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HemorrhoidPROCTO-CLUSTERNCT07427927

Data-driven Clustering in Hemorrhoid Surgery: Retrospective Monocentric Study for the Identification of Clinical Phenotypes

An observational study of Hemorrhoid and Hemorrhoid Prolapse, run by IRCCS Policlinico S. Donato at 1 site in Italy.

Enrolling by invitation

Enrolling by invitation. The study team selects and invites participants, usually from an existing group of patients.

Sites and contacts
Official record
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Trial summary

This retrospective, single-center observational study will use routinely collected perioperative data from adults undergoing surgery for symptomatic hemorrhoidal disease to identify data-driven clinical phenotypes. Read more about this study

Who is it for?
Ages 18 years and older
Conditions the study is for
Hemorrhoid, Hemorrhoid Prolapse
What is being tested?
Any surgical procedure for hemorrhoidal disease
Type of treatment
Surgery or procedure
How many people
100 participants
Where
1 siteItaly
Study dates
1 Dec 2024to Dec 2026
Phase
Observational
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
  • No healthy volunteers
  • Adult, Older adult

Study population: Patients undergoing surgery for symptomatic hemorrhoidal disease

Who may be able to join

  • Age ≥ 18 years
  • Clinical and/or intraoperative diagnosis of symptomatic hemorrhoidal disease
  • Availability of complete perioperative data: demographic, clinical, surgical, and postoperative variables Exclusion criteria
  • Incomplete or missing clinical data
  • Presence of anorectal neoplastic conditions (e.g., anal or rectal carcinoma)
  • Anorectal surgery within the previous 6 months (to avoid confounding effects on symptoms and anatomy)

Who cannot join

None listed.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Italy1 site
  • IRCCS Policlinico San Donato

    San Donato Milanese, Milan, 20097

Other trials in Italy

About this study

This retrospective, single-center observational study will use routinely collected perioperative data from adults undergoing surgery for symptomatic hemorrhoidal disease to identify data-driven clinical phenotypes. Unsupervised machine learning will be applied to characterize clusters of patients based on demographic, clinical, anatomical, and surgical variables. The study will explore whether the resulting phenotypes differ in operative complexity and postoperative course, and will generate hypotheses to inform future predictive models and personalized surgical planning.

Read the detailed description

Hemorrhoidal disease presents with heterogeneous symptom patterns, anatomical findings, and operative strategies that are not fully captured by traditional degree-based classifications. This study aims to identify latent, clinically interpretable phenotypes among surgical patients using a fully unsupervised machine learning pipeline applied to routinely collected perioperative data from a high-volume tertiary referral center.

This is a retrospective, observational analysis of de-identified institutional records. The analytic dataset will include routinely documented variables spanning baseline demographics/anthropometrics, symptom profile and relevant clinical history, operative technique and intraoperative descriptors, and routinely captured postoperative follow-up information. Data will be extracted using a predefined data dictionary and standardized preprocessing rules to support reproducibility and reduce variability in variable definitions.

The primary analytic approach will be unsupervised clustering. Variables will be cleaned and standardized prior to modeling. Dimensionality reduction will be performed using t-distributed stochastic neighbor embedding (t-SNE), initialized with principal component analysis to improve stability. Cluster discovery will then be conducted using k-means clustering on the reduced feature space. A range of cluster solutions will be explored, and the final solution will be selected using internal validity metrics (e.g., silhouette-based measures) together with assessment of clinical interpretability. Model robustness will be evaluated through repeated runs across multiple random seeds and key parameter settings to assess stability of cluster assignments.

After cluster assignment, clusters will be characterized using descriptive and comparative statistics to identify variables that most differentiate phenotypes. Post-hoc feature relevance/importance approaches will be used to explore which demographic, clinical, and surgical factors most strongly contribute to cluster formation, with emphasis on effect sizes and clinically meaningful patterns rather than hypothesis-testing alone. Findings will be used to generate hypotheses regarding phenotypes that may be associated with greater operative complexity and different postoperative trajectories, supporting future work on predictive modeling and individualized surgical decision support.

All analyses will be conducted within a controlled institutional environment using validated statistical and data-mining software, with documented parameter settings and version tracking to enable reproducibility. Only de-identified data will be used for analysis, and results will be reported in aggregate to protect patient privacy.

Being tested
Any surgical procedure for hemorrhoidal disease
Keywords
Hemorrhoidal Disease, Unsupervised Machine Learning
Medical subject headings
Hemorrhoids

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Any surgical procedure for hemorrhoidal diseaseProcedure or surgery

    standard hemorrhoidectomy, advanced hemorrhoidectomy, prolapsectomy, Doppler-guided procedures, or combined techniques

