Ejaculatory Behavior and Seminal Vesicle Size During Radical Prostatectomy
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Recent Ejaculation, Preoperative Abstinence.
- Who it may be relevant to
- Registry conditions: Prostate Cancer Patients Undergoing Radical Prostatectomy. Basic parameters: from 18 years · Male.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Taiwan
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Impact of Preoperative Ejaculation or Abstinence on Seminal Vesicle Size and Intraoperative Dissection Parameters During Radical Prostatectomy: A Randomized Controlled Trial
Overview
The goal of this clinical trial is to learn if recent ejaculation or abstinence before surgery affects seminal vesicle size and dissection-related surgical factors in adult men with prostate cancer undergoing radical prostatectomy. The main questions it aims to answer are: Does ejaculation within 36 hours before surgery reduce seminal vesicle size compared to abstinence of 72 hours or more? Does seminal vesicle size affect the ease or difficulty of surgical dissection during radical prostatectomy? Researchers will compare an ejaculation group to an abstinence group to see if seminal vesicle volume and intraoperative surgical parameters differ between them. Participants will: Follow specific instructions to either ejaculate or abstain before surgery Undergo a transrectal ultrasound (TRUS) to measure seminal vesicle size after anesthesia but before surgery Have their surgical dissection time and difficulty rated by the operating surgeon
Detailed description
Radical prostatectomy (RP) remains a cornerstone treatment for localized prostate cancer. During RP, the anatomical dissection of seminal vesicles (SVs) can be challenging, and SV volume may influence intraoperative visibility, dissection ease, and the risk of complications.
Recent imaging studies suggest that ejaculatory activity significantly affects SV size. In particular, abstinence has been associated with larger SV volumes on MRI and TRUS, while ejaculation may lead to temporary SV shrinkage. These physiological changes, though well-documented radiologically, have not been systematically studied in a surgical setting.
This trial aims to explore whether ejaculatory behavior in the days before RP alters the surgical anatomy and impacts dissection-related metrics. Forty adult male patients with biopsy-confirmed prostate cancer, scheduled for RP, will be randomized in a 1:1 ratio into two groups:
Ejaculation group: At least one ejaculation within 36 hours preoperatively.
Abstinence group: No ejaculation for ≥72 hours before surgery.
Under anesthesia and prior to surgery, transrectal ultrasound (TRUS) will be performed to measure bilateral SV dimensions. The average volume will serve as the primary endpoint. Intraoperative outcomes include dissection time, visual clarity, and perceived difficulty rated by the primary surgeon using a Likert scale. SV volume from final pathology reports will also be collected and compared.
This is a low-risk, behavior-based interventional study involving no experimental drug or device. The main purpose is to assess whether preoperative sexual behavior can be optimized to improve surgical planning and efficiency. Alpha-blocker usage and other potential confounders will be documented and adjusted for in the analysis.
If significant anatomical or procedural differences are observed, findings from this study may inform future multicenter research and guide preoperative patient counseling for RP.
Interventions
- Behavioral Recent Ejaculation
Participants are instructed to ejaculate at least once within 36 hours prior to radical prostatectomy. This behavioral intervention is used to evaluate its effect on seminal vesicle volume and intraoperative dissection parameters. - Behavioral Preoperative Abstinence
Participants are instructed to abstain from ejaculation for at least 72 hours prior to radical prostatectomy. This behavioral intervention is used to assess whether prolonged seminal vesicle filling affects intraoperative anatomy and dissection.
Primary outcome measures
- Seminal vesicle volume measured by preoperative transrectal ultrasound (TRUS) [Time frame: 12-14 hours before surgery (afternoon prior to operation)]
Secondary outcome measures (4)
- Dissection time of seminal vesicles during radical prostatectomy [Time frame: During surgery (intraoperative)]
- Surgical difficulty score of seminal vesicle dissection [Time frame: Immediately after SV dissection during surgery]
- Intraoperative visual clarity score of seminal vesicles [Time frame: During SV dissection, intraoperatively]
- Seminal vesicle volume reported in postoperative pathology [Time frame: Within 7 days after surgery (postoperative pathology report)]
Eligibility criteria
Inclusion criteria
- Male patients aged 18 years or older
- Histologically confirmed prostate cancer
- Scheduled for radical prostatectomy
- Able and willing to comply with assigned ejaculation or abstinence protocol
- Willing to complete preoperative questionnaire
- Willing to undergo transrectal ultrasound (TRUS) 12-14 hours before surgery
- Able to understand and sign informed consent
Exclusion criteria
- Prior bilateral seminal vesicle resection or congenital absence of seminal vesicles
- Anatomical abnormalities preventing SV identification
- Hormone therapy within 6 months before surgery
- Inability to recall ejaculation history in the past 3 days
- Inability to follow behavioral instructions or TRUS protocol
- Severe anorectal disease or history of anorectal surgery preventing TRUS
- Cognitive or psychiatric conditions impairing informed consent
- Incomplete data or poor-quality imaging
- Prior prostate cancer treatment
- Belonging to a vulnerable population (e.g., minors, prisoners, pregnant individuals, cognitively impaired, etc.)
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Single blind
- Primary purpose
- Health services research
Study locations
Taiwan · 1 center
- National Taiwan University Cancer Center — Taipei
Publications
- Medved M, Sammet S, Yousuf A, Oto A. MR imaging of the prostate and adjacent anatomic structures before, during, and after ejaculation: qualitative and quantitative evaluation. Radiology. 2014 May;271(2):452-60. doi: 10.1148/radiol.14131374. Epub 2014 Feb 1. PMID 24495265
- Shin T, Kaji Y, Shukuya T, Nozaki M, Soh S, Okada H. Significant changes of T2 value in the peripheral zone and seminal vesicles after ejaculation. Eur Radiol. 2018 Mar;28(3):1009-1015. doi: 10.1007/s00330-017-5077-4. Epub 2017 Oct 6. PMID 28986624
- Yuruk E, Pastuszak AW, Suggs JM 3rd, Colakerol A, Serefoglu EC. The association between seminal vesicle size and duration of abstinence from ejaculation. Andrologia. 2017 Sep;49(7):10.1111/and.12707. doi: 10.1111/and.12707. Epub 2016 Sep 23. PMID 27660049
Identifiers
NCT: NCT07243795 · 202507191RINA