Surgery is the standard of care for axillary staging but has recognised problems such as infection, sensory disturbance and arm lymphoedema. Ultrasound technologies now offer the promise of a radiological alternative to surgical staging.
SENTINUS is a multicentre phase II trial to assess the technical feasibility and diagnostic accuracy of intradermal microbubbles and contrast-enhanced ultrasound (CEUS) to identify sentinel lymph node (SLN) metastases in breast cancer patients compared to axillary surgery. The study incorporates a training and mentorship programme for participating imaging specialists.
If the research is successful, the next stage will be to design a RCT to test the non-inferiority of CEUS sentinel lymph node core biopsy compared to axillary surgery in terms of overall survival and locoregional recurrence.
- Technical feasibility - To determine whether 10 experienced imaging specialists in 5 UK Breast Centres can be trained to consistently identify, core biopsy and clip mark axillary SLN in patients with breast cancer.
- Diagnostic accuracy - To determine the overall diagnostic accuracy of a CEUS SLN core biopsy as a test to identify SLN metastases as compared to the reference standard of axillary surgery.
- Patient/ imaging specialist satisfaction – To assess patient and imaging specialist satisfaction with the CEUS SLN procedure.
Inclusion/ Exclusion criteria
Patient Inclusion Criteria
- Histologically confirmed invasive carcinoma of the breast without palpable axillary LN with planned primary surgical treatment.
- Normal grey scale axillary ultrasound or benign biopsy of morphologically abnormal LN.
- Participant is willing and able to give informed consent for participation in the trial.
- Aged 18 years or above.
Patient Exclusion Criteria
- Previous ipsilateral breast cancer treated with radiotherapy or chemotherapy or recurrent breast cancer.
- Female participant who is pregnant, lactating or planning fertility preservation during the course of the trial.
- Allergy to contrast.
- Inflammatory or locally advanced breast cancer
- Metastatic breast cancer
- Inability to raise ipsilateral arm above head.
- Multiple medical co-morbidities (ASA 4 or above)
- Previous ipsilateral axillary surgery.
Planned sample size and timeline
The total number of patients recruited will be 250 from 5 sites.
Every site will put forward 2 imaging specialists for training who will then each perform 25 CEUS SLN core biopsy procedures.
The timeline is 2 years from October 2020 to October 2022.
Please see the ISRCTN website