Sentinel Node Biopsy in Breast Cancer: Omission of Axillary Clearance After Macrometastases. A Randomized Trial.

July 12, 2026 updated by: Jana de Boniface, Karolinska Institutet

Survival and Axillary Recurrence Following Sentinel Node-positive Breast Cancer Without Completion Axillary Lymph Node Dissection - a Randomized Study of Patients With Macrometastases in the Sentinel Node

Since the introduction of sentinel node biopsy in breast cancer, it has become clear that its use is reliable and reproducible. Today, it is clinical routine to not remove further lymph nodes from the axilla (arm pit) in case the sentinel node (which is the first lymph node/s reached by lymphatic flow from the breast) is free of tumor deposits. It is also routine to leave remaining lymph nodes behind in case the sentinel node contains a minimal cluster of tumor cells, called isolated tumor cells (formerly submicrometastasis). Even in slightly larger tumor deposits, so called micrometastasis (up to 2 mm in size), it has been shown that a completion axillary clearance (removal of further lymph nodes from the arm pit) does not contribute to a better survival. Data from a randomized study indicate that it seems safe to omit axillary clearance even if the sentinel node biopsy shows up to 2 nodes with tumor deposits over 2 mm in size (macrometastasis). These studies have changed clinical practice in many countries, however, it is still debated whether it is safe to omit axillary clearance in the case of sentinel node macrometastasis due to under-recruitment in the aforementioned study. The rationale for omitting extensive axillary surgery is the avoidance of postoperative morbidity such as arm lymphedema, loss of sensation, pain and swelling.

The hypothesis is that refraining from axillary clearance in breast cancer patients with 1-2 sentinel nodes with macrometastasis will not worsen 5-year overall survival (primary endpoint) by more than a maximum of 2.5%.

This study is a prospective international randomized trial planning for enrolment of 3500 patients.

Breast cancer patients without signs of axillary nodal involvement will be eligible for sentinel node biopsy. Those who are found to have up to two sentinel node containing macrometastasis will be informed about this trial Those wishing to participate will be randomized to either undergo further axillary surgery (clearance) or not. Secondary endpoints are oncological outcomes at 1-5, 10 and 15 years (local, regional and distant recurrence, recurrence-free and breast cancer-specific survival and contralateral breast cancer), patient-reported arm morbidity at 1, 3, 5 and 10 years, patient-reported quality of life at 1, 3, 5, and 10 years, and health economic outcomes at 1, 3, 5 and 10 years.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Details can be found on www.senomac.se

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
2766

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Denmark
      • Aabenraa, Denmark
        • Sygehus Sonderjylland
      • Aalborg, Denmark
        • Aalborg University Hospital
      • Aarhus, Denmark
        • Aarhus University Hospital
      • Copenhagen, Denmark
        • Rigshospitalet
      • Esbjerg, Denmark
        • Sydvestjysk Sygehus
      • Lillebaelt, Denmark
        • Sygehus Lillebaelt
      • Odense, Denmark
        • Odense University Hospital
      • Randers, Denmark
        • Randers Regionshospitalet
      • Viborg, Denmark
        • Regionshospitalet Viborg
  • Greece
      • Athens, Greece
        • Athens University Hospital
  • Sweden
      • Gothenburg, Sweden
        • Sahlgrenska University Hospital
      • Gävle, Sweden
        • Gavle Sjukhus
      • Halmstad, Sweden
        • Hallands sjukhus
      • Helsingborg, Sweden
        • Helsingborg lasarett
      • Jönköping, Sweden
        • Länssjukhuset Ryhov
      • Kalmar, Sweden
        • Kalmar sjukhus
      • Karlskrona, Sweden
        • Blekinge sjukhuset
      • Karlstad, Sweden
        • Karlstad sjukhus
      • Kristianstad, Sweden
        • Central Hospital Kristianstad
      • Linköping, Sweden
        • Linköping University Hospital
      • Lund, Sweden
        • Malmö/Lund University Hospital
      • Skövde/Lidköping, Sweden
        • Skaraborgs Sjukhus
      • Stockholm, Sweden
        • Karolinska University Hospital
      • Stockholm, Sweden
        • Southern Gerenal Hospital
      • Stockholm, Sweden
        • St. Görans Hospital
      • Sundsvall, Sweden
        • Sundsvall länssjukhus
      • Uddevalla, Sweden
        • Uddevalla Sjukhus
      • Umeå, Sweden
        • Umeå University Hospital
      • Uppsala, Sweden
        • Akademiska sjukhuset
      • Varberg, Sweden
        • Varbergs sjukhus
      • Västervik, Sweden
        • Västervik Hospital
      • Västerås, Sweden
        • Västerås Central Hospital
      • Örebro, Sweden
        • Örebro University Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

