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Breast CancerNCT04303715

No Axillary sUrgical Treatment In Clinically Lymph Node Negative Patients After UltraSonography

A study testing No SLNB and SLNB in people with Breast Cancer and Sentinel Lymph Node, run by Seoul National University Hospital at 1 site in South Korea.

Active, not recruiting

Under way, not looking for participants. Everyone needed has enrolled. The study is still running.

Official record
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Trial summary

NAUTILUS study is a prospective, multicenter, RCT. Clinically T1,T2, node negative BCS candidates with no evidence of metastases in AUS are 1:1 randomized into no SLNB group and SLNB group. Read more about this study

Who is it for?
Ages 19 years and older, women only
Conditions the study is for
Breast Cancer, Sentinel Lymph Node
What is being tested?
No SLNB and SLNB
Type of treatment
Surgery or procedure
Could I receive a placebo?
No, everyone receives an active treatment
How many people
1,734 participants
Where
1 siteSouth Korea
Study dates
15 Sep 2020to 31 Dec 2027
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 19 years and older
  • Women only
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Women ≥ 19 years
  • Invasive unilateral breast carcinoma with histological confirmation
  • History of invasive breast cancer
  • Histologically or radiologically no suspicion of distant metastases
  • Performance status corresponding to ECOG grade 0-2
  • Tumor size clinically and radiologically ≤ 5cm, independent of hormone receptor and HER2 status
Show all 10Show fewer
  • Clinically and sonographically negative axillary lymph nodes before biopsy; core needle biopsy or fine needle aspiration of suspicious lymph node required
  • BCS candidate with postoperative whole-breast irradiation and adequate systemic therapy
  • No psychological and geographical restriction in follow-up
  • Written informed consent

Who cannot join

  • History of any cancer in the previous 5 years
  • Bilateral breast cancer
  • Invasive breast cancer treated with neoadjuvant therapy
  • Tumor size clinically and radiologically > 5cm
  • Mastectomy candidate
  • Pregnancy and breastfeeding
  • Male breast cancer
  • Unable to understand and fill out questionnaires

Trial locations and contacts

1 site in 1 country.

South Korea1 site

  • Seoul National University Hospital

    Seoul, Seoul, 03080

Other trials in South Korea

About this study

Official title: No Axillary sUrgical Treatment In Clinically Lymph Node Negative Patients After UltraSonography[NAUTILUS]: A Prospective, Multicenter, Phase III Clinical Trial

NAUTILUS study is a prospective, multicenter, RCT. Clinically T1,T2, node negative BCS candidates with no evidence of metastases in AUS are 1:1 randomized into no SLNB group and SLNB group.

NAUTILUS study aim to establish the minimally invasive treatment of breast cancer by reexamining the necessity of sentinel lymph node biopsy among patients with invasive breast cancer who have tumors under 5cm, are clinically node-negative, and are having breast conserving surgery performed.

Read the detailed description

[Background] Skipping ALND, the follow-up treatment in SN-positive patients, has non-inferior oncological outcomes compared to SLNB-only group, given that there is no severe SN metastases.

Axillary ultrasound can effectively exclude high nodal burden, showing 95% NPV in a systematic review.

SLNB has morbidity including lymphedema, limited range of motion, pain, and other post-surgical complications, eventually leading to reduced quality of life.

Considering improvement of imaging modalities and adjuvant care, survival outcome of SLNB must be re-evaluated. Especially research reflective of the regional specificities of Korea and Asia-Pacific is needed.

[Study design] Prospective, Multicenter, RCT.

[Statistical considerations] According to Z0011 trial, 5yr DFS in eligible patients is expected to be 86%, which is between previous data of 88.6% in cT1,2 and SN-negative patients4, and 83.9% in cT1,2 and 1-2 SN-positive patients.

Non-inferiority margin is set at 5%. With 5% significance level and 80% power, 780 patients are needed in each group. Assuming a 10% drop out rate, 1734 patients need to be recruited.

[Screening and Randomization] Participants undergo screening tests that assess eligibility according to inclusion/exclusion criteria.

In order to identify axillary lymph node metastases, axillary ultrasound is first performed by radiologists. Patients showing normal features are enrolled, while for conditionally normal patients, with only 1 suspicion of low nodal burden, axillary lymph node biopsy should be performed. Suspicious patients are excluded under following conditions: patients with 1 or more suspicion of high nodal burden, 2 or more suspicion of low nodal burden, or T2 invasive lobular carcinoma patients with 1 or more low nodal burden. The severity of nodal burden is defined through the criteria.

