Endorectal MRI of Prostatic and Periprostatic Cystic Lesions and Their Mimics

Seminal vesicles in focus: An illustrated overview

Seminal vesicles play a crucial role in the male reproductive system, as they are responsible for secreting a fluid that forms most of the ejaculate. Seminal vesicles' pathology can present with non-specific symptoms, making imaging diagnosis essential for proper patient management. Various imaging modalities can be used to evaluate these glands, with MRI beneficial in illustrating the spectrum of seminal vesicle disease. Typical seminal vesicles appear as elongated fluid-containing structures, but congenital anomalies, inflammatory conditions, and neoplastic disorders can alter their appearance. Furthermore, differentiating mimics from actual pathology can be challenging but crucial for proper management. This article aims to provide an overview of the typical imaging appearance of the seminal vesicles and illustrate the principal imaging characteristics of conditions involving these structures. It will review the imaging characteristics of common and uncommon lesions involving the seminal vesicles by exploring congenital, infectious, and neoplastic in detail. As the seminal vesicles are often evaluated incidentally during prostate imaging, radiologists should be aware of the variability of normal findings and recognize the principal pathologies affecting these structures to ensure proper patient management.

Prostatic Utricle Cysts as a Potential Pitfall in PSMA PET/CT Interpretation

ABSTRACT

A 60-year-old man with T2aN0M0 prostate cancer underwent intensity-modulated radiotherapy targeting the prostate and seminal vesicles. Experiencing biochemical recurrence after 6 years, 68Ga-PSMA-11 PET/CT revealed focal radioactivity in the posterior midline of the prostate, identified as a prostatic utricle cyst on subsequent MRI. Similar findings appeared in a previous 18F-piflufolastat PET/CT, with negative biopsy results. The patient then received intensity-modulated radiotherapy directed to 2 PSMA-avid pelvic nodes and leuprolide acetate, achieving an undetectable PSA in 4 months. This case highlights a potential pitfall in PSMA PET interpretation associated with prostatic utricle cysts.

Cystic Pelvic Masses in Men: A Presentation of Uncommon Cases and a Literature Review

Unclear cystic masses in the pelvis in male patients are a rare situation and could be of benign or malignant origin. The underlying diseases demand for specific diagnostic and therapeutic approaches. We present a case series of 3 male patients with different clinical symptoms (perineal pain, urinary retention and a large scrotal cyst) related to cystic lesions in the pelvic region. On all patients initial histopathological workup was unclear. All patients underwent surgery with complete resection of the tumor which revealed a broad spectrum of histopathological findings: unusual form of cystic adenocarcinoma of the prostate, malignant transformation of a dysontogenetic cyst, and finally a very rare diagnosis of a malignant tumor of the Cowper gland. This case series and literature review provide clues for a possible diagnostic and therapeutic approach in the case of unclear pelvic cystic masses and could support urologists during the therapy selection in the future.

Should asymptomatic small anteriorly located midline prostatic cyst in young adults be treated surgically or conservatively? A case report and review of the literature

Background

Prostatic cysts are uncommon, typically asymptomatic and discovered by chance during imaging. Prostatic cysts in the midline are less prevalent and primarily seen in the posterior aspect of the prostate.

Case presentation

We describe a case of a 32-year-old man with a complaint of left loin pain and a little sensation of pelvic discomfort. Ultrasound was done revealing small pelvic cystic structure related to urinary bladder base and neck with possibility to be prostatic in origin. Transrectal ultrasound and pelvic magnetic resonance imaging were done and showed an anteriorly located midline prostatic cyst protruding into the bladder lumen, with no communication with the urethra on conventional ascending urethrogram.

Conclusion

The rare relationship between the cyst, bladder neck, and prostate make this case to some extent unique and further interesting. To our best knowledge, this is the eighth documented case in the literature to describe an anteriorly located midline intraprostatic cyst projecting at the bladder neck and base with illustration of different plans of treatment.

