EndometriosisAppENDNCT07823777
Appendectomy as an Adjunct Procedure in Endometriosis Surgery
A study testing Appendectomy in people with Endometriosis, run by Mount Sinai Hospital, Canada.
Trial summary
This study addresses a common but unresolved clinical decision in endometriosis surgery: whether to perform an adjunct appendectomy. Currently, this decision is often based on individual surgeon judgement or institutional practice rather than robust evidence. Read more about this study
- Who is it for?
- Ages 18 to 50 years, women only
- Conditions the study is for
- Endometriosis
- What is being tested?
- Appendectomy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 240 participants
- Where
- No sites listed yet
- Study dates
- Apr 2027to Apr 2029
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 50 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- Age 18-50 years
- Endometriosis diagnosis based on imaging or prior surgical findings
- Baseline pain above 3 on the Numerical Rating Scale (NRS)
- Undergoing surgical excision of endometriosis only, with at least one remaining ovary
Who cannot join
- Abnormal appearing appendix on imaging or intraoperatively
- No endometriosis seen at the time of surgery
- Previous appendectomy
- Menopausal
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Appendectomy as an Adjunct Procedure in Endometriosis Surgery (AppEND)
This study addresses a common but unresolved clinical decision in endometriosis surgery: whether to perform an adjunct appendectomy. Currently, this decision is often based on individual surgeon judgement or institutional practice rather than robust evidence.
This randomized controlled study aims to determine if removing a normal appearing appendix at the time of endometriosis surgery impacts post-operative recurrence of pelvic pain and endometriotic lesions at 12 months. Secondary outcomes include pathology of the appendix and complication rate of the procedure.
Read more
Participants will be randomized to appendectomy or no appendectomy at the time of their planned endometriosis surgery. The study also includes an observational cohort that participants may opt to join if they do not wish to be randomized.
Data are expected to guide surgical decision-making and contribute to the development of standardized surgical guidelines.
Read the detailed description
Endometriosis is a chronic inflammatory disease characterized by the growth of endometrial-like tissue outside the uterine cavity, affecting approximately 1 in 10 women and those assigned female at birth during reproductive years. Surgical excision is a cornerstone of endometriosis disease management, particularly in patients with refractory pain, advanced disease, infertility, bowel or urinary tract involvement, or diagnostic uncertainty. However, outcomes are highly variable due to significant variability in surgical approach, underscoring the need for high quality, prospective evidence to optimize surgical intervention.
Appendiceal involvement presents such an opportunity for optimization, which is estimated to impact anywhere from 10-50% of patients in this population. Currently, only appendices that are visually abnormal at the time of surgery are removed. Existing literature, limited to retrospective data, suggests that the addition of appendectomy at the time of endometriosis surgery decreases the risk of postoperative pain and disease recurrence in patients who have received surgical management, regardless of the visual appearance of the appendix.
Notably, visual assessment of the appendix and confirmation of histopathologic appendiceal involvement are not found to be well-correlated.
At this time, there is a lack of quality prospective data to support implementation of adjunct appendectomy into surgical practice. This study aims to bridge this gap by providing the evidence needed to standardize surgical decision-making.
This randomized controlled study will enroll eligible participants between the ages of 18-50 (pre-menopausal), who will undergo laparoscopic or robotic-assisted excision of endometriosis performed by the Minimally Invasive Surgery (MIS) team at Mount Sinai Hospital in Toronto, ON. If the appendix appears normal intraoperatively, the surgeon will proceed with randomized allocation to either appendectomy or no appendectomy. Participants will remain blinded through follow-up, including validated ENDOPAIN-4D questionnaires administered at 6 and 12 months post-operatively and an endometriosis mapping ultrasound at 12 months post-op.
Additional outcomes will assess whether the risk of intra- and post-surgical complications increase with the addition of an appendectomy compared to laparoscopy alone. Data will also be used to evaluate the prevalence of various appendiceal pathologies, including endometriosis- and non-endometriosis-related.
If a participant is unwilling to be randomized but still wishes to participate, they will be invited to join the observational cohort. Participants in this arm will be given the option of whether or not the appendix should be removed during surgery, should it appear normal, aligning with current standard of care. Participants in this arm will undergo all follow-up milestones in an unblinded manner.
The results of this study will be submitted for publication and for presentation at relevant conferences.
- Conditions
- Endometriosis
- Being tested
- Appendectomy, Standard of Care (SOC)
- Keywords
- Appendectomy
- Medical subject headings
- Endometriosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
AppendectomyProcedure or surgery
Removal of the appendix at the time of endometriosis surgery
Standard of Care (SOC)Procedure or surgery
If the appendix appears normal during surgery it will not be removed
| Study group | Role | What they receive |
|---|---|---|
| Appendectomy | Experimental | Participants randomized to have their appendix removed Receives: Procedure: Appendectomy |
| No appendectomy | Active comparator | Participants randomized to not have their appendix removed Receives: Procedure: Standard of Care (SOC) |
| Observational Cohort | No intervention | Participants will choose whether or not to have their appendix removed during surgery if it appears normal |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in pelvic pain severity
Change from baseline to 1 year in post-operative pain severity as measured by the ENDOPAIN-4D questionnaire (lower score = less pain)
Measured: 1 year
Rate of endometriosis lesion recurrence
Rates of recurrence of endometriosis lesions based on 12-month endometriosis mapping ultrasound
Measured: 1 year
Secondary outcomes (9)
Change in pelvic pain severity
Change from baseline to 6 months in post-operative pain severity as measured by the ENDOPAIN-4D questionnaire (lower score = less pain)
Measured: 6 months
Change in pelvic pain severity
Change from baseline to 6 months in post-operative pain severity as measured by the Numerical Rating Scale (NRS; lower score = less pain)
Measured: 6 months
Change in pelvic pain severity
Change from baseline to 1 year in post-operative pain severity as measured by the Numerical Rating Scale (NRS; lower score = less pain)
Measured: 1 year
Postoperative complications
Postoperative analgesia use, sleep disturbances, and lifestyle impact at 30 days, reported by participant
Measured: 30 days
Rate of positive appendiceal pathology
Pathology findings from appendix analysis
Measured: 30 days
Types of appendiceal pathology
Types of endometriosis and non-endometriosis appendiceal pathology identified via histopathological analysis of removed appendices
Measured: 30 days
Operative time
Duration of surgery
Measured: During surgery
Postoperative analgesia use
Frequency of analgesic use post-surgery to manage pain
Measured: 1 year
Percentage of eligible participants willing to be randomized
Of those who met study criteria, what percentage were willing to be randomized
Measured: 1 year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Sep 2026
- Study startApr 2027 (estimated)
- Primary completionApr 2028 (estimated)
- Study completionApr 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for EndometriosisStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 240 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Mount Sinai Hospital, Canada
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Olga Bougie, Mount Sinai Hospital, Canada
- Investigators
- Olga Bougie, MD, Principal investigator, MOUNT SINAI HOSPITAL
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07823777
- Sponsor's protocol ID
- 1597
- Acronym
- AppEND
- Status last verified
- Sep 2026
- First submitted
- 18 Feb 2026
- Last updated
- 16 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 16 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Appendectomy as an Adjunct Procedure in Endometriosis Surgery (AppEND)
- ClinicalTrials.gov ID
- NCT07823777
- Acronym / sponsor ID
- AppEND / 1597
- Conditions
- Endometriosis
- Keywords
- Appendectomy
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 240 participants (estimated)
- Lead sponsor
- Mount Sinai Hospital, CanadaUniversity, hospital or other
- Study start
- Apr 2027 (estimated)
- Primary completion
- Apr 2028 (estimated)
- Study completion
- Apr 2029 (estimated)
- First posted
- 16 Sep 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study addresses a common but unresolved clinical decision in endometriosis surgery: whether to perform an adjunct appendectomy. Currently, this decision is often based on individual surgeon judgement or institutional practice rather than robust evidence.
This randomized controlled study aims to determine if removing a normal appearing appendix at the time of endometriosis surgery impacts post-operative recurrence of pelvic pain and endometriotic lesions at 12 months. Secondary outcomes include pathology of the appendix and complication rate of the procedure.
Participants will be randomized to appendectomy or no appendectomy at the time of their planned endometriosis surgery. The study also includes an observational cohort that participants may opt to join if they do not wish to be randomized.
Data are expected to guide surgical decision-making and contribute to the development of standardized surgical guidelines.
Detailed description
Endometriosis is a chronic inflammatory disease characterized by the growth of endometrial-like tissue outside the uterine cavity, affecting approximately 1 in 10 women and those assigned female at birth during reproductive years. Surgical excision is a cornerstone of endometriosis disease management, particularly in patients with refractory pain, advanced disease, infertility, bowel or urinary tract involvement, or diagnostic uncertainty. However, outcomes are highly variable due to significant variability in surgical approach, underscoring the need for high quality, prospective evidence to optimize surgical intervention.
Appendiceal involvement presents such an opportunity for optimization, which is estimated to impact anywhere from 10-50% of patients in this population. Currently, only appendices that are visually abnormal at the time of surgery are removed. Existing literature, limited to retrospective data, suggests that the addition of appendectomy at the time of endometriosis surgery decreases the risk of postoperative pain and disease recurrence in patients who have received surgical management, regardless of the visual appearance of the appendix.
Notably, visual assessment of the appendix and confirmation of histopathologic appendiceal involvement are not found to be well-correlated.
At this time, there is a lack of quality prospective data to support implementation of adjunct appendectomy into surgical practice. This study aims to bridge this gap by providing the evidence needed to standardize surgical decision-making.
This randomized controlled study will enroll eligible participants between the ages of 18-50 (pre-menopausal), who will undergo laparoscopic or robotic-assisted excision of endometriosis performed by the Minimally Invasive Surgery (MIS) team at Mount Sinai Hospital in Toronto, ON. If the appendix appears normal intraoperatively, the surgeon will proceed with randomized allocation to either appendectomy or no appendectomy. Participants will remain blinded through follow-up, including validated ENDOPAIN-4D questionnaires administered at 6 and 12 months post-operatively and an endometriosis mapping ultrasound at 12 months post-op.
Additional outcomes will assess whether the risk of intra- and post-surgical complications increase with the addition of an appendectomy compared to laparoscopy alone. Data will also be used to evaluate the prevalence of various appendiceal pathologies, including endometriosis- and non-endometriosis-related.
If a participant is unwilling to be randomized but still wishes to participate, they will be invited to join the observational cohort. Participants in this arm will be given the option of whether or not the appendix should be removed during surgery, should it appear normal, aligning with current standard of care. Participants in this arm will undergo all follow-up milestones in an unblinded manner.
The results of this study will be submitted for publication and for presentation at relevant conferences.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Appendectomy | Experimental | Procedure: AppendectomyParticipants randomized to have their appendix removed |
| No appendectomy | Active comparator | Procedure: Standard of Care (SOC)Participants randomized to not have their appendix removed |
| Observational Cohort | No intervention | –Participants will choose whether or not to have their appendix removed during surgery if it appears normal |
Who may qualify
- Ages
- 18 to 50 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Age 18-50 years
- Endometriosis diagnosis based on imaging or prior surgical findings
- Baseline pain above 3 on the Numerical Rating Scale (NRS)
- Undergoing surgical excision of endometriosis only, with at least one remaining ovary
Key exclusion criteria (4 listed)
- Abnormal appearing appendix on imaging or intraoperatively
- No endometriosis seen at the time of surgery
- Previous appendectomy
- Menopausal
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| AppendectomyRemoval of the appendix at the time of endometriosis surgery | Procedure or surgery | Appendectomy |
| Standard of Care (SOC)If the appendix appears normal during surgery it will not be removed | Procedure or surgery | No appendectomy |
Primary outcome
Change in pelvic pain severity
Time frame: 1 year
Change from baseline to 1 year in post-operative pain severity as measured by the ENDOPAIN-4D questionnaire (lower score = less pain)
Rate of endometriosis lesion recurrence
Time frame: 1 year
Rates of recurrence of endometriosis lesions based on 12-month endometriosis mapping ultrasound
9 secondary outcomes
Change in pelvic pain severity
Time frame: 6 months
Change in pelvic pain severity
Time frame: 6 months
Change in pelvic pain severity
Time frame: 1 year
Postoperative complications
Time frame: 30 days
Rate of positive appendiceal pathology
Time frame: 30 days
Types of appendiceal pathology
Time frame: 30 days
Operative time
Time frame: During surgery
Postoperative analgesia use
Time frame: 1 year
Percentage of eligible participants willing to be randomized
Time frame: 1 year
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Sep 2026.
- Individual participant dataSharing planned: No
Related trials for Endometriosis
RecruitingPhase 4
Estetrol/Drospirenone to Reduce the Average Size of Endometriomas
Ovarian Endometrioma, Endometrioma
Not yet recruitingPhase 2
PRECISION-E2: Teverelix in Women With Endometriosis - Pharmacodynamics, Safety and Precision Medicine Correlates
Endometriosis Pelvic, Endometriosis Ovaries
Recruiting
Evaluating the Feasibility of elleFA App Implementation
Endometriosis
Recruiting
Dietary Intervention to Improve Fertility in Women With Endometriosis Undergoing IVF
Endometriosis
RecruitingPhase 1
Phase Ia Trial of HHK001 Compared With Enantone in Patients With Endometriosis
Endometriosis
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Olga Bougie, MD principal investigator
MOUNT SINAI HOSPITAL
Questions about this trial
What is this clinical trial studying?
A study testing Appendectomy in people with Endometriosis, run by Mount Sinai Hospital, Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 16 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Research Coordinator (416-586-8800 ext. 5526, tbd@sinaihealth.ca), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in pelvic pain severity (time frame: 1 year). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Sep 2026.