Patients who underwent radiological axillary staging are randomly assigned (1:1) to the study arm and the control arm before surgical care. Stratification is done based on trial centers and tumor sizes.

[Post-surgical care] All patients are planned to receive ipsilateral whole breast radiation. Patients randomized to non-SLNB arm are recommended to follow high tangential radiotherapy protocol, in which upper margin of radiation field includes axillary level I and II or lies within 2CM from humeral head.

Additional treatment may be performed if deemed necessary by the researcher

[Objectives]

  1. Primary objective
  • 5yr Disease Free Survival
  1. Secondary objectives
  • 5yr Overall Survival
  • 5yr Distant Metastasis Free Survival
  • Axillary recurrence rate
  • Patient reported AE
  • QoL
Being tested
No SLNB, SLNB
Medical subject headings
Breast Neoplasms

What participants receive

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

  • No SLNBProcedure or surgery

    BCS only. Ommission of SLNB by axilla ultrasonography among selective breast cancer patients

  • SLNBProcedure or surgery

    BCS with SLNB(+/-ALND)

Study groups in NCT04303715
Study groupRoleWhat they receive
No SLNB groupExperimentalThe study arm - BCS without SLNB
Receives: Procedure: No SLNB
SLNB groupOtherThe Control Arm - BCS with SLNB(+/-ALND)
Receives: Procedure: SLNB

What is being measured

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

  1. Disease Free Survival (DFS)

    Evaluate disease free survivals

    Measured: 5 years

Secondary outcomes (6)

  1. Overall Survival (OS)

    Evaluate overall survival

    Measured: 5 years

  2. Distant Metastasis Free Survival (DMFS)

    Evaluate distant metastasis free survival

    Measured: 5 years

  3. Axillary recurrence rate

    Evaluate ipsilateral axillary recurrence rate

    Measured: 5 years

  4. Locoregional Recurrence Rate (LRR)

    Evaluate locoregional recurrence rate

    Measured: 5 years

  5. Patient reported Adverse Events (AEs)

    Evaluate Patient reported Adverse Events

    Measured: 1 year

  6. QoL

    Evaluate Quality of Life of patient by EORTC QLQ-C30 questionnaire

    Measured: 1 year

Timeline

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

  1. First posted11 Mar 2020
  2. Study start15 Sep 2020
  3. Primary completion31 Dec 2027 (estimated)
  4. Study completion31 Dec 2027 (estimated)

Resources

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
None (open label)
Enrolment
1,734 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04303715
Sponsor's protocol ID
NAUTILUS study
Status last verified
Sep 2025
First submitted
8 Mar 2020
Last updated
13 Feb 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • Ryu JM, Lee HB, Han W, Chung IY, Ahn SH, Lee S, Park S, Jeong J, Lim W, Lee JE, Kang E, Chang JH, Shin KH, Chang JM, Moon WK, Kim EK; NAUTILUS Investigators. Clinicopathologic characteristics and lymph node status in the NAUTILUS clinical trial:KBCSG-21. Eur J Surg Oncol. 2026 Apr;52(4):111458. doi: 10.1016/j.ejso.2026.111458. Epub 2026 Feb 2.

    PubMed 41689946

  • Jung JG, Ahn SH, Lee S, Kim EK, Ryu JM, Park S, Lim W, Jung YS, Chung IY, Jeong J, Chang JH, Shin KH, Chang JM, Moon WK, Han W. No axillary surgical treatment for lymph node-negative patients after ultra-sonography [NAUTILUS]: protocol of a prospective randomized clinical trial. BMC Cancer. 2022 Feb 20;22(1):189. doi: 10.1186/s12885-022-09273-1.

    PubMed 35184724

  • Chang JM, Shin HJ, Choi JS, Shin SU, Choi BH, Kim MJ, Yoon JH, Chung J, Kim TH, Han BK, Kim HH, Moon WK. Imaging Protocol and Criteria for Evaluation of Axillary Lymph Nodes in the NAUTILUS Trial. J Breast Cancer. 2021 Dec;24(6):554-560. doi: 10.4048/jbc.2021.24.e47. Epub 2021 Nov 24.

    PubMed 34877830

Questions about this trial

What is this clinical trial studying?

A study testing No SLNB and SLNB in people with Breast Cancer and Sentinel Lymph Node, run by Seoul National University Hospital at 1 site in South Korea.

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 10 inclusion and 8 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: under way, not looking for participants, as of the sponsor's last update on 13 Feb 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 South Korea. 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?

Disease Free Survival (DFS) (time frame: 5 years). 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 NCT04303715, which also lists 3 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 13 Feb 2026.

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