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Carbon Suspension vs. Metallic Marker for Axillary Lymph Node Marking in Breast Cancer After Neoadjuvant Therapy

A Randomized Trial Comparing Carbon Suspension (Black Eye) and Metallic Markers (TWIRL ULTRACOR) for Localization of Metastatic Axillary Lymph Nodes Prior to Neoadjuvant Systemic Therapy in Breast Cancer Patients.

Status
Recruiting
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07106112
Acronym
COMET
Enrollment
110
Registered
2025-08-06
Start date
2025-05-15
Completion date
2026-12-31
Last updated
2025-08-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Cancer

Keywords

Carbon suspension, Axillary lymph node marking, Neoadjuvant therapy, Targeted axillary dissection, Metallic marker

Brief summary

This single-center, randomized study aims to compare the intraoperative detection rates of axillary lymph nodes marked with carbon suspension versus metallic markers in breast cancer patients (T1-3N1M0) before neoadjuvant therapy. Primary endpoint: frequency of marked lymph node identification during surgery. Secondary endpoints: time from marking to surgery and quality of life (EORTC QLQ-BR23).

Detailed description

Interventions: Group 1: Ultrasound-guided injection of 0.5 mL carbon suspension (Black Eye). Group 2: Ultrasound-guided placement of a metallic marker (TWIRL ULTRACOR). Follow-up: 6 months post-surgery. Design: Randomized 1:1, non-inferiority trial.

Interventions

PROCEDUREUltrasound-guided carbon suspension (Black Eye) injection

Under ultrasound guidance, 0.5 mL of sterile carbon particle suspension (Black Eye) is injected into the capsule of the metastatic axillary lymph node(s). Technique: Performed using a high-frequency linear ultrasound probe (e.g., 12 MHz) and a 22G needle. Target: Up to 3 pathologically confirmed metastatic lymph nodes. Timing: Performed before initiation of neoadjuvant systemic therapy (NST). Rationale: Carbon suspension provides long-term visual localization due to its black staining properties. Inert and biocompatible, with minimal risk of allergic reactions. Patients proceed to standard NST based on tumor subtype (chemotherapy, targeted therapy, or endocrine therapy). Post-NST imaging (ultrasound, CT, or PET-CT) to assess treatment response. Surgical Intervention: Targeted axillary dissection (TAD) with removal of marked nodes + sentinel lymph node biopsy (SLNB) using fluorescent dye. Intraoperative frozen section analysis (hematoxylin & eosin staining) of excised nodes.

PROCEDUREUltrasound-guided metallic marker (TWIRL ULTRACOR) placement

A 4-mm nitinol (nickel-titanium alloy) marker (TWIRL ULTRACOR) is deployed into the metastatic lymph node(s) under ultrasound guidance. Technique: Uses a specialized introducer kit for precise placement. Target: Up to 3 pathologically confirmed metastatic lymph nodes. Timing: Performed before initiation of NST. Rationale: Nitinol markers are radiopaque, MRI-compatible, and resistant to migration. Standard method for tumor localization in breast cancer. Post-Marking Protocol: Identical NST and imaging follow-up as Group 1. Surgical Intervention: TAD with marker localization (palpation/imaging-guided excision) + SLNB. Intraoperative frozen section analysis.

Sponsors

Saint Petersburg State University, Russia
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Women ≥18 years. * Morphologically confirmed breast cancer (T1-3N1M0). * ECOG 0-1. * Indication for neoadjuvant therapy. * Signed informed consent.

Exclusion criteria

* No lymph node regression post-neoadjuvant therapy (persistent N1). * Distant metastasis progression. * Severe comorbidities (NYHA III-IV, COPD GOLD D, Child-Pugh C).

Design outcomes

Primary

MeasureTime frameDescription
Intraoperative detection rate of marked lymph nodes (%)Assessed intraoperatively (day of surgery).The proportion of successfully identified and excised marked lymph nodes during surgery, confirmed by visual (carbon suspension) or imaging/metallic detection (metallic marker)

Secondary

MeasureTime frameDescription
Time from Marking to Surgery (Days)From the date of marking procedure (Day 0) to the date of surgery (up to 12 weeks post-marking)Measures the duration (in days) between the lymph node marking procedure (carbon suspension or metallic seed placement) and the subsequent surgical intervention (targeted axillary dissection). This assesses the clinical feasibility and logistical timeline between marking and definitive treatment
Quality of Life (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Breast Cancer Module [EORTC QLQ-BR23] Scores1. Baseline (pre-marking), 2. Post-neoadjuvant therapy (pre-surgery) 3. 1-month postoperatively.Patient-reported outcomes assessed using the validated 23-item EORTC QLQ-BR23 questionnaire, which measures: Functional scales (Body Image, Sexual Functioning, Sexual Enjoyment, Future Perspective; higher scores = better outcomes), Symptom scales (Systemic Therapy Side Effects, Breast Symptoms, Arm Symptoms, Upset by Hair Loss; higher scores = worse outcomes). All items are scored 1-4 (raw scores) and transformed to a 0-100 scale. For functional scales, 100 represents optimal functioning; for symptom scales, 100 represents maximal symptom burden.

Countries

Russia

Contacts

Primary ContactAlina A Olchonova, Physician
dr.lazakovich@gmail.com+79818197785

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026