Congenital cysts of the lower male genitourinary tract: a disorder with various treatment approaches and pitfalls-case report

BACKGROUND

The cysts of the male pelvic floor represent a rare clinical entity. Their origin is linked to an altered development of paramesonephric and mesonephric ducts during embryogenesis.

CASE PRESENTATION

We report our experience regarding two patients presenting cysts of the ejaculatory system treated with open and mini-invasive surgery. The patients referred to our clinic with nonspecific symptoms and the diagnosis was obtained by radiological investigations. The patient treated with an open approach developed a pelvic purulent collection and a fistula of the prostatic urethra, managed with surgical drainage and prolonged bladder catheterization. On the other hand, the patient treated with laparoscopic approach did not develop any complications. No sexual or ejaculatory disorders were reported.

CONCLUSIONS

Patients with congenital cysts of the pelvic floor must be adequately informed about the risks and benefits of surgery and a careful counseling is mandatory before surgery. Treatment is recommended for symptomatic patients and an endoscopic approach is associated with a high rate of recurrence. A laparoscopic approach, when possible, is desirable.

More Than Detection of Adenocarcinoma - Indications and Findings in Prostate MRI in Benign Prostatic Disorders

BACKGROUND

 Multiparametric MRI of the prostate has become a fundamental tool in the diagnostic pathway for prostate cancer and is recommended before (or after negative) biopsy to guide biopsy and increase accuracy, as a staging examination (high-risk setting), and prior to inclusion into active surveillance. Despite this main field of application, prostate MRI can be utilized to obtain information in a variety of benign disorders of the prostate.

METHODS

 Systematic bibliographical research with extraction of studies, national (German) as well as international guidelines (EAU, AUA), and consensus reports on MRI of benign disorders of the prostate was performed. Indications and imaging findings of prostate MRI were identified for a) imaging the enlarged prostate, b) prostate MRI in prostatic artery embolization, c) imaging in prostatitis and d) imaging in congenital anomalies.

RESULTS AND CONCLUSIONS

 Different phenotypes of the enlarged prostate that partly correlate with severity of symptoms are discussed. We provide an overview of the different types of prostatitis and possible imaging findings, highlighting abscesses as a severe complication. The most common congenital anomalies of the prostate are utricular cysts, whereas anomalies like aplasia, hypoplasia, and ectopia are rare disorders. Knowledge of indications for imaging and imaging appearance of these conditions may improve patient care and enhance differential diagnosis.

KEY POINTS

  · Current guidelines do not implement indications for mpMRI apart from prostate carcinoma.. · MRI can distinguish different anatomical phenotypes of prostatic enlargement.. · Prostatic artery embolization represents a valuable treatment option in cases of symptomatic benign prostatic enlargement.. · Different forms of prostatitis exist and may mimic prostate carcinoma in MRI.. · MRI can be used to evaluate anatomical prostate anomalies..

CITATION FORMAT

· Oerther B, Sigle A, Franiel T et al. More Than Detection of Adenocarcinoma - Indications and Findings in Prostate MRI in Benign Prostatic Disorders. Fortschr Röntgenstr 2022; DOI: 10.1055/a-1719-1463.

Cystic Prostatic Carcinoma - A Clinical Case and Literature Review

Cystic formations in the prostate are quite common, but the vast majority are benign. The cystic form of prostate adenocarcinoma can present unexpected symptoms, and management can be difficult because of the local advanced stage of the disease. A unique feature of this case is the surgical local cancer treatment. In this clinical case, we describe the literature surrounding this rare form of neoplasm. We present a clinical case of a rare form of prostate cancer in a 71-year-old male who was admitted to ER with acute urinary retention. A huge obstructing prostatic cyst was revealed. After successful trial-without-catheter, the patient underwent transperineal cyst draining and this restored urination. PSAt was increased up to 55 ng/mL. The cystic wall biopsy revealed adenocarcinoma with a Gleason score of 8 (4+4) (Gleason Group IV), and distant metastasis was noticed with PSMA PET/CT. The patient started androgen deprivation therapy (ADT) with excellent PSA dynamics in three months. Because of lower urinary tract symptoms, he needed local treatment and underwent radical prostatectomy. A three-month follow-up demonstrated a common post-operative period, mild stress incontinence, and PSAt 0.004 ng/mL. Cystic prostatic carcinoma can manifest as urinary retention and be mistakenly taken for a benign obstructing prostate cyst. Despite the locally advanced tumor, it can be successfully treated locally in highly selected patients.

