Active not recruitingOBSERVATIONAL

The OPBC-07/microNAC Study

This study investigates if it's safe to avoid a major lymph node surgery in breast cancer patients. Many patients with advanced or aggressive early-stage breast cancer receive chemotherapy before surgery. After this treatment, if only very small amounts of cancer (called micrometastases) remain in the armpit lymph nodes, some surgeons are starting to skip a full removal of these nodes. This research looks at past patient data from many hospitals to see how these patients have done. The aim is to help doctors decide the best treatment plan for those with tiny remaining cancer cells in their lymph nodes, ensuring patients receive effective and safe care.

At a glance

Status

Active not recruiting

Sponsor

University Hospital, Basel, Switzerland

Enrolment target

2,000

Start

15 May 2024

Estimated completion

01 Jun 2025

Breast Cancer

What is this study about?

Chemotherapy before surgery, often called 'neoadjuvant chemotherapy', is a common treatment for certain types of breast cancer, especially if it's advanced or aggressive. After this chemotherapy, doctors usually check the lymph nodes in the armpit to see if any cancer cells are still there. If the chemotherapy works very well and clears the nodes, patients can often avoid surgery to remove more lymph nodes. However, if some cancer remains, more extensive surgery is typically done.

Increasingly, doctors are considering skipping this bigger surgery (called axillary lymph node dissection) when only very tiny amounts of cancer, known as 'micrometastases', are left in the lymph nodes after chemotherapy. To make sure this is a safe approach, we need to look at what happens to patients over a longer time. This study is doing just that: it's looking back at the health records of breast cancer patients treated between 2013 and 2024 at over 50 hospitals across the UK.

The main goal is to find out if it is safe to not remove all the armpit lymph nodes if only these tiny traces of cancer remain after chemotherapy. The results will give doctors important information to help them make the best decisions about treatment for their patients, potentially reducing the need for more extensive surgery while keeping patients safe and well.

Key takeaways

The study looks at past records, so there's no direct impact on patients taking part.
It aims to find out if skipping major lymph node surgery is safe for certain breast cancer patients.
This applies to patients who had chemotherapy before surgery and only tiny cancer cells left.
The results will help doctors plan the best treatment for future patients.
All patient data is kept private and anonymous.

Who may be eligible?

This study is looking back at records of adults (men and women aged 18 and over) who were treated for breast cancer that hadn't spread widely (Stage I-III). They would have received chemotherapy before their surgery.

Crucially, these patients would have had only very tiny amounts of cancer cells (micrometastases) remaining in their armpit lymph nodes after their chemotherapy. They also need to have had specific tests to check their lymph nodes and at least one year of follow-up after their treatment. The study will not include patients who had cancer that had spread widely, or who only had very small, isolated cancer cells (not micrometastases), or those with a specific type of breast cancer called inflammatory breast cancer.

Quick self-check

Are you an adult (18 or older) who had breast cancer (Stages I-III)?
Did you receive chemotherapy before your breast cancer surgery?
Were only tiny amounts of cancer (micrometastases) found in your armpit lymph nodes afterwards?
Did you have at least one year of follow-up after your treatment?
Your cancer was not inflammatory breast cancer or widely spread (Stage IV) when diagnosed.

This is a guide only — the research team will confirm whether you can take part.

What does participation involve?

This is a 'retrospective' study, meaning it looks at existing patient records from the past. You will not be asked to do anything new or extra. Your doctor will provide your anonymised medical information and treatment history to the study team. You won't have any extra appointments, tests, or medication as part of this study, and it won't affect your current or future care. The study simply analyses what happened to patients who already received their treatment, with a focus on their progress at least one year after their surgery.

Potential risks and benefits

Because this study looks at existing, anonymised patient records, there are no direct risks or immediate benefits to you from participating. Your medical care will not be changed. However, the information gathered will be extremely valuable. It will help doctors understand the safest and most effective way to treat future patients with similar breast cancer, potentially allowing some to avoid more extensive surgery. This type of research helps improve overall breast cancer care. You have the right to ask your doctor if your data is being used and to withdraw it if you prefer, although it will be anonymised.

Locations (84)

Valleywise Health Medical Center
Phoenix, United States
Cedars-Sinai Medical Center
Los Angeles, United States
University of California
San Francisco, United States
Providence Saint John's Cancer Institute
Santa Monica, United States
University of Miami
Coral Gables, United States
Dana-Farber Cancer Institute
Boston, United States
University of Michigan
Ann Arbor, United States
Mayo Clinic
Rochester, United States
NYU Langone Health
New York, United States
Memorial Sloan Kettering Cancer Center
New York, United States
Montefiore Medical Center
New York, United States
University of Rochester
Rochester, United States

+72 more sites — see the official record for the full list.

Common questions

What are 'micrometastases'?

Micrometastases are very tiny clusters of cancer cells, too small to be seen with the naked eye, that might remain in the lymph nodes after chemotherapy.

What is 'neoadjuvant chemotherapy'?

This is chemotherapy given before surgery to shrink the cancer, making the surgery easier and sometimes more effective.

What's the difference between full lymph node removal and skipping it?

Full lymph node removal (axillary lymph node dissection) means taking out many lymph nodes. Skipping it means only taking out a few specific nodes, potentially leading to fewer side effects.

Will my personal details be shared?

No, all patient information used in the study is anonymised, meaning your personal details are removed so you cannot be identified.

How will this study help patients?

It will provide important information to doctors, helping them make more informed decisions about whether it's safe for certain patients to avoid a full lymph node removal surgery.