas of wall thickening in acute seminal vesiculitis (J Clin Imaging Sci 2014;4:61)
Radiology images
Images hosted on other servers:
Normal seminal vesicles
Agenesis
Cyst
Seminal vesiculitis
Case reports
- 31 year old man presented with hemorrhagic giant seminal vesicle cyst (Medicine (Baltimore) 2021;100:e26142)
- 33 year old man with symptomatic Zinner syndrome (Int J Surg Case Rep 2020;73:61)
- 45 year old man with functional obstruction and painful ejaculation (Asian J Androl 2017;19:256)
- 63 year old man with giant seminal vesicle cyst in Zinner syndrome (Medicine (Baltimore) 2022;101:e31577)
- 66 year old man with seminal vesicle fistula as complication of Crohn's disease (BMJ Case Rep 2022;15:e226445)
Treatment
- Antibiotics therapy for bacterial seminal vesiculitis
- Complete surgical excision of seminal vesiculitis complicated by abscess, fistula or stricture
- Surgical excision of symptomatic seminal vesicle cysts (Int J Surg Case Rep 2020;73:61)
- Transurethral seminal vesiculoscopy and lithotripsy for small calculi
- Transperitoneal laparoscopic procedure for large calculi (Scand J Urol 2017;51:237)
Clinical images
Images hosted on other servers:
Cyst
Stones
Gross description
- Normal seminal vesicle (Mills: Histology for Pathologists, 3rd Edition, 2006)
- 2 highly convoluted, lobulated and tubular structures posterolateral to base of the urinary bladder and parallel with the ampulla of vas deferens
- 3.5 - 7.5 cm in length; 1.2 - 2.4 cm in thickness
- Duplication of main duct, each measuring 10 - 15 cm, may present (10%)
- Main duct has 8 first order branching ducts and several secondary ducts
- Short excretory duct joins the ampulla of the vas deferens to form ejaculatory duct
- Muscular layers, including outer longitudinal and inner circular, are thinner than that of the vas deferens
- Normal ejaculatory duct (Mills: Histology for Pathologists, 3rd Edition, 2006)
- Short paired ducts, each measuring 1.5 cm
- Convergence of the excretory duct and the ampulla of vas deferens
- Extends into the prostatic central zone and enters the posterior distal prostatic urethra at the verumontanum
- Agenesis of seminal vesicles (J Urol 1998;160:2126)
- Absence of seminal vesicles (unilateral or bilateral)
- Seminal vesicle cysts (Urology 2004;63:584)
- Usually unilateral and unilocular, lateral to midline, up to 3 times larger than normal seminal vesicle, smaller than Müllerian duct cyst
- Gigantic cyst may occur
- Seminal vesicle calcification and calculi (Br J Urol 1991;68:322)
- Brown stones, measuring up to 1 cm
- Consists of phosphate and carbonate salts
Gross images
Images hosted on other servers:
Normal seminal vesicle
Acquired cystic dilatation
Cyst
Calculus
Microscopic (histologic) description
- Normal seminal vesicle (Mills: Histology for Pathologists, 3rd Edition, 2006)
- Seminal vesicle wall consists of a thin, external, longitudinal muscle and a thicker, internal, circular muscle
- Complex alveolus-like papillary mucosal folds lined by stratified columnar epithelium; basal cells are present
- Columnar epithelial cells with short microvilli and cytoplasmic golden brown lipofuscin pigment that are also found in ampulla of vas deferens and ejaculatory duct
- 2 types of lipofuscin pigment
- Type 1: uniform size (1 - 2 μm); coarse, highly refractile, golden brown granules
- Type 2: variable size (0.25 - 4 μm); nonrefractile and yellow-brown, gray-brown or blue-pink
- Atypical monstrous epithelial cells characterized by enlarged hyperchromatic and irregular nuclei; may represent response to hormones (i.e., Arias-Stella reaction) and are increased in aged seminal vesicles (Int J Clin Exp Pathol 2011;4:727)
- Lumen contains eosinophilic crystalloid secretions and dense, plate-like secretions mimicking that of prostate adenocarcinoma; spermatozoa may be present (Arch Pathol Lab Med 2001;125:141)
- Eosinophilic hyaline bodies (small, 15 - 20 μm) represent degenerating smooth muscle cells that are present in the muscular wall of seminal vesicles, vas deferens and in fibromuscular tissue of prostate
- Normal ejaculatory duct (Mills: Histology for Pathologists, 3rd Edition, 2006)
- Cells lining the epithelium resemble the seminal vesicle and ampulla of the vas deferens
- Ductal cells may contain lipofuscin pigment and are negative for prostate specific antigen (PSA)
- Seminal vesicle cysts (Yonsei Med J 2009;50:560)
- Unilocular cyst is lined by cuboidal or flattened epithelium and consists of fibrous wall
- Seminal vesicle calcification and calculi: calcified material and calculi in the lumens
Microscopic (histologic) images
Contributed by Faryal Shoaib, M.D., Y. Albert Yeh, M.D., Ph.D. and Andres Matoso, M.D.