Incidental findings in and around the prostate on prostate MRI: a pictorial review

Prostate MRI has seen rapid growth in use in recent years as an advanced diagnostic modality to detect focal areas of clinically significant prostate cancer, to identify an area for targeted biopsy and to guide management and surveillance. The increase in use has also led to increased diagnosis of incidental lesions arising from structures around the prostate. These incidental findings may be related to the genitourinary system or non- genitourinary system and may have a benign aetiology which needs no additional follow-up, or it may require surveillance and management. The field of view in a multiparametric prostate MRI includes other pelvic organs, neurovascular bundles, bowel, lymph nodes and bones. Being familiar with standard MRI characteristics and a sound knowledge of anatomy of the prostate and surrounding structures can help in distinguishing normal anatomy from pathology. Given that patients undertaking a prostate MRI are usually a cohort with increased anxiety from their known or suspicion of prostate cancer, it is important that radiologists are familiar with these common incidental findings to minimise anxiety to the patient, have a well-informed discussion with the referring clinician and reduce costs associated with unnecessary further testing and follow-up of benign incidental findings. Additionally, being able to diagnose more serious incidental pathologies early can be life-saving and potentially significantly alter patient management.

MRI of prostatic urethral mucinous urothelial carcinoma: Expanding the differential diagnosis for T2 hyperintense prostatic masses

We report the case of a 66-year-old previously healthy man presenting with blood and mucus in his urine. Cystoscopy revealed a mass in the prostatic urethra, and endoscopic biopsy showed adenocarcinoma in situ with mucinous features. Endorectal multiparametric prostate MRI demonstrated a 1.9 cm T2 hyperintense mass in the peripheral zone of the left prostatic apex with extension into the urethral lumen. No diffusion restriction or early enhancement was seen in the mass. Radical prostatectomy was performed, and final pathology demonstrated a mucin-producing urothelial adenocarcinoma arising from the prostatic urethra. The peripheral zone T2 hyperintense abnormality correlated with abundant pools of mucin extending into the prostatic stroma and surrounded by neoplastic prostatic glandular cells. We conclude prostatic urethral mucinous urothelial carcinoma should be included in the differential diagnosis for T2 hyperintense prostatic masses.

Prostate Benign Diseases

Magnetic resonance imaging (MRI) has been increasingly used in the detection, localization, and staging of prostate cancer. Because of its excellent soft tissue contrast and multiplane imaging, it can be also very useful in the evaluation of benign prostate diseases. Prostatic benign disorders have a high prevalence, vastly represented by benign prostatic hyperplasia and prostatitis. On the contrary, benign prostatic neoplasms are extremely rare, represented by multilocular cystadenoma, leiomyomas, hemangioma, and granular cell tumor, although these uncommon tumors have been most encountered due to widespread use of MRI. Congenital prostatic anomalies are associated with defects in the development of the prostate embryology, including hypoplasia, ectopia, and vascular malformations, abnormalities rarely seen on cross-sectional imaging. Prostatic cysts are the most common development abnormalities and occasionally are related to clinical symptoms, mainly due to infection and hemorrhage. As with prostate cancer, multiparametric MRI is a reliable tool for the diagnosis and management of benign prostatic diseases as well, providing additional information such morphological changes of the prostate, more accurate prostatic measurements, and functional characteristics of nonmalignant prostatic lesions. In this review, we discuss MRI findings of these benign prostatic diseases.

Relationship of Seminal Megavesicles, Prostate Median Cysts, and Genotype in Autosomal Dominant Polycystic Kidney Disease

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) can involve prostate and seminal vesicles but the potential interrelationship of these findings and associations with PKD gene mutation locus and type is unknown.

PURPOSE

To determine the interrelationship of seminal megavesicles (seminal vesicles with lumen diameter > 10mm) and prostatic cysts in ADPKD and to determine whether there are associations with PKD gene mutations.

STUDY TYPE

Retrospective, case control.

POPULATION

Male ADPKD subjects (n = 92) with mutations in PKD1 (n = 71; 77%) or PKD2 (n = 21; 23%), and age/gender-matched controls without ADPKD (n = 92).

FIELD STRENGTH/SEQUENCE

1.5T, axial/coronal T₂ -weighted MR images.

ASSESSMENT

Reviewers blinded to genotype independently measured seminal vesicle lumen diameter and prevalence of cysts in prostate, kidney, and liver.

STATISTICAL TESTS

Nonparametric tests for group comparisons and univariate and multivariable logistic regression analyses to identify associations of megavesicles and prostate median cysts with mutations and renal/hepatic cyst burden.

RESULTS

Seminal megavesicles were found in 23 of 92 ADPKD (25%) subjects with PKD1 (22/71, 31%) or PKD2 (n = 1/21, 5%) mutations, but in only two control subjects (P < 0.0001). Prostate median cysts were found in 17/92 (18%) ADPKD subjects, compared with only 6/92 (7%) controls (P = 0.01), and were correlated with seminal vesicle diameters (ρ = 0.24, P = 0.02). Nonmedian prostate cyst prevalence was identical between ADPKD and controls (7/92, 8%). After adjusting for age, estimated glomerular filtration rate, and height-adjusted total kidney volume, ADPKD subjects with megavesicles were 10 times more likely to have a PKD1 than a PKD2 mutation. Among PKD1 subjects, seminal megavesicles occurred more frequently with nontruncating mutations with less severe kidney involvement.

DATA CONCLUSION

ADPKD is associated with prostate median cysts near ejaculatory ducts. These cysts correlate with seminal megavesicles (dilated to >10 mm) which predict a 10-fold greater likelihood of PKD1 vs. PKD2 mutation. Cysts elsewhere in the prostate are not related to ADPKD.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:894-903.

Hematospermia Evaluation at MR Imaging

Hematospermia is a challenging and anxiety-provoking condition that can manifest as a single episode or recur over the course of weeks to months. It is usually a benign self-limiting condition in younger sexually active males without a history of risk factors such as cancer, urogenital malformations, bleeding disorders, and their associated symptoms. However, patients with recurrent, refractory and painful hematospermia with associated symptoms, such as fever, pain, or weight loss, require evaluation through clinical assessment and noninvasive investigations to rule out underlying pathologic conditions such as ejaculatory obstruction, infectious and inflammatory causes, malignancy, vascular malformations, and systemic disorders that increase the risk of bleeding, especially when presenting in older men. If these investigations are negative, the patient should be reassured and treated accordingly. In the recent past, magnetic resonance (MR) imaging has assumed a major role in the investigation of hematospermia due to its excellent soft-tissue contrast and multiplanar capabilities. In this review, we will discuss the potential causes of hematospermia and its diagnostic workup, including pathophysiology, anatomic considerations, the imaging appearance of associated pathologic conditions, and management. (©)RSNA, 2016.

[3-Tesla MRI of rare large cystic prostate carcinoma]

Magnetic resonance imaging of rare cystic prostate cancers using multiparametric MRI (mp-MRI, 3 Tesla) shows, especially in solid tumor masses, the criteria of ESUR-MR classification with a PI-RADS >3 ("probably malignant"). In association with additional morphological evidence of intracystic hemorrhage and evidence of villous tumor nodules and irregular septa on the cyst wall, further malignancy criteria are met. MRI complementary to TRUS may be useful for targeted biopsy in solid tumor areas.

[Ejaculatory system cysts: a case report]

INTRODUCTION

Male pelvic floor cysts are a rare clinical entity that include: Wolffian duct remnants, Müllerian duct remnants, cysts of the seminal vesicles, prostate and ejaculatory duct/vas deferens cysts.


CASE REPORT

We report the clinical case of a 21-year-old male patient with a history of previous surgery in childhood and more precisely: partial colectomy for congenital megacolon, removal of dysplastic right kidney and subsequent surgical adhesiolysis for bowel obstruction.
 At 17, the patient was submitted to MRI for groin pain with an incidental finding of a cystic mass at the level of the right seminal vesicle. Consequently, a TUR-ED was performed at another urology unit, for a suspected seminal vesicle ectasia, without resolution of pain symptoms. The patient was referred to us for persistent genitourinary infections, ejaculation disorder and episodes of gross hematuria. An additional MRI confirmed the presence of a cystic mass of 5,5 cm with a suspected opening into prostatic urethra. Urethrocystoscopy and urethrocystography retrograde confirmed this anatomical communication. For the persistence of the symptoms we performed retropubic surgical exeresis of the mass, with a histopathological finding of benign cyst of the vas deferens.
 Two major postoperative complications were reported: a pelvic hematoma that required surgical exploration and a urinary extravasation at the level of prostatic urethra, which resolved with prolonged urethral catheterization.


CONCLUSIONS

Male pelvic floor cysts are a rare disease with a complex clinical and therapeutic management. A correct diagnosis is based on clinical signs and symptoms together with imaging studies of the pelvic region. The high risk of erectile dysfunction and ejaculatory disorders correlated to a surgical approach, recommend a treatment of these lesions only for symptomatic cases.

Cysts of the lower male genitourinary tract: embryologic and anatomic considerations and differential diagnosis

Cysts of the lower male genitourinary tract are uncommon and usually benign. These cysts have different anatomic origins and may be associated with a variety of genitourinary abnormalities and symptoms. Various complications may be associated with these cysts, such as urinary tract infection, pain, postvoiding incontinence, recurrent epididymitis, prostatitis, and hematospermia, and they may cause infertility. Understanding the embryologic development and normal anatomy of the lower male genitourinary tract can be helpful in evaluating these cysts and in tailoring an approach for developing a differential diagnosis. There are two main groups of cysts of the lower male genitourinary tract: intraprostatic cysts and extraprostatic cysts. Intraprostatic cysts can be further classified into median cysts (prostatic utricle cysts, müllerian duct cysts), paramedian cysts (ejaculatory duct cysts), and lateral cysts (prostatic retention cysts, cystic degeneration of benign prostatic hypertrophy, cysts associated with tumors, prostatic abscess). Extraprostatic cysts include cysts of the seminal vesicle, vas deferens, and Cowper duct. A variety of pathologic conditions can mimic these types of cysts, including ureterocele, defect resulting from transurethral resection of the prostate gland, bladder diverticulum, and hydroureter and ectopic insertion of ureter. Accurate diagnosis depends mainly on the anatomic location of the cyst. Magnetic resonance imaging and transrectal ultrasonography (US) are excellent for detecting and characterizing the nature and exact anatomic origin of these cysts. In addition, transrectal US can play an important therapeutic role in the management of cyst drainage and aspiration, as in cases of prostatic abscess.

An abnormally large prostatic utricle cyst associated with unilateral renal agenesis

Prostatic utricle cyst is an uncommon congenital disorder associated with urogenital anomalies. We present a case of an abnormally large prostatic utricle cyst filling the whole of the abdominal cavity with unilateral renal agenesis in an 8-year-old male child.

MRI of acquired posterior urethral diverticulum following surgery for anorectal malformations

BACKGROUND

Posterior urethral diverticulum (PUD) is one of the most common postoperative complications associated with anorectal malformation (ARM) correction.