14 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Patients with invasive breast cancer (T1-T3)
  • N0 on palpation
  • Preoperative ultrasound performed
  • Macrometastasis in 1-2 sentinel lymph nodes
  • The patient must have provided oral and written consent
  • Age ≥ 18 years

Exclusion Criteria:

  • Metastases outside of the ipsilateral axilla
  • Prior history of invasive breast cancer
  • Pregnancy
  • Bilateral breast cancer if one side meets exclusion criteria
  • Medical contraindication for radiotherapy or systemic treatment
  • Inability to absorb or understand the meaning of the study information; for example, through disability, inadequate language skills or dementia.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
No Intervention: Axillary clearance
Patients in this arm will be treated by completion axillary clearance after a sentinel node biopsy showing 1-2 nodes with macrometastasis
Experimental: No axillary clearance
Patients in this arm will not undergo further axillary surgery after a sentinel node biopsy showing 1-2 nodes with macrometastasis
Procedure: Omission of axillary clearance
The intervention is the omission of completion axillary clearance after the detection of sentinel node macrometastasis

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
overall survival
Time Frame: up to 15 years
death of any cause in both arms measured at a median follow-up of 5
up to 15 years

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
recurrence-free survival
Time Frame: 5, 10 and 15 years
Any invasive breast cancer recurrence and death of any cause are regarded as events
5, 10 and 15 years
breast cancer-specific survival
Time Frame: 5, 10 and 15 years
Death attributed to breast cancer is regarded as the event
5, 10 and 15 years
patient-reported outcomes
Time Frame: early postoperative, 1, 3, 5, and 10 years
Patients report on any arm-related problems and functional outcomes at an early postoperative assessment and after 1, 3, 5 and 10 years. Questionnaires include EORTC QLQ-BR23 and C30 and Lymph-ICF.
early postoperative, 1, 3, 5, and 10 years
health economy
Time Frame: 1, 3, 5 and 10 years
The use of health care resources is assessed by QUALYs by means of the EQ5D questionnaire
1, 3, 5 and 10 years
additional oncological outcomes
Time Frame: yearly 1-5 years, 10 and 15 years
local, regional and distant recurrences will be reported as events and reported within recurrence-free survival and as distinct events
yearly 1-5 years, 10 and 15 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Karolinska Institutet

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
The Swedish Research Council
Swedish Cancer Foundation
Nordic Cancer Union

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Jana de Boniface, PhD, Karolinska Institutet
  • Study Chair: Jan Frisell, Professor, Karolinska University Hospital
  • Study Chair: Leif Bergkvist, Professor, Central Hospital Västerås
  • Study Chair: Yvette Andersson, PhD, Central Hospital Västerås
  • Study Chair: Lisa Ryden, Professor, Lund University
  • Study Chair: Johan Ahlgren, PhD, Region Örebro County
  • Study Chair: Tove Tvedskov Filtenborg, MD, Rigshospitalet Copenhagen, Dnmark
  • Study Chair: Michalis Kontos, PhD, University of Athens
  • Study Chair: Birgitte Offersen, Professor, University of Aarhus
  • Principal Investigator: Thorsten Kühn, Professor, Klinikum Esslingen
  • Principal Investigator: Toralf Reimer, Professor, Universität Rostock
  • Principal Investigator: Oreste Gentilini, San Raffaele Hospital, Milano
  • Principal Investigator: Roland Reitsamer, Universitätsklinikum Salzburg
  • Study Chair: Olofsson Roger, PhD, Sahlgrenska University Hospital
  • Study Chair: Dan Lundstedt, PhD, Sahlgrenska University Hospital
  • Study Chair: Malin Sund, Professor, University Hospital, Umeå
  • Principal Investigator: Peer Christiansen, Professor, Aarhus University Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 27, 2015

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 31, 2021

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 31, 2031

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
September 11, 2014

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 12, 2014

First Posted (Estimated)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 15, 2014

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
July 14, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 12, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • SENOMAC

Plan for Individual participant data (IPD)

Study Data/Documents

  1. Study Protocol
    Information comments: Study protocol and patient information (English)

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings