Appendix AbscessPeriAPPAC-TNCT04634448
The Prevalence of Appendiceal Tumours in Periappendicular Abscess
A study testing Interval appendectomy and Follow-up MRI at 1 year in people with Appendix Abscess and Appendicitis, run by Turku University Hospital.
Trial summary
Complicated and uncomplicated appendicitis follow different epidemiological trends also suggesting different pathophysiology behind these two different forms of appendicitis. In 3-10% of patients complicated acute appendicitis is enclosed by formation of a circumscribed periappendicular abscess. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Appendix Abscess, Appendicitis, Appendix Mass
- What is being tested?
- Interval appendectomy and Follow-up MRI at 1 year
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 400 participants
- Where
- No sites listed yet
- Study dates
- 1 Dec 2020to 31 Dec 2035
- 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 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- periappendiceal abscess proven by CT, Mri or US
Who cannot join
- patient declines to participate, complicated appendicitis without periappendiceal abscess
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
Jenny Alajääski, MD contact
About this study
Official title: The Prevalence of Appendiceal Tumours in Patients Presenting With a Periappendicular Abscess - A Nationwide Prospective Cohort Study
Complicated and uncomplicated appendicitis follow different epidemiological trends also suggesting different pathophysiology behind these two different forms of appendicitis. In 3-10% of patients complicated acute appendicitis is enclosed by formation of a circumscribed periappendicular abscess. The clinically established practice of antibiotic therapy and drainage, if necessary, has been shown safe and effective, allowing the acute inflammatory process to subside in more than 90% of cases without surgery. The need of subsequent interval appendectomy has been questioned with appendicitis recurrence risk varying between 5-26%.
During trial enrollment in our randomized Peri-APPAC trial based on the interim analysis results with 17% appendiceal tumor rate in the study population, the trial was prematurely terminated based on ethical concerns. All the follow-up group patients were re-evaluated and surgery was offered and recommended to all follow-up group patients. After this assessment and additional appendectomies, two more tumors were diagnosed resulting in neoplasm rate of 20% in the whole study group all diagnosed in patients over 40 years and the neoplasm rate in patients over 40 years was 29%.
Read more
Based on high appendiceal tumor rate in patients over 40 years, the appendiceal neoplasm rate needs to be further evaluated in prospective patient cohorts undergoing interval appendectomy as interval appendectomy is generally well tolerated and obliterates the risk of missing a possible tumor. In a recent systematic review of retrospective cohort studies with 13.244 acute appendicitis patients the overall appendiceal tumor rate was 1% after appendectomy, but in patients presenting with appendiceal inflammatory mass the neoplasm rate varied from 10% to 29%.
This nationwide prospective multicenter cohort study is designed to assess the prevalence of appendiceal tumors associated with a periappendicular abscess. All consecutive patients presenting with a periappendicular abscess are recommended to undergo interval appendectomy after initial conservative treatment with antibiotic therapy and drainage, if necessary. All patients older than 35 years will undergo laparoscopic interval appendectomy at 2 to 3 months and this is also recommended for the patients between 18 and 35 years of age. Asymptomatic patients under 35 years not willing to undergo interval appendectomy, will undergo a follow-up MRI at 1 year after the initial non-operative treatment.
Read the detailed description
Complicated and uncomplicated appendicitis follow different epidemiological trends also suggesting different pathophysiology behind these two different forms of appendicitis. In 3-10% of patients complicated acute appendicitis is enclosed by formation of a circumscribed periappendicular abscess. The clinically established practice of antibiotic therapy and drainage, if necessary, has been shown safe and effective, allowing the acute inflammatory process to subside in more than 90% of cases without surgery. The need of subsequent interval appendectomy has been questioned with appendicitis recurrence risk varying between 5-26%.
During trial enrollment in our randomized Peri-APPAC trial, the high incidence of appendiceal tumors in the study population alarmed the researchers. Based on the interim analysis results with 17% appendiceal tumor rate in the study population, the trial was prematurely terminated based on ethical concerns. All the follow-up group patients were re-evaluated and surgery was offered and recommended to all follow-up group patients. After this assessment and additional appendectomies, two more tumors were diagnosed resulting in neoplasm rate of 20% in the whole study group all diagnosed in patients over 40 years and the neoplasm rate in patients over 40 years was 29%.
Based on high appendiceal tumor rate in patients over 40 years, the appendiceal neoplasm rate needs to be further evaluated in prospective patient cohorts undergoing interval appendectomy as interval appendectomy is generally well tolerated and obliterates the risk of missing a possible tumor. In a recent systematic review of retrospective cohort studies with 13.244 acute appendicitis patients the overall appendiceal tumor rate was 1% after appendectomy, but in patients presenting with appendiceal inflammatory mass the neoplasm rate varied from 10% to 29%.
This nationwide prospective multicenter cohort study is designed to assess the prevalence of appendiceal tumors associated with a periappendicular abscess. All of the study hospitals will have a common clinical protocol of recommending interval appendectomy to all patients presenting with a periappendicular abscess after initial conservative treatment with antibiotic therapy and drainage, if necessary. Considering the high rate of appendiceal neoplasms, all patients older than 35 years will undergo laparoscopic interval appendectomy at 2 to 3 months after the successful initial non-operative treatment and this is also recommended for the patients between 18 and 35 years of age. Asymptomatic patients under 35 years not willing to undergo interval appendectomy, will undergo a follow-up MRI at 1 year after the initial non-operative treatment.
- Conditions
- Appendix Abscess, Appendicitis, Appendix Mass, Appendix Cancer, Appendix Nec, Appendix Tumor
- Being tested
- Interval appendectomy, Follow-up MRI at 1 year
- Medical subject headings
- Appendicitis, Appendiceal Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Interval appendectomyProcedure or surgery
interval appendectomy at 2 to 3 months after the initial non-operative treatment
Follow-up MRI at 1 yearDiagnostic test
follow-up MRI at 1 year for asymptomatic patients under 35 years of age not wanting to undergo surgery
| Study group | Role | What they receive |
|---|---|---|
| Interval appendectomy | Other | For all patients presenting with a periappendicular abscess, an interval appendectomy is planned at 2 to 3 months after initial conservative treatment, which is considered mandatory for all patients over 35 years of age. If a patient is under 35 and asymptomatic and does not want to undergo surgery, a follow-up MRI at 1 year will be performed. Receives: Procedure: Interval appendectomy |
| Follow-up MRI | Other | For all patients presenting with a periappendicular abscess, an interval appendectomy is planned at 2 to 3 months after initial conservative treatment, which is considered mandatory for all patients over 35 years of age. If a patient is under 35 and asymptomatic and does not want to undergo surgery, a follow-up MRI at 1 year will be performed. Receives: Diagnostic Test: Follow-up MRI at 1 year |
What is being measured
The primary outcome is the main question the study is designed to answer.
The Prevalence of Appendiceal Tumours in Periappendicular Abscess
The Prevalence of Appendiceal Tumours in Patients Presenting With a Periappendicular Abscess - A Nationwide Prospective Cohort Study
Measured: 2-3 months (interval appendectomy)
Secondary outcomes (19)
Tympanic temperature
All patients
Measured: Day 0 (on primary admission)
Imaging (primary diagnosis) finding
All patients
Measured: Day 0 (on primary admission)
Duration of symptoms on admission
All patients
Measured: Day 0 (on primary admission)
Laboratory value: CRP
CRP
Measured: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: leuckocytes
leuk
Measured: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: neutrophils
neutr
Measured: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: hemoglobin
Hb
Measured: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: kreatinine
Krea
Measured: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: CEA
CEA
Measured: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital) and up to 1 year, if no interval appendectomy
Laboratory value. Cg-A
Cg-A
Measured: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)and up to 1 year, if no interval appendectomy
Primary nonoperative treatment
All patients, treatment details
Measured: Day 0 and up to one week
Colonoscopy: endoscopic findings and histology
In both intervention groups
Measured: 2 weeks to 2 months prior to planned interval appendectomy
Interval appendectomy specimen histology
Interval appendectomy patients
Measured: At 3 months
Complications after interval appendectomy
Clavien-Dindo classification, interval appendectomy group
Measured: at the time of surgery
Duration of hospital stay
All patients both at primary treatment, interval appendectomy and follow-up
Measured: up to 2 years
Follow-up MRI findings
In case the patient does not under interval appendectomy
Measured: at 1 year
follow-up CEA
Follow-up MRI patients
Measured: at 1 year
follow-up CgA
Follow-up MRI patients
Measured: at 1 year
Surgery after follow-up MRI
Follow-up with MRI patients
Measured: up to 10 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Nov 2020
- Study start1 Dec 2020 (estimated)
- Primary completion31 Dec 2022 (estimated)
- Study completion31 Dec 2035 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Appendix AbscessStudies of the same condition, open and under way.
- More trials run by Turku University HospitalThe sponsor's other registered studies.
- 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
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- Prospective clinical cohort study
- Masking
- None (open label)
- Enrolment
- 400 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Turku University Hospital
- Sponsor type
- Other government
- Collaborators
- Oulu University Hospital, Tampere University Hospital, Kuopio University Hospital, Jyväskylä Central Hospital, Mikkeli Central Hospital, Lapland Central Hospital, Vaasa Central Hospital, Vaasa, Finland, Seinajoki Central Hospital, North Karelia Central Hospital, South Carelia Central Hospital, Päijänne Tavastia Central Hospital, Satakunta Central Hospital
- Responsible party
- Principal investigator, Paulina Salminen, Turku University Hospital
- Investigators
- Paulina Salminen, prof, MD, Principal investigator, Turku University Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04634448
- Sponsor's protocol ID
- PeriAPPAC-T
- Acronym
- PeriAPPAC-T
- Status last verified
- Nov 2020
- First submitted
- 9 Nov 2020
- Last updated
- 18 Nov 2020
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: IPD is available from the PI upon request, if needed.
Publications
Salminen R, Alajaaski J, Rautio T, Hurme S, Nordstrom P, Makarainen E, Lietzen E, Pinta T, Gronroos-Korhonen M, Rantanen T, Andersen J, Mattila A, Kossi J, Riikola A, Paajanen H, Matikainen M, Pokela V, Salminen P. Appendiceal Tumor Prevalence in Patients With Periappendicular Abscess. JAMA Surg. 2025 May 1;160(5):526-534. doi: 10.1001/jamasurg.2025.0312.
PubMed 40172884
Study at a glance
From the registry record, last updated by the sponsor on 18 Nov 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Prevalence of Appendiceal Tumours in Patients Presenting With a Periappendicular Abscess - A Nationwide Prospective Cohort Study
- ClinicalTrials.gov ID
- NCT04634448
- Acronym / sponsor ID
- PeriAPPAC-T / PeriAPPAC-T
- Conditions
- Appendix Abscess, Appendicitis, Appendix Mass, Appendix Cancer, Appendix Nec, Appendix Tumor
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 400 participants (estimated)
- Lead sponsor
- Turku University HospitalOther government
- Collaborators
- Oulu University Hospital, Tampere University Hospital, Kuopio University Hospital, Jyväskylä Central Hospital, Mikkeli Central Hospital, Lapland Central Hospital, Vaasa Central Hospital, Vaasa, Finland, Seinajoki Central Hospital, North Karelia Central Hospital, South Carelia Central Hospital, Päijänne Tavastia Central Hospital, Satakunta Central Hospital
- Study start
- 1 Dec 2020 (estimated)
- Primary completion
- 31 Dec 2022 (estimated)
- Study completion
- 31 Dec 2035 (estimated)
- First posted
- 18 Nov 2020 (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.
Complicated and uncomplicated appendicitis follow different epidemiological trends also suggesting different pathophysiology behind these two different forms of appendicitis. In 3-10% of patients complicated acute appendicitis is enclosed by formation of a circumscribed periappendicular abscess. The clinically established practice of antibiotic therapy and drainage, if necessary, has been shown safe and effective, allowing the acute inflammatory process to subside in more than 90% of cases without surgery. The need of subsequent interval appendectomy has been questioned with appendicitis recurrence risk varying between 5-26%.
During trial enrollment in our randomized Peri-APPAC trial based on the interim analysis results with 17% appendiceal tumor rate in the study population, the trial was prematurely terminated based on ethical concerns. All the follow-up group patients were re-evaluated and surgery was offered and recommended to all follow-up group patients. After this assessment and additional appendectomies, two more tumors were diagnosed resulting in neoplasm rate of 20% in the whole study group all diagnosed in patients over 40 years and the neoplasm rate in patients over 40 years was 29%.
Based on high appendiceal tumor rate in patients over 40 years, the appendiceal neoplasm rate needs to be further evaluated in prospective patient cohorts undergoing interval appendectomy as interval appendectomy is generally well tolerated and obliterates the risk of missing a possible tumor. In a recent systematic review of retrospective cohort studies with 13.244 acute appendicitis patients the overall appendiceal tumor rate was 1% after appendectomy, but in patients presenting with appendiceal inflammatory mass the neoplasm rate varied from 10% to 29%.
This nationwide prospective multicenter cohort study is designed to assess the prevalence of appendiceal tumors associated with a periappendicular abscess. All consecutive patients presenting with a periappendicular abscess are recommended to undergo interval appendectomy after initial conservative treatment with antibiotic therapy and drainage, if necessary. All patients older than 35 years will undergo laparoscopic interval appendectomy at 2 to 3 months and this is also recommended for the patients between 18 and 35 years of age. Asymptomatic patients under 35 years not willing to undergo interval appendectomy, will undergo a follow-up MRI at 1 year after the initial non-operative treatment.
Detailed description
Complicated and uncomplicated appendicitis follow different epidemiological trends also suggesting different pathophysiology behind these two different forms of appendicitis. In 3-10% of patients complicated acute appendicitis is enclosed by formation of a circumscribed periappendicular abscess. The clinically established practice of antibiotic therapy and drainage, if necessary, has been shown safe and effective, allowing the acute inflammatory process to subside in more than 90% of cases without surgery. The need of subsequent interval appendectomy has been questioned with appendicitis recurrence risk varying between 5-26%.
During trial enrollment in our randomized Peri-APPAC trial, the high incidence of appendiceal tumors in the study population alarmed the researchers. Based on the interim analysis results with 17% appendiceal tumor rate in the study population, the trial was prematurely terminated based on ethical concerns. All the follow-up group patients were re-evaluated and surgery was offered and recommended to all follow-up group patients. After this assessment and additional appendectomies, two more tumors were diagnosed resulting in neoplasm rate of 20% in the whole study group all diagnosed in patients over 40 years and the neoplasm rate in patients over 40 years was 29%.
Based on high appendiceal tumor rate in patients over 40 years, the appendiceal neoplasm rate needs to be further evaluated in prospective patient cohorts undergoing interval appendectomy as interval appendectomy is generally well tolerated and obliterates the risk of missing a possible tumor. In a recent systematic review of retrospective cohort studies with 13.244 acute appendicitis patients the overall appendiceal tumor rate was 1% after appendectomy, but in patients presenting with appendiceal inflammatory mass the neoplasm rate varied from 10% to 29%.
This nationwide prospective multicenter cohort study is designed to assess the prevalence of appendiceal tumors associated with a periappendicular abscess. All of the study hospitals will have a common clinical protocol of recommending interval appendectomy to all patients presenting with a periappendicular abscess after initial conservative treatment with antibiotic therapy and drainage, if necessary. Considering the high rate of appendiceal neoplasms, all patients older than 35 years will undergo laparoscopic interval appendectomy at 2 to 3 months after the successful initial non-operative treatment and this is also recommended for the patients between 18 and 35 years of age. Asymptomatic patients under 35 years not willing to undergo interval appendectomy, will undergo a follow-up MRI at 1 year after the initial non-operative treatment.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Prospective clinical cohort study
| Arm | Type | Receives |
|---|---|---|
| Interval appendectomy | Other | Procedure: Interval appendectomyFor all patients presenting with a periappendicular abscess, an interval appendectomy is planned at 2 to 3 months after initial conservative treatment, which is considered mandatory for all patients over 35 years of age. If a patient is under 35 and asymptomatic and does not want to undergo surgery, a follow-up MRI at 1 year will be performed. |
| Follow-up MRI | Other | Diagnostic Test: Follow-up MRI at 1 yearFor all patients presenting with a periappendicular abscess, an interval appendectomy is planned at 2 to 3 months after initial conservative treatment, which is considered mandatory for all patients over 35 years of age. If a patient is under 35 and asymptomatic and does not want to undergo surgery, a follow-up MRI at 1 year will be performed. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- periappendiceal abscess proven by CT, Mri or US
Key exclusion criteria (1 listed)
- patient declines to participate, complicated appendicitis without periappendiceal abscess
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 |
|---|---|---|
| Interval appendectomyinterval appendectomy at 2 to 3 months after the initial non-operative treatment | Procedure or surgery | Interval appendectomy |
| Follow-up MRI at 1 yearfollow-up MRI at 1 year for asymptomatic patients under 35 years of age not wanting to undergo surgery | Diagnostic test | Follow-up MRI |
Primary outcome
The Prevalence of Appendiceal Tumours in Periappendicular Abscess
Time frame: 2-3 months (interval appendectomy)
The Prevalence of Appendiceal Tumours in Patients Presenting With a Periappendicular Abscess - A Nationwide Prospective Cohort Study
19 secondary outcomes
Tympanic temperature
Time frame: Day 0 (on primary admission)
Imaging (primary diagnosis) finding
Time frame: Day 0 (on primary admission)
Duration of symptoms on admission
Time frame: Day 0 (on primary admission)
Laboratory value: CRP
Time frame: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: leuckocytes
Time frame: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: neutrophils
Time frame: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: hemoglobin
Time frame: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: kreatinine
Time frame: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)
Laboratory value: CEA
Time frame: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital) and up to 1 year, if no interval appendectomy
Laboratory value. Cg-A
Time frame: Day 0 (on primary admission) up to 3-5 days (discharge from the hospital)and up to 1 year, if no interval appendectomy
Primary nonoperative treatment
Time frame: Day 0 and up to one week
Colonoscopy: endoscopic findings and histology
Time frame: 2 weeks to 2 months prior to planned interval appendectomy
Interval appendectomy specimen histology
Time frame: At 3 months
Complications after interval appendectomy
Time frame: at the time of surgery
Duration of hospital stay
Time frame: up to 2 years
Follow-up MRI findings
Time frame: at 1 year
follow-up CEA
Time frame: at 1 year
follow-up CgA
Time frame: at 1 year
Surgery after follow-up MRI
Time frame: up to 10 years
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 18 Nov 2020.
- Derived from this study: PubMed 40172884Salminen R, Alajaaski J, Rautio T, Hurme S, Nordstrom P, Makarainen E, Lietzen E, Pinta T, Gronroos-Korhonen M, Rantanen T, Andersen J, Mattila A, Kossi J, Riikola A, Paajanen H, Matikainen M, Pokela V, Salminen P. Appendiceal Tumor Prevalence in Patients With Periappendicular Abscess. JAMA Surg. 2025 May 1;160(5):526-534. doi: 10.1001/jamasurg.2025.0312.
- Individual participant dataSharing planned: Yes. IPD is available from the PI upon request, if needed.
Related trials for Appendix Abscess
Not yet recruitingObservational study
Study of Management of Appendicular Abscess
Appendiceal Abscess
Not yet recruitingObservational study
Peri-appendiceal Abscess and Phlegmon in Acute Complicated Appendicitis Patients
Acute Complicated Appendicitis With Peri-appendiceal Abscess or Phlegmon
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.
Jenny Alajääski, MD contact
Paulina Salminen, prof, MD principal investigator
Turku University Hospital
Questions about this trial
What is this clinical trial studying?
A study testing Interval appendectomy and Follow-up MRI at 1 year in people with Appendix Abscess and Appendicitis, run by Turku University Hospital.
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 1 inclusion and 1 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 18 Nov 2020. 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 Paulina Salminen, prof, MD (+35823130000, paulina.salminen@tyks.fi), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The Prevalence of Appendiceal Tumours in Periappendicular Abscess (time frame: 2-3 months (interval appendectomy)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04634448, which also lists 1 linked publication.
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 18 Nov 2020.