Study groups in NCT07427927
Study groupRoleWhat they receive
patients who underwent surgery for symptomatic hemorrhoidal diseaseConsecutive patients who underwent surgery for symptomatic hemorrhoidal disease at IRCCS Policlinico San Donato between December 2024 and June 2025. Consecutive enrollment was chosen to minimize selection bias and to represent the full spectrum of disease severity in the surgical setting. Inclusion criteria Age ≥ 18 years Clinical and/or intraoperative diagnosis of symptomatic hemorrhoidal disease Availability of complete perioperative data: demographic, clinical, surgical, and postoperative variables Exclusion criteria Incomplete or missing clinical data Presence of anorectal neoplastic conditions (e.g., anal or rectal carcinoma) Anorectal surgery within the previous 6 months (to avoid confounding effects on symptoms and anatomy)
Receives: Procedure: Any surgical procedure for hemorrhoidal disease

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Internal validity of the unsupervised clustering solution (silhouette coefficient)

    Silhouette coefficient of the final k-means clustering solution derived from t-SNE-reduced perioperative data. The silhouette coefficient will be used as the primary internal validity metric to quantify cluster cohesion and separation for the selected number of clusters.

    Measured: From completion of dataset extraction/cleaning through completion of clustering analysis (retrospective analysis of surgeries performed December 2024 to June 2025)

Secondary outcomes (6)
  1. Cluster stability and reproducibility across model runs

    Stability of cluster assignments across multiple random seeds and t-SNE parameter settings (including perplexity), summarized by reproducibility/consistency of membership and stability of internal validity metrics across runs.

    Measured: From completion of dataset extraction/cleaning through completion of clustering robustness analyses (retrospective analysis of surgeries performed December 2024 to June 2025)

  2. Operative duration (proxy of operative complexity)

    Operative duration (minutes) recorded in the operative report/perioperative database; compared across identified phenotypes.

    Measured: Intraoperative (day of surgery)

  3. Postoperative pain intensity

    Pain intensity as documented in routine postoperative records/follow-up notes (e.g., numeric rating scale when available or clinician-documented pain status), analyzed as pain trajectory/pattern across early and intermediate follow-up and compared across clusters.

    Measured: From surgery to 6 month postoperatively

  4. Postoperative complications (Clavien-Dindo classification)

    Any postoperative complication recorded in routine follow-up, graded according to the Clavien-Dindo system; complication rates and severity compared across clusters.

    Measured: From surgery to 1 month postoperatively (early complications) and up to 6 months postoperatively (late complications)

  5. Time to return to routine activities

    Time to return to routine activities/work when documented in follow-up notes; compared across phenotypes.

    Measured: From surgery to 1 month postoperatively

  6. Recurrence

    Recurrence patterns or persistence/return of hemorrhoid-related symptoms (e.g., bleeding/prolapse/other symptoms) as documented in routine follow-up and need for re-evaluation or additional intervention; compared across clusters.

    Measured: 1 month and 6 months postoperatively

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted23 Feb 2026
  2. Study start1 Dec 2024
  3. Primary completion31 Dec 2025
  4. Study completionDec 2026 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Observational model
Cohort
Time perspective
Retrospective
Enrolment
100 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07427927
Sponsor's protocol ID
CET 18-2026
Acronym
PROCTO-CLUSTER
Status last verified
Aug 2026
First submitted
5 Feb 2026
Last updated
27 Aug 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Bernabe-Diaz JA, Franco M, Vivo JM, Fernandez-Breis JT. Optimizing clustering-based analytical methods with trimmed and sparse clustering. Comput Biol Med. 2025 Aug;194:110436. doi: 10.1016/j.compbiomed.2025.110436. Epub 2025 Jun 16.

    PubMed 40527163
  • Xiao C, Hong S, Huang W. Optimizing graph layout by t-SNE perplexity estimation. Int J Data Sci Anal. 2023;15(2):159-171. doi:10.1007/s41060-022-00348-7

  • Goldenholz DM, Sun H, Ganglberger W, Westover MB. Sample Size Analysis for Machine Learning Clinical Validation Studies. Biomedicines. 2023 Feb 23;11(3):685. doi: 10.3390/biomedicines11030685.

    PubMed 36979665
  • De Marco S, Tiso D. Lifestyle and Risk Factors in Hemorrhoidal Disease. Front Surg. 2021 Aug 18;8:729166. doi: 10.3389/fsurg.2021.729166. eCollection 2021.

    PubMed 34485376
  • Robinson PN, Mungall CJ, Haendel M. Capturing phenotypes for precision medicine. Cold Spring Harb Mol Case Stud. 2015 Oct;1(1):a000372. doi: 10.1101/mcs.a000372.