OBJECTIVE

To describe our MRI protocol for evaluating acquired PUD following ARM surgery, and associated imaging findings.

MATERIALS AND METHODS

Two radiologists retrospectively reviewed 61 pelvic MRI examinations performed for postoperative ARM for PUD identification and characteristics. Associated clinical, operative and cystoscopy reports were also reviewed and compared to MRI.

RESULTS

An abnormal retrourethral focus suspicious for PUD was identified at MRI in 13 patients. Ten of these patients underwent subsequent surgery or cystoscopy, and PUD was confirmed in five. All of the confirmed PUD cases appeared as cystic lesions that were at least 1 cm in diameter in two imaging planes. Four of the false-positive cases were punctate retrourethral foci that were visible only on a single MRI plane. One patient had a seminal vesical cyst mimicking a PUD.

CONCLUSION

Pelvic MRI can be a useful tool in the postoperative assessment of suspected PUD associated with ARM. Radiologists should have a high clinical suspicion for a postoperative PUD when a cystic lesion posterior to the bladder/posterior urethra is encountered on two imaging planes in these patients.

MRI signal intensity based B-spline nonrigid registration for pre- and intraoperative imaging during prostate brachytherapy

PURPOSE

To apply an intensity-based nonrigid registration algorithm to MRI-guided prostate brachytherapy clinical data and to assess its accuracy.

MATERIALS AND METHODS

A nonrigid registration of preoperative MRI to intraoperative MRI images was carried out in 16 cases using a Basis-Spline algorithm in a retrospective manner. The registration was assessed qualitatively by experts' visual inspection and quantitatively by measuring the Dice similarity coefficient (DSC) for total gland (TG), central gland (CG), and peripheral zone (PZ), the mutual information (MI) metric, and the fiducial registration error (FRE) between corresponding anatomical landmarks for both the nonrigid and a rigid registration method.

RESULTS

All 16 cases were successfully registered in less than 5 min. After the nonrigid registration, DSC values for TG, CG, PZ were 0.91, 0.89, 0.79, respectively, the MI metric was -0.19 +/- 0.07 and FRE presented a value of 2.3 +/- 1.8 mm. All the metrics were significantly better than in the case of rigid registration, as determined by one-sided t-tests.

CONCLUSION

The intensity-based nonrigid registration method using clinical data was demonstrated to be feasible and showed statistically improved metrics when compare to only rigid registration. The method is a valuable tool to integrate pre- and intraoperative images for brachytherapy.

Endorectal magnetic resonance imaging in persistent hemospermia

OBJECTIVE

To present the spectrum of abnormalities found at endorectal magnetic resonance imaging (E-MRI), in patients with persistent hemospermia.

MATERIALS AND METHODS

A review of E-MRI findings observed in 86 patients with persistent hemospermia was performed and results compared with those reported in the literature. Follow-up was possible in 37 of 86 (43%) patients with hemospermia.

RESULTS

E-MRI showed abnormal findings in 52 of 86 (60%) patients with hemospermia. These findings were: a) hemorrhagic seminal vesicle and ejaculatory duct, isolated (n = 11 or 21%) or associated with complicated midline prostatic cyst (n = 10 or 19.0%); b) hemorrhagic chronic seminal vesiculitis, isolated (n = 14 or 27%) or associated with calculi within dilated ejaculatory ducts (n = 2 or 4 %); c) hemorrhagic seminal vesicle associated with calculi within dilated ejaculatory duct (n = 4 or 7.7%) or within seminal vesicle (n = 4 or 7.7%); d) non-complicated midline prostatic cyst (n = 6 or 11.5%); and e) prostate cancer (n = 1 or 2%). Successful treatment was more frequent in patients with chronic inflammatory and/or obstructive abnormalities.

CONCLUSION

E-MRI should be considered the modality of choice, for the evaluation of patients with persistent hemospermia.