Multilobulated tubular structures
Branching side ducts
Lining columnar cells
Enlarged epithelial cells
Large atypical cells
Alveolar-like mucosal folds
Eosinophilic crystalloids
Stromal hyaline body
Stromal hyaline body
Stromal hyaline body
Monstrous epithelial cells
Prostatic glands
Nuclear pleomorphism
Yellow pigment
Positive stains
- Seminal vesicle tissue
- MUC6 in contrast to prostate (negative) (Am J Surg Pathol 2003;27:519)
- PAX2 in contrast to prostate (negative) (Hum Pathol 2010;41:1145)
- GATA3 (Actas Urol Esp 2017;41:577)
- CK7 (Hum Pathol 2017;69:123)
- PAX8 (Hum Pathol 2017;69:123)
- Pancytokeratin AE1 / AE3
- CAM 5.2
- CK5/6 (Int J Clin Exp Pathol 2011;4:727)
- CK19 (Int J Clin Exp Pathol 2011;4:727)
- p63
- CD10 (Int J Clin Exp Pathol 2011;4:727)
- PSA and PSAP could be positive (Histopathology 2004;44:405)
Negative stains
- Seminal vesicle tissue
Sample pathology report
- Prostate, right base, needle biopsy:
- Benign prostatic tissue and seminal vesicle, negative for carcinoma (see comment)
- Comment: The prostate biopsy shows prostatic glands and fibromuscular stroma. There is a group of small glands lined by epithelial cells with bland nuclei. A few atypical cells with slightly enlarged nuclei are noted. Immunohistochemical stains MUC6, PAX2, PAX8, CK7 and CK5/6 are positive in this group of small glands. NKX3.1 and PSA are negative. These features are consistent with seminal vesicle tissue. There is no evidence of carcinoma.
Differential diagnosis
- Normal seminal vesicle:
- Prostatic adenocarcinoma (Am J Surg Pathol 2003;27:519):
- High grade prostatic intraepithelial neoplasia (Mod Pathol 2004;17:360):
- Diffuse enlargement of nuclei with atypia, hyperchromasia and prominent nucleoli
- Lacks type 1 golden brown refractile lipofuscin pigment
- Seminal vesicle cyst:
- Large, lateral, may contain spermatozoa (Urology 2004;63:584)
- Diverticulum of ejaculatory duct:
- Variable in size, usually midline, may contain spermatozoa
- Prostatic cyst:
- Variable in size, usually lateral, lack of spermatozoa
- Müllerian duct cyst:
- Large, usually midline, lacks spermatozoa
- Diverticulum of ejaculatory duct:
- Large, lateral, may contain spermatozoa (Urology 2004;63:584)
- Ectopic prostatic tissue (Urology 1996;48:490):
Additional references
Board review style question #1
A 74 year old man was found to have an elevated PSA of 8.0 in a routine health examination. A prostate needle biopsy was performed and revealed a prostatic adenocarcinoma, Gleason score 4 + 3, with perineural invasion. Radical prostatectomy was performed. A photomicrograph of one of the tissue sections is shown above. What is the diagnosis?
- Adenocarcinoma of the seminal vesicle
- Cystadenoma of the seminal vesicle
- High grade prostatic intraepithelial neoplasia
- Normal seminal vesicle
- Prostatic acinar adenocarcinoma, Gleason score 4 + 3
Board review style answer #1
D. Normal seminal vesicle. The image shows glands lined by pseudostratified, cuboidal secretory cells and basal cells. The ductal and glandular lumens contain many eosinophilic crystalloids with some eosinophilic, plate-like crystalloids. These features are characteristic of normal seminal vesicles. Answer B is incorrect because the alveolar-like mucosal folds are lined by normal cuboidal to columnar epithelial cells. Answers C and E are incorrect because this is not prostatic tissue, although there are some crystalloids in the ductal and glandular lumens. Answer A is incorrect because there are no malignant glands in the seminal vesicle.
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Reference: Seminal vesicles / ejaculatory duct
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Reference: Seminal vesicles / ejaculatory duct
Board review style question #2
A 64 year old man was found to have an elevated PSA of 10.2 in a routine health examination. A prostate needle biopsy was performed and revealed a prostatic adenocarcinoma, Gleason score 4 + 4, with perineural invasion. Radical prostatectomy was performed. A photomicrograph of one of the tissue sections is shown above. The epithelial cells are positive for MUC6 and PAX2 immunohistochemical stains. What is the diagnosis?
- Adenocarcinoma of the seminal vesicle
- High grade prostatic intraepithelial neoplasia
- Normal seminal vesicle
- Prostatic acinar adenocarcinoma, Gleason score 4 + 4, tertiary 5
- Seminal vesicle with dysplasia
Board review style answer #2
C. Normal seminal vesicle. Seminal vesicles stain positive for MUC6 and PAX2 immunomarkers, while prostatic glands are negative for the 2 biomarkers. Answers B and D are incorrect because this is not prostatic tissue. Answers A and E are incorrect because there are no malignant or dysplastic cells in the seminal vesicle. The atypical monstrous cell with a nuclear invagination represents a degenerative cell usually seen in aging seminal vesicles.
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Reference: Seminal vesicles / ejaculatory duct
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Reference: Seminal vesicles / ejaculatory duct