    PubMed 27148566
  • Brillantino A, Renzi A, Talento P, Brusciano L, Marano L, Grillo M, Maglio MN, Foroni F, Palumbo A, Sotelo MLS, Vicenzo L, Lanza M, Frezza G, Antropoli M, Gambardella C, Monaco L, Ferrante I, Izzo D, Giordano A, Pinto M, Fantini C, Gasparrini M, Schiano Di Visconte M, Milazzo F, Ferreri G, Braini A, Cocozza U, Pezzatini M, Gianfreda V, Di Leo A, Landolfi V, Favetta U, Agradi S, Marino G, Varriale M, Mongardini M, Pagano CEFA, Contul RB, Gallese N, Ucchino G, D'Ambra M, Rizzato R, Sarzo G, Masci B, Da Pozzo F, Ascanelli S, Liguori P, Pezzolla A, Iacobellis F, Boriani E, Cudazzo E, Babic F, Geremia C, Bussotti A, Cicconi M, Sarno AD, Mongardini FM, Brescia A, Lenisa L, Mistrangelo M, Zuin M, Mozzon M, Chiriatti AP, Bottino V, Ferronetti A, Rispoli C, Carbone L, Calabro G, Tirro A, de Vito D, Ioia G, Lamanna GL, Asciore L, Greco E, Bianchi P, D'Oriano G, Stazi A, Antonacci N, Renzo RMD, Poto GE, Ferulano GP, Longo A, Docimo L. The Italian Unitary Society of Colon-Proctology (Societa Italiana Unitaria di Colonproctologia) guidelines for the management of acute and chronic hemorrhoidal disease. Ann Coloproctol. 2024 Aug;40(4):287-320. doi: 10.3393/ac.2023.00871.0124. Epub 2024 Aug 30.

    PubMed 39228195
  • De Gregorio MA, Guirola JA, Serrano-Casorran C, Urbano J, Gutierrez C, Gregorio A, Sierre S, Ciampi-Dopazo JJ, Bernal R, Gil I, De Blas I, Sanchez-Ballestin M, Millera A. Catheter-directed hemorrhoidal embolization for rectal bleeding due to hemorrhoids (Goligher grade I-III): prospective outcomes from a Spanish emborrhoid registry. Eur Radiol. 2023 Dec;33(12):8754-8763. doi: 10.1007/s00330-023-09923-3. Epub 2023 Jul 17.

    PubMed 37458757
  • van Oostendorp JY, Grossi U, Hoxhaj I, Kimman ML, Kuiper SZ, Breukink SO, Han-Geurts IJM, Gallo G. Limitations of the Goligher classification in randomized trials for hemorrhoidal disease: a qualitative systematic review of selection criteria. Tech Coloproctol. 2025 Jun 10;29(1):133. doi: 10.1007/s10151-025-03170-y.

    PubMed 40493094
  • Dekker L, Han-Geurts IJM, Grossi U, Gallo G, Veldkamp R. Is the Goligher classification a valid tool in clinical practice and research for hemorrhoidal disease? Tech Coloproctol. 2022 May;26(5):387-392. doi: 10.1007/s10151-022-02591-3. Epub 2022 Feb 9.

    PubMed 35141793
  • Bozovic B, Radoicic M, Jankovic S, Andelkovic J, Kostic M. Pharmacoeconomic Aspects of Treating Hemorrhoidal Disease-Cost of Illness Study Based on Data from Balkan Country with Recent History of Social and Economic Transition. Iran J Public Health. 2021 Jun;50(6):1288-1290. doi: 10.18502/ijph.v50i6.6433. No abstract available.

    PubMed 34540753
  • Rorvik HD, Davidsen M, Gierloff MC, Brandstrup B, Olaison G. Quality of life in patients with hemorrhoidal disease. Surg Open Sci. 2023 Feb 24;12:22-28. doi: 10.1016/j.sopen.2023.02.004. eCollection 2023 Mar.

    PubMed 36876020
  • Pata F, Gallo G, Pellino G, Vigorita V, Podda M, Di Saverio S, D'Ambrosio G, Sammarco G. Evolution of Surgical Management of Hemorrhoidal Disease: An Historical Overview. Front Surg. 2021 Aug 30;8:727059. doi: 10.3389/fsurg.2021.727059. eCollection 2021.

    PubMed 34527700
  • Roberts K. What Are Hemorrhoids? JAMA. 2025 Nov 6. doi: 10.1001/jama.2025.17253. Online ahead of print.

    PubMed 41196608
  • Wang L, Ni J, Hou C, Wu D, Sun L, Jiang Q, Cai Z, Fan W. Time to change? Present and prospects of hemorrhoidal classification. Front Med (Lausanne). 2023 Oct 11;10:1252468. doi: 10.3389/fmed.2023.1252468. eCollection 2023.

    PubMed 37901411
  • Al-Masoudi RO, Shosho R, Alquhra D, Alzahrani M, Hemdi M, Alshareef L. Prevalence of Hemorrhoids and the Associated Risk Factors Among the General Adult Population in Makkah, Saudi Arabia. Cureus. 2024 Jan 3;16(1):e51612. doi: 10.7759/cureus.51612. eCollection 2024 Jan.

    PubMed 38318578

Questions about this trial

What is this clinical trial studying?

An observational study of Hemorrhoid and Hemorrhoid Prolapse, run by IRCCS Policlinico S. Donato at 1 site in Italy.

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 6 inclusion and 0 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: enrolling by invitation, as of the sponsor's last update on 27 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Italy. Whether a site is taking part right now should be confirmed with that site. See every site.

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?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Internal validity of the unsupervised clustering solution (silhouette coefficient) (time frame: From completion of dataset extraction/cleaning through completion of clustering analysis (retrospective analysis of surgeries performed December 2024 to June 2025)). 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 NCT07427927, which also lists 16 linked publications.

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 27 Aug 2